All rights reserved. First Break or any part thereof may not be reproduced, stored in a retrieval system, or transcribed in any form or by any means, electronically or mechanically, including photocopying and recording, without the prior written permission of the publisher.
PAPER
The publisher’s policy is to use acid-free permanent paper (TCF), to the draft standard ISO/DIS/9706, made from sustainable forests using chlorine-free pulp (Nordic-Swan standard).
The use of gaming and geodata visualisation in preparation for high Arctic research fieldwork
31 The use of gaming and geodata visualisation in preparation for high Arctic research fieldwork
Daniel Kramer, Marius Opsanger Jonassen, Kim Senger, Rafael Kenji Horota and Solveig Solem
Special Topic: Environment, Minerals and Infrastructure
39 Ultra high-resolution shallow marine imaging with a sparker over a deep streamer
Vetle Vinje, Florian Josse, Thibaut Choquer, Peng Zhao, Isabelle Thauvin, Patrick Charron and Philippe Herrmann
47 Timing the triggers: Radiocarbon chronostratigraphy for geohazard assessment in offshore Myanmar
Joy Muraszko, Elena Grimoldi, Riccardo Borella, Andrea Caburlotto and Francesca Zolezzi
53 Global inversion of ERT and IP data using VFSA for improved detection and uncertainty assessment of leachate accumulation in urban landfills
Giorgio De Donno, Michele Cercato and Davide Melegari
59 An exploratory geophysical study focused on a site of a wind energy generation park
Ana Abreu, Nicolás Valverde, Valentina Curutchet, Misael Lemes, Santiago Delgado, Freddy Rondon and Javier Sánchez-Rojas
66 Calendar
cover: Navigational beacon in an Arctic region. This month we feature a study using gaming and geodata visulation in preparation for Arctic fieldwork.
European Association of Geoscientists & Engineers Board 2025-2026
Environment, Minerals & Infrastructure Circle
Andreas Aspmo Pfaffhuber Chair
Florina Tuluca Vice-Chair
Esther Bloem Immediate Past Chair
Micki Allen Liaison EEGS
Martin Brook Liaison Asia Pacific
Ruth Chigbo Liaison Young Professionals Community
Deyan Draganov Technical Programme Representative
Madeline Lee Liaison Women in Geoscience and Engineering Community
Gaud Pouliquen Liaison Industry and Critical Minerals Community
Eduardo Rodrigues Liaison First Break
Mark Vardy Editor-in-Chief Near Surface Geophysics
Jonathan Redfern Editor-in-Chief Petroleum Geoscience
Robert Tugume Member
Anke Wendt Member
Martin Widmaier Technical Programme Officer
Sustainable Energy Circle
Giovanni Sosio Chair
Benjamin Bellwald Vice-Chair
Carla Martín-Clavé Immediate Past Chair
Emer Caslin Liaison Technical Communities
Sebastian Geiger Editor-in-Chief Geoenergy
Maximilian Haas Publications Assistant
Dan Hemingway Technical Programme Representative
Carrie Holloway Liaison Young Professionals Community
Adeline Parent Liaison Education Committee
Longying Xiao Liaison Women in Geoscience and Engineering Community
Martin Widmaier Technical Programme Officer
SUBSCRIPTIONS
First Break is published monthly. It is free to EAGE members. The membership fee of EAGE is € 85.00 a year including First Break, EarthDoc (EAGE’s geoscience database), Learning Geoscience (EAGE’s Education website) and online access to a scientific journal.
Companies can subscribe to First Break via an institutional subscription. Every subscription includes a monthly hard copy and online access to the full First Break archive for the requested number of online users.
Orders for current subscriptions and back issues should be sent to First Break B.V., Journal Subscriptions, Kosterijland 48, 3981 AJ Bunnik, The Netherlands. Tel: +31 (0)88 9955055, E-mail: subscriptions@eage.org, www.firstbreak.org.
First Break is published by First Break B.V., The Netherlands. However, responsibility for the opinions given and the statements made rests with the authors.
Mike Branston Vice-President
Sanjeev Rajput President
Martin Widmaier Technical Programme Officer
Andreas Aspmo Pfaffhuber Chair Environment, Minerals & Infrastructure Circle
Maren Kleemeyer Education Officer
Johannes Wendebourg Chair Oil & Gas Geoscience Circle
Giovanni Sosio Chair Sustainable Energy Circle
Diego Rovetta Membership and Cooperation Officer
Eric Verschuur Publications Officer
Christian Henke Secretary-Treasurer
Maximising energy resources is the theme for next year’s Annual in Aberdeen
Ariel Flores, senior vice president, subsurface, bp, and chair, Local Advisory Committee, sets the scene for 87th EAGE Annual Conference & Exhibition being held in Aberdeen, Scotland on 8-11 June 2026 at the P&J Live Convention Centre.
EAGE’s 2026 theme is Maximizing Recovery: Unlocking Value Through Technology and Partnerships, building on the successful, well attended event held in Toulouse, France. This is especially relevant as the world is in an ‘energy addition’ phase – consuming increasing amounts of both fossil fuels and low carbon energy to meet growing demand. The reality is that oil and gas will be needed for decades to come, with demand continuing to be robust beyond 2035.
Meeting this demand will only be possible by utilising the latest technology and leveraging strategic partnerships to maximise recovery in a cost challenged environment. The geoscience and engi-
neering community has much to contribute by coming together with key partners to address the challenges and opportunities ahead. The conference therefore provides a much-needed platform to explore ideas and build the networks needed for the work ahead.
The programme has been designed to engage, inspire and facilitate collabo ration. There will be representation from industry, academia, IOCs, NOCs and many more experts and thought leaders. It is made up of keynote presentations, technical sessions, workshops, field trips and a major exhibition showcasing the latest industry trends, research and tech nology.
This will be the first time the con ference is held in Aberdeen. Known for decades as a global hub for oil and gas, the city is now also a leading force in energy transition, aiming to become the Net Zero Capital of Europe. Aberdeen brings together deep industry knowledge, cutting-edge research, and a growing eco system of low-carbon innovation. Beyond the conference, delegates can explore a region rich in natural beauty and culture. From striking coastlines and historic castles to world-famous whisky and warm
Scottish hospitality, Aberdeen offers a truly memorable setting for this landmark EAGE gathering.
Finally, I would like to thank everyone who has helped to make this event possible, and I look forward to continuing the conversation with you all in Aberdeen.
Whether you’re a returning attendee or joining EAGE Annual for the first time, EAGE Annual 2026 offers an opportunity to reconnect with colleagues, explore new technology, attend presentations, meet clients, search for career opportunities, or simply stay engaged with the latest in geoscience and engineering. Stay updated on www.eageannual.org.
New Circle is born
Underground hydrogen storage at GET
Kaust team wins Laurie Dake Challenge
Ariel Flores.
Boka Atlantis, an offshore support vessel berthed in the new part of Aberdeen Harbour.
Wide-ranging Strategic Programme planned for GET meeting
A major feature of this year’s EAGE Global Energy Transition (GET) Conference & Exhibition in Rotterdam on 27–31 October 2025, will once again be the Strategic Programme. It is expanding significantly in both size and scope, with an exceptional line-up of high-level speakers across the energy landscape, from policy, regulation, and industry.
These high-level panel discussions bring together industry leaders, academics and analysts to discuss the wider economic and policy issues affecting global energy transition and have played a key role in the increasing popularity of the GET programme. Early confirmed panellists include directors, vice-presidents, and advisers from leading organisations such as the European Commission, Shell, Equinor, EBN, Viridien, Microsoft, and TNO, alongside influential researchers and policy experts from institutions like The Hague Centre for Strategic Studies, NTNU, and TU Delft.
Here’s a quick look at what to expect:
Geopolitical reset: Power, policy, and the global energy future
Tracking the momentum of global decarbonisation initiatives has become increasingly complicated by geopolitical turmoil. With topics ranging from regional policy to global supply and demand scenarios, the panel aims to bring clarity to ongoing climate agreements, the rise of renewables, and how to track real progress in our complex, fast-changing world.
Critical raw materials in Europe
As Europe pushes forward with clean energy goals, securing access to critical raw materials (CRMs) is more important than ever. EU policy, circularity, land and
Not too late
Diederik Samsom to speak on climate issues at Opening Ceremony
An important highlight of the Opening Ceremony on 27 October will be a keynote by Diederik Samsom, former party leader of the Dutch Labour Party and chief of staff to the European Commission’s Commissioner for Climate Action. Drawing on his deep experience in energy, climate policy, and sustainability, Samsom will offer his insights into Europe’s path toward a low-carbon future.
marine exploration, and the innovation networks supporting a sustainable supply of CRMs will be on the agenda.
Can Europe lead the way with a clear roadmap for new energy innovation and competitiveness? Europe has led in areas like CCS and offshore wind, but can it stay ahead? This session addresses competitiveness, the EU Clean Industrial Deal, and how to turn decarbonisation into growth. Expect a timely discussion on strategy, policy, and public-private alignment.
Financing and insurance of the Energy Transition
Transition requires investment, but where will it come from, and how can it be protected? This session digs into funding strategies, insurance frameworks, investor expectations, and the role of geoscience
The call for late-breaking abstracts is open until 15 September. Submissions will be considered for poster presentations only, perfect for showcasing your latest research or field results.
To take part in EAGE GET 2025, register by 1 September to benefit from early bird discounts. Free visitor passes are also available, and those looking to make the most of the event can opt for an all-access pass, which includes entry to workshops, field trips, and short courses. For full programme details and registration information, visit eageget.org.
in derisking large-scale clean energy projects.
Geoscience communication and public engagement in the energy transition: Experiences and lessons Organised by the EAGE Special Interest Community on Geoscience Communication & Public Engagement, this session highlights the critical role of engaging the public in energy transition projects. Featuring insights from geothermal, wind, hydrogen, and subsurface storage initiatives, it will explore real-world case studies and strategies for building trust, addressing concerns, and fostering inclusive participation in sustainable energy development.
Geological risk assessment in energy transition technologies: The importance of modelling tools and techniques
This session explores how geoscience modelling supports key energy transition projects like geothermal, CCS, hydrogen, and offshore wind. We’ll discuss its role in risk assessment, resource estimation, and project planning, as well as its value in improving communication across teams. GET 2025 offers an unmissable opportunity to explore where the energy transition is heading and who is leading the way. Learn more: https://eageget.org/ strategic-plenary-agenda/
LEAP ENTIRE WORKFLOWS IN A SINGLE BOUND
COMPLETELY REPLACING TRADITIONAL WORKFLOWS
DUG Elastic MP-FWI Imaging enables simultaneous inversion of reflectivity (3-component, directional, horizontal), P-wave velocity, S-wave velocity, density, P-impedance, S-impedance, and Vp/Vs ratio, providing quantitative-interpretation-ready outputs of the highest resolution and amplitude fidelity — using field-data input. In this example we can readily identify the reservoir location — a beautiful flat spot!
No more jumping through hoops — DUG Elastic MP-FWI Imaging gives you everything you need with one powerful leap.
Available in DUG Insight!
Prospects of underground hydrogen storage to feature at GET 2025
At GET 2025, Dr Kamaljit Singh, associate professor, Institute of GeoEnergy Engineering, Heriot-Watt University (UK) will be presenting his short course: Underground hydrogen storage in rocks: pore-to-core scale flow processes, X-ray imaging and modelling. Here he tells us what’s involved.
What inspired you to develop the course?
My motivation stems from the urgent need to advance underground hydrogen storage (UHS) as a vital component of hydrogen economy, which will play a key role in addressing climate change and global warming. Large-scale UHS will become essential for balancing supply and demand and ensuring energy security. Because UHS is a relatively new field, there are many outstanding challenges, particularly related to physical and microbiological processes that occur underground at high temperature and pressure conditions, which are not yet fully understood. This course is designed to explore these processes by connecting fundamental concepts with the latest research insights especially using imaging and modelling techniques.
Your course places strong emphasis on 3D and 4D X-ray imaging and pore-scale modelling
3D and 4D X-ray imaging are state-ofthe-art tools for visualising multiphase flow processes in porous systems. In our laboratory, we use these techniques to observe cyclic hydrogen injection in rocks under realistic subsurface pressure and temperature conditions. Pore-scale modelling complements these experiments by allowing us to simulate flow processes and extract critical parameters like capillary pressure and relative permeability, which serve as essential inputs for largescale simulations.
Recognising the diverse backgrounds of participants, we will begin by introducing fundamental concepts of porous media flow, imaging and image processing before progressing to more advanced topics. Participants will be guided through various workflows for image processing specific to UHS. We will also showcase videos of our experimental work conducted in cutting-edge imaging facilities.
Course attendance
What are some of the most surprising or promising findings in your recent research?
Our experiments with cyclic hydrogen injection in porous rocks have revealed complex flow patterns, particularly in heterogeneous rocks.
We also found that different experimental protocols can lead to entirely distinct flow behaviours, underscoring the sensitivity of these processes to initial and boundary conditions. One surprising finding was the extent of hydrogen dissolution in water.
Despite hydrogen’s low solubility, we observed notable dissolution driven by its high diffusivity. Another challenging area involves microbial interactions and biofilm formation, which can significantly influence hydrogen flow in porous rocks. We are currently developing innovative strategies to visualise these interactions to assess their impact. Sharing these insights, along with the advanced imaging and image processing techniques we have applied to UHS, will be one of the key highlights of this course.
You can attend by selecting the course as part of your GET 2025, All Access Pass or by registering for the course individually. Don’t miss the chance to be part of this forwardlooking discussion at the forefront of the energy transition.
Kamaljit Singh.
The course provides a fundamental understanding of the key physical and microbial processes occurring at the pore-to-core scale during UHS in rocks.
Prepare your abstract for EAGE Digital 2026
Abstracts are already being invited for the 6th edition of EAGE Digital scheduled for 9-12 March 2026 in Stavanger, Norway.
The previous edition of the event in Edinburgh proved an outstanding success attracting more professionals than ever
wanting to keep abreast of all the latest developments as the energy resources sector turns increasingly to digital solutions to enhance operational efficiency and sustainability.
For those wanting to be part of this world-leading conference in the
geoscience field, the call for abstracts is now open with a deadline of 1 November 2025 for submissions via www.eagedigital.org.
All submissions will undergo peer review and may be selected for oral or poster presentations.
ASEG and EAGE join forces to bring geophysical knowledge to a wider global audience
We are delighted to announce our new collaboration with the Australian Society of Exploration Geophysicists (ASEG). This partnership marks an exciting development in the global geophysics community. ASEG’s two flagship publications, Exploration Geophysics and Preview Magazine, are now hosted on EAGE’s EarthDoc platform, expanding access, visibility, and impact for geoscientific content worldwide.
This initiative began with a simple conversation — one of those rare, welcome moments of shared vision — where both organisations immediately saw the potential in joining forces. With mutual enthusiasm and a deep commitment to advancing geophysical science, ASEG and EAGE partnered to provide even greater value to researchers, professionals, and students across the globe.
Exploration Geophysics is a peer-reviewed, open access journal published in partnership with the Society of Exploration Geophysics of Japan (SEGJ) and the Korean Society of Earth and Exploration Geophysicists (KSEG). The journal serves as a vital international platform for original research, case studies, and methodological advances in exploration and applied geophysics.
Its editorial panel brings together reviewers from across the globe, drawing on both industry and academic expertise to uphold the highest standards of quality and relevance. The journal covers a broad range of topics including mineral, petroleum, mining, and environmental geophysics, offering insights that address realworld challenges in diverse geological settings.
Published six times per year, Exploration Geophysics regularly features special thematic sections and curated collections from ASEG’s conferences. Its presence on EarthDoc ensures that this valuable content reaches an even wider audience of geoscientists around the world.
Known for its accessible and engaging content, Preview is Australia’s premier magazine dedicated to exploration geophysics. It serves as an essential resource for professionals in mining, energy, environmental industries, government, and geoscientific research.
Also published six times a year in both print and digital formats, Preview features a vibrant mix of industry news, technical updates, thought pieces, book reviews, and insightful case studies. Regular columns include updates from the ASEG Executive, Branch News, upcoming events, and government initiatives — all curated to keep readers connected and informed. With its approachable style and wide-ranging topics, Preview is not only a go-to publication for ASEG members but also a valued resource for institutions and companies worldwide who rely on current developments in applied geoscience.
This partnership represents more than just enhanced distribution. It reflects a shared vision between ASEG and EAGE — one grounded in the belief that open access to knowledge, professional collaboration, and global visibility are essential to the future of geoscience.
We look forward to the many new connections, collaborations, and innovations this partnership will inspire within the geoscience community.
Near Surface Circle reimagined for the transition era
Andreas Pfaffhuber, chair, Environment, Minerals, and Infrastructure Circle in the EAGE Board, introduces a renaming initiative.
Two years ago, EAGE began a strategic transformation to better align with the rapidly evolving challenges faced by the geoscience community and society at large. The introduction of Circles, replacing traditional Divisions, marked a shift toward greater agility, inclusiveness, and inter-disciplinary collaboration. This model has already proven effective in engaging new stakeholders and expanding our collective impact.
As part of this evolution, we are pleased to announce that the Near Surface Geoscience Circle will now continue its mission under a new name - the Environment, Minerals, and Infrastructure Circle (EMI).
The new Circle name signals a renewed focus on today’s key challenges in near-surface geoscience.
The new name reflects more than just a broadened scope, it signals a renewed commitment to addressing some of the most pressing issues of our time. The EMI Circle will serve as a platform for knowledge exchange, innovation, and outreach across areas vital to a growing global population. These include sustainable infrastructure development, mitigation of natural hazards intensified by the climate crisis, and the responsible management of water and soil resources.
In addition, EMI embraces the increasing demand for critical minerals, resilient infrastructure, and efficient geotechnical risk reduction, all of which are central to the energy transition and sustainable technological development. The Circle also addresses challenges related to UXOs (unexploded ordnance), contaminated ground, mining engineering, groundwater characterisation, and even archaeological geoscience.
To maximise impact, EMI will actively reach out to industry stakeholders including those who may not yet be aware of the solutions geoscientists can provide. The intention is to help bridge gaps between scientific innovation and practical application.
EAGE Education Calendar
TRANS-DIMENSIONAL INVERSION: THE EXAMPLE OF GRAVITY DATA IN 3D USING GRAVITY DATA FROM THE BOULIA REGION (QLD, AUSTRALIA) BY JEREMIE GIRAUD
25 AUG –30 OCT GEOLOGICAL CO2 STORAGE BY ANDREAS BUSCH, ERIC MACKAY, FLORIAN DOSTER, MARTIN LANDRO AND PHILIP RINGROSE
By clearly marking the role that geoscience plays in managing and mitigating environmental and societal challenges, EMI aims to raise awareness of the discipline’s value not only among professionals, but the broader public. We hope to elevate the relevance of geoscientists and inspire greater interest in the geo disciplines and STEM fields more broadly.
We invite all members – current and prospective – to engage with EMI, contribute their expertise, and help shape this exciting new chapter in EAGE’s journey.
LECTURER WEBINAR
ONLINE COURSE
MINS + Q&A
SELF-PACED MATERIAL (16 HOURS) AND 7 LIVE WEBINARS OF 1 HR EACH
7 SEP SATELLITE INSAR DATA: MONITORING FROM SPACE BY ALESSANDRO FERRETTI NAPLES, ITALY DURING THE NSG 2025
9-10 SEP SEQUENCE STRATIGRAPHY: CONCEPTS, METHODS, AND WORKFLOWS BY RENE JONK
Andreas Pfaffhuber.
Make sure to sign up for the NSG2025 experience in Italy
This is a reminder that the highly anticipated Near Surface Geoscience Conference and Exhibition 2025 is only a month away – 7-11 September in Naples.
Awaiting participants are five parallel conferences at one venue -the main event Environmental and Engineering Geophysics, plus Mineral Exploration and Mining; Infrastructure Planning, Monitoring and BIM; Geohazards Assessment Risk Mitigation, and UXO and Object Detection. This rich technical programme includes 250+ oral and poster presentations, 50+ technical sessions, 40+ exhibitors and 450+ attendees. Delegates can also join a short course on Satellite InSAR Data: Monitoring from Space and three highly focused workshops on Geophysical Exploration to Volcanological Areas: imaging challenges and public and operational constraints; Geophysical Applications to Archaeology: innovation in acquisition and data modelling: and Airborne Geophysics: advances and perspectives from different platforms. The workshops offer interactive, real-world case studies appropriate at a city with a storied archaeological and volcanic heritage.
The field trips on offer do much to complement the programme. There will be a visit to the Bourbon Tunnel (Galleria Borbonica), one of the most fascinating underground routes in Naples, a masterpiece of civil engineering constructed by King Ferdinand II of Bourbon in 1853. A
second field trip at the Vesuvius volcano and Oplontis provides the possibility to investigate the relationship between the different types of pyroclastic deposits and their effects on Roman buildings.
The third field trip at the Phlegrean Fields, Pozzuoli, will explore the active Campi Flegrei caldera, a 12 km wide volcanic field characterised by an almost circular structure enclosing numerous volcanic edifices including tuff cones, diatremes, tuff rings, and a few lava domes. The fourth field trip involves one of the world’s most iconic archaeological sites: the Roman cities of Pompeii and Herculaneum. The cities were destroyed
and buried by the Vesuvius Plinian eruption of 79 AD. Lastly, a boat excursion field trip, offering a rare opportunity to explore the coastal geology of the Posillipo promontory and the Phlegraean Fields will be available.
Additionally, the Icebreaker reception and Conference Evening social programmes will be held at the historic monumental Santa Maria La Nova church and cloister, adorned with frescoes by renowned Neapolitan painters from 1600. What better way to intermingle with fellow delegates!
Make sure you register today at eagensg.org to secure your spot.
Mediterranean city of Naples.
What went down at Helsinki NSG in 2024.
PARALLEL CONFERENCES UNDER ONE EVENT 5
Giovanni Florio
NSG 2025 Local Advisory Committee Chair
“ NSG 2025 is set to be a vibrant platform for sharing cutting-edge geophysical innovations across academia, industry, and government organisations. This year’s expanded technical programme is particularly exciting, featuring parallel conferences on UXO detection, mineral exploration, infrastructure monitoring, and geohazards. Attendees will benefit from rich networking and learning opportunities—set in a captivating landscape, between Vesuvius and the Phlegrean Fields, where Earth’s processes are vividly on display. I look forward to welcoming you in Naples!”
HIGHLIGHTS
1. OPENING SESSION ON GEOSCIENCE COMMUNICATION
2. DEDICATED SESSION ON THE CRITICAL RAW MATERIALS ACT: FROM THEORY TO PRACTICE
Get the complete NSG experience: the All Access Pass includes
• Opening Session
• Technical Programme
• Exhibition
• Icebreaker Reception
• Special Talks
• Conference Evening
• Workshops
• Short Course
• Field Trips
• Daily Lunch & Coffee Breaks
50+ Oral and Poster Presentations
Technical Sessions
250+ Attendees
40+
450+ Exhibitors
Associated Societies make their mark at the EAGE Annual
We welcomed 24 of our associated societies at the EAGE Annual highlighting the value of these collaborations for our members.
The societies showcased their current and upcoming projects at a dedicated area in the exhibition floor and took part in a networking meeting that facilitated cooperation talks with their peers and the EAGE Board.
Some of our partner societies were also actively involved in the conference programme. The HPC-AI Society, for example, hosted the panel discussion Powering the future: Is AI just buzz or the real deal in energy? at the Digital Transformation Area (DTA). Doug Norton, the society’s president and panel moderator, spoke of some real wins already happening in the energy industry. ‘Digital twins alone are increasing production while lowering risk and cost for facility operation. For GenAI, there is progress being made on seismic foundation models that can take text in and output graphics. For windfarm simulation, AI is being added to speed simulations by up to 4000 times getting to decision on the same day vs. 40 days. Looking ahead, applying AI to cybersecurity and physical AI hold even greater potential’.
At the International Prospecting Centre, representatives from the Nigerian Association of Petroleum Explorationists (NAPE) presented Growth opportunities in the Niger Delta: Bridging the legacy assets with low-carbon frontiers and
participated in the panel discussion How ultra-deepwater is revitalising oil and gas exploration
According to NAPE president Johnbosco Uche, ‘Active participation at the EAGE Annual creates opportunities to build strategic collaborations with international professional bodies, academia and industry leaders. In a rapidly evolving energy landscape, such partnerships are essential for capacity building, knowledge transfer, and the continuous development of geoscience professionals across Africa’.
Among other notable contributions, John Duhault from the Canadian Society of Exploration Geophysicists (CSEG), was the guest speaker in a dedicated
meetup organised as part of the EAGE Mentoring Programme; and Eleonore Dalmais from the French Association of Geothermal Professionals (AFPG), served as a panellist in Geoscience communication for policy a session hosted by the Geoscience Communication and Public Engagement Community, in collaboration with the Sustainable Energy Circle.
This year’s Technical Programme also featured some of the top presentations from the IMAGE 2024 conference organised by SEG, AAPG and SEPM. Topics covered included fault displacement gradients in mechanically layered rock and sparse ocean bottom node seismic interferometry and inversion.
The EAGE Annual provided a valuable opportunity to (re)connect with our associated societies and develop cooperation talks.
Every month we highlight some of the key upcoming conferences, workshops, etc. in the EAGE’s calendar of events. We cover separately our four flagship events – the EAGE Annual, Digitalization, Near Surface Geoscience (NSG), and Global Energy Transition (GET).
7th International Conference on Fault and Top Seals
14-18 September 2025 – Bucharest, Romania
The event once again will bring together leading geoscientists, researchers, and industry professionals to exchange knowledge and advance understanding in fault and top seal processes across various geological settings. Sharing knowledge from different techniques will help to reduce uncertainty and mitigate risk for conventional, emerging and future applications. A key highlight is the one-day field trip to the Carpathian foothills, one of Central Europe’s most hydrocarbon-prolific regions. The excursion offers a rare opportunity to explore world-class reservoir and seal outcrops in a region that has served as a cornerstone of geological research for nearly 150 years.
Regular fee until 18 August 2025
First EAGE Workshop on Geophysical Techniques for Monitoring CO2 Storage
21-22 October 2025 – Toronto, Canada
This inaugural workshop aims to help connect ideas and methods in carbon storage monitoring for the new wave of commercial projects now underway and the next waves that are about to be initiated. On the agenda will be consideration of storage sites, risk types and levels, regulatory environments, and local geophysical capabilities and how they differ between onshore and offshore and between sites in each environment. These will lead to plans and approaches that are practical and efficient.
An interactive session is planned to conclude the event, ensuring all attendees actively participate, debate, discuss, and propose ideas.
Regular fee until 19 September 2025
First EAGE/ AAPG/ SEG Carbon Capture Utilisation and Storage Workshop (CCUS) 21-23 October 2025 – Al Khobar, Saudi Arabia
This collaborative event intends to lay the foundation for a cornerstone event in the CCUS community, not just in the Middle East, but globally.
A key enabler of CCUS is utilisation, one of the conference themes. By creating valuable products and generating cash flow, utilisation allows us to build the infrastructure needed to decarbonise entire industries and nations. The other topic is storage where Middle East geology offers extraordinary opportunities for carbon sequestration.
A distinctive feature of the workshop will be the focus on the carbonate rock formations of the region.
Register at eage.eventsair.com/eageaapgseg-ccus-workshop
8th Asia Pacific Meeting on Near Surface Geoscience & Engineering (NSGE) 12-14 May 2026 – Bandung, Indonesia
With a focus on applied technologies, sustainable practices, and cross-sector insights, the 8th NSGE will address key topics such as environmental geophysics, engineering applications, site characterisation, urban development, and natural hazard mitigation. As the energy transition accelerates, sessions will also explore the role of near-surface methods in supporting geothermal energy, infrastructure resilience, and carbon storage.
Set in the scenic highlands of West Java, Bandung, a city renowned for its academic institutions, innovation spirit, and cultural vibrancy, provides an inspiring backdrop for this technical and professional exchange.
More details to come. Stay tuned on eage.org
KAUST team triumphs in Laurie Dake Challenge 2025
The Laurie Dake Challenge 2025 concluded with a standout performance from the team representing King Abdullah University of Science and Technology (KAUST). The team’s innovative project secured first place in EAGE’s prestigious student competition.
Team members Abdirizak Omar, Mariia Solodiankina, Rayhan Nugroho, Zakaria Alghamdi, and Akshith Suresh impressed judges with their forward-looking research into CO2 storage, focusing on the potential of basalt formations for permanent carbon capture through mineralisation. This approach could play a transformative role in global carbon management strategies thanks to its capacity for long-term, stable storage.
Reflecting on the experience of presenting their findings at the EAGE Annual Conference, Suresh described it as both humbling and exhilarating. ‘It was an
incredible experience,’ he said, ‘not just to present, but also to learn from brilliant minds from all over the world. We were inspired by the level of discussion and the diversity of approaches taken by other teams.’
Participating in the Laurie Dake Challenge offered the KAUST team a rigorous test of both its technical knowledge and collaborative skills. ‘We gained hands-on experience with geoscience workflows,’ according to Suresh. ‘Just as importantly, we learnt how to work effectively under pressure, adapt quickly to new information, and draw on each other’s strengths.’
The team’s journey to the final round was made possible through the support of the EAGE Student Fund, which helped cover travel and accommodation expenses making the whole experience far more accessible.
Looking ahead, Suresh acknowledged the importance of student-focused initiatives like the Laurie Dake Challenge in connecting academic learning with industry practice. His message to future participants was clear: ‘Go for it. It’s intense, but it’s one of the most rewarding experiences you’ll have.’
To help make future opportunities like this possible, consider donating to the EAGE Student Fund. Your support can open doors for students worldwide to gain experience, grow professionally, and shape the future of geoscience.
EAGE Masterclass on Geothermal Energy comes to Paris
EAGE is hosting its next Masterclass on Geothermal Energy on 17-20 November 2025 in Paris offering a comprehensive programme of short courses taught by leading experts in the field. It is designed to provide participants with a deep understanding of the key technical aspects of geothermal energy development.
Three short courses focusing on a different aspects of geothermal energy make up the programme. It opens with a two-day course led by Andrea Moscariello
(University of Geneva) on geothermal energy systems and their role in the energy transition. Covering everything from shallow ground-source heat pumps to high-temperature power generation and heat storage, participants should gain a complete overview of geothermal energy utilisation, as well as exploration and engineering strategies required for successful implementation.
Denis Voskov (TU Delft) will present a one-day course on geothermal reservoir
engineering, exploring the main principles and challenges of geothermal energy production, supported by both lectures and practical exercises. The programme concludes with a course led by Sebastien Soulas (Avalon Sciences) on trends in borehole geophysics offering insights into the integration of vertical seismic profiling (VSP) for reservoir characterisation and field-scale geophysical monitoring in geothermal context.
Beyond technical training, the EAGE Masterclass also supports career development. As an accredited CPD points provider for the European Geologist (EurGeol) title, EAGE awards up to 20 CPD points to participants completing all three courses. Learn from top experts, gain practical skills, and connect with a global network of professionals. Join the full programme via an All Access Pass, or register for individual courses.
KAUST team.
Dive into different technical aspects of geothermal energy through our Masterclass.
CONFERENCE REPORT
Resource discussions heat up in Morocco
Marrakech was the choice for the First EAGE Atlantic Geoscience Resource Exploration and Development Symposium (AGREDS) held on 5-7 May 2025, attended by over 150 participants ranging from IOCs, NOCs, government Institutions, medium-to-smaller and independent oil and gas companies, service companies and academia.
The keynote by Ken McDermott (Shell) set the stage for discussion on tectonic evolution in the Atlantic region. He focused on the new insights of geodynamic models of the opening of the southern Atlantic, highlighting how the tectonic evolution has influenced heat-flow variability, source rock facies deposition in the Lower Cretaceous along the southern margins. He noted the need to recognise the type of margin domain – Transform, Magma Rich or Magma Poor, the concept of Continental Transition Zone (CTZ) rather than Continent Ocean Boundary (COB) – when working in magma-rich or magma-poor domains, and ideas on identifying available ‘play space’ to high-grade exploration fairways.
Subsequent presentations continued exploring this theme while moving northward from the southern margins, through Central Atlantic and Northern Atlantic margins. Geoffroy Mohn discussed the timing and evolution of rifting in the Central Atlantic (the Moroccan and Scotian Atlantic conjugate margins), with models on paleobathymetry of the Scotia Atlantic margin. Jeff Kraus followed up with
a focused look at the Moroccan-Scotian margins looking specifically at variations in magma budget and extensional rates, defining the margin domains in Agadir and Essaouira offshore basins, and showing the implications of this work on accommodation for clastic fairways.
The second keynote by Douglas Paton (TectonKnow) furthered the debate on the value of the conjugate margins. He provided another variation of margin classification, with a compositional component added, placing local play concept fairways into a larger overarching regional context to better understand implications on heat flow modelling and impacts of higher heat flow of ‘leaky transforms’.
The second set of morning talks started with Jon Teasdale (Geognostics) showing some recent work on high resolution plate tectonics modelling from the present day back to the Trias, captivating the audience with his timelapse model spanning 200 my. He showed a detailed look at the opening of the Central Atlantic rift and the implications for timing of the opening of the Tethys and Caribbean gateways. Hala Chebli (ONHYM) presented recent work she had completed at the University of Texas at Austin on the influence of syn-rift structuring on the linked kinematic systems identified in the offshore Essaouira basin of Morocco. Garry Karner (ExxonMobil) discussed evidence for early Jurassic restricted and isolated shallow marine depositional environments in the Central Atlantic and tied his work to Teasdale’s, then adding
an entertaining discussion on SDRs, what they mean, and how they can be used for understanding depositional settings.
The stratigraphy session covered a wide range of topics including the identification of fans and channels based on slope gradient from seismic data; fieldwork observations from the Barrechid sub-basin and the indication of contribution of non-marine waters; salt tectonics applied to a carbonate platform environment and the tectono-sedimentary influence on reservoir distribution. The High Atlas rifting and unidirectional dykes implications on the origin presentation were widely discussed during the Q&A. Integrated pre-salt evaluation of the Kwanza Basin, as mentioned by one speaker, has opened up new questions.
The keynote on technology summarised the key technologies driving higher efficiency in exploration and development operations. They include low frequency sources for seismic acquisition, FWI (Full Waveform Inversion) and multi-parameter FWI in seismic processing, access to high-quality fast-track data and the use of machine learning.
In the exploration panel, we heard about the use of seismic attributes and the potential overuse of AVO and how we must continue to apply geological intelligence to data and information. We were also reminded of the value of reprocessing old seismic data and the multiple exploration opportunities which Morocco offers.
In the hydrocarbon resources and exploration sessions, we learnt how var-
Bringing minds together: Delegates at the First EAGE Atlantic Geoscience Resource Exploration & Development Symposium.
iable the source rocks in the Atlantic can be depending on which segment of the Atlantic they deposit and their age. Many variables play a vital role for the success of the source rock.
During the session on advancements in geoscience technologies we saw brilliant improvements from some of the main service providers. The talks and additional talks by operators highlighted the impact on subsurface evaluations with real case studies from the Atlantic Margin. Specifically, the impressive advancements give interpreters the comfort of more reliable reprocessed data, new visualisation techniques, and AI-enhanced workflows to derisk prospectivity and identify new plays. The outlier of the session was a talk on core scanning which, although
markedly different from the rest, sparked some insightful questions.
Overall, there was great coverage of the Atlantic Margin with a focus on conjugate margins including a large selection of presentations on Morocco both onshore and offshore, its conjugate Nova Scotia, both sides of the Equatorial Margin, southern Atlantic basins offshore Brazil, Uruguay, Namibia and South Africa, the Lower Congo, Guyana and Suriname, Equatorial Guinea and the Kwanza Basin.
Some of the ideas which resonated during the event included the introduction of the term ‘fairy circles’ in reference to hydrogen exploration; the plea to stop using the term COB (except in transform margins); effect of mantle convection cells and considering dynamic topography; Andrew Pepper reminding us that faults are not needed for hydrocarbon migration and pointing out ACMES, specially during the Aptian and the mid Jurassic; the subaerial depositional model for SDRs; salt imaging and its effect on petroleum systems; heat flow models and lessons; seismic reprocessing, fast-track data, FWI, importance of ultra far-angle stacks; deepwater exploration trends, challenges, lessons learnt and future opportunities; effect of MTCs; plus interaction of turbidites and contourites change of slope and stratigraphic trapping.
The knowledge shared during AGREDS 2025 will undoubtedly contribute to better-informed exploration strategies and innovation as we collectively work toward meeting future energy demands.
Chapters brought their stories to Annual in Toulouse
Visiting Local Chapter representatives made the most of the final day of the EAGE Annual Conference, when they met to reflect on some key issues facing the geoscience community and review them through the lens of local engagement.
The discussion was led by Dong Zhang (LC Netherlands) and covered such questions as how Earth scientists can better communicate the role of geoscientists in critical areas such as climate change or raw mineral resources, which of course was one of the central themes debated in Toulouse. For Local Chapters, one of the main difficulties is the sheer breadth of the field. Geoscientists operate across such a wide range of fields. As a result, the public is often not aware of their contribution.
Chapters were universal in their agreement that one essential skill was
required for communication: storytelling. ‘It’s simply no longer enough to be good at what we do at a technical level,’ said Aimie McSeveney (LC Oslo). According to Hayet Serradji (LC Paris), ‘We lead the technical conversation, but we do not share our experiences with the broader public. The challenge is not just to tell our story, but to share our values – especially with students and kids.’
The panel also tackled some specific factors that are driving the closure of geoscience programmes in some regions – the latest example being the phasing out of the Earth Sciences curriculum at the Vrije Universiteit of Amsterdam. While this trend has not reached everywhere equally, there is a concern it may spread and various countries – from France to Azerbaijan – have observed a shift in the nationality of students choosing a study path in geosciences: the EU component is decreasing, with more enrollments going towards renewable energy programmes or data science. ‘This shift reflects changing interests, policy priorities, and funding pressures,’ explained Tiexing Wang (LC London). ‘But the need for geoscientific expertise in the energy transition remains critical. The challenge is making
that value visible and understood before we create a knowledge gap we can’t easily fill.’
The meeting was also a space to trigger new collaborations and share best practice. Haoxing Zhu, representing a prospective new Local Chapter based in northeast China, talked about communicating directly with the public and choosing the right channels to reach it. LC Paris has had positive experiences with its happy hour, a mix of learning and networking, which has been attracting a high number of students. Leyla Alimuradova (LC Azerbaijan) reported on her work bridging different stakeholders through communication, and reaching out to local students with an EAGE Day.
Local Chapter group makes its presence felt.
Discussing Chapter experiences.
Student and community activities flourish at Toulouse Annual
The EAGE Annual 2025 in Toulouse offered an enriching experience for both students and professionals, bringing together more than 300 participants in a dedicated Student Programme and a wide range of activities in the Community Programme.
The Student Programme welcomed 329 students from around the world to take part in a variety of activities designed to support their academic and professional growth. One of the key highlights was the final round of the Laurie Dake Challenge, where teams presented their CO2 mineralisation projects to an expert jury. The team from KAUST (King Abdullah University of Science and Technology) was announced as the winner during the Opening Ceremony. Sponsored by Equinor and the EAGE Student Fund, the challenge showcased the importance of student-led innovation in the energy transition.
Students also had the opportunity to explore Toulouse’s geological heritage during a dedicated field trip, test their knowledge in the EAGE Global GeoQuiz, and participate in the Exhibition Tour & Education Hunt to connect with industry representatives. A standout activity was the opportunity for students to experience a trial job interview. In the end 28 students took part in the mock interviews conducted by professionals from four companies, receiving practical feedback to boost their confidence and career readiness. The student programme concluded with the Networking Café, offering students direct access to potential employers and academic mentors in a relaxed and welcoming environment.
Space for exchange and innovation
Running in parallel, the Community Programme offered a rich platform for engagement at the EAGE Community Hub, located in the heart of the Exhibition Hall. Attendees could meet with Local and Student Chapters, Technical Communities, and Special Interest Groups, and learnt more about EAGE services including EarthDoc, Learning Geoscience, and membership benefits.
Innovation was a key theme this year, highlighted by the EAGE Hackathon entitled EAGE Agents , where participants created AI-driven solutions for seismic data processing. Winning projects were presented at the Digital Transformation Area, drawing attention to the potential of agentic AI in geoscience workflows.
The Community Programme also featured engaging sessions such as Geoscience Narratives, which focused on storytelling as a tool for public engagement, and Geosecrets of France, where local experts revealed the fascinating geology of the Toulouse region. The Local Chapters’ Panel gave active members a platform to share best practices and inspire new initiatives. Meanwhile, the Annual General Meeting for Members (AGMM) offered a forum for dialogue with the EAGE Board. To support personalised networking, the Brain Match activity helped participants connect with like-minded peers and experts from across the globe.
Together, the Student and Community Programmes at the EAGE Annual 2025 reflected the Association’s commitment to education, innovation, and global collaboration, thereby empowering geoscientists to shape the future of the field.
GeoQuiz competition in progress.
Celebrating 10 years of the EAGE Americas Office
In 2015, the EAGE took a major step in expanding its global reach by establishing a dedicated Americas office, headquartered in Bogotá, Colombia. Today, as we mark a decade since its founding, we look back on the growth of a team and a mission that have brought geoscientists and engineers across the region together. It is also a moment to celebrate its achievements including building of a staff 70% made up of women making it a model of inclusive leadership to keep advancing geoscience across borders.
Operations began in 2017, with the First EAGE/AMGP/AMGE Latin-American Seminar on Unconventional Resources in Mexico that welcomed 150 attendees. Just two years later, in 2019, EAGE hosted another successful event in Mexico – the First Workshop on Deepwater Exploration: Foster Collaboration to Unlock Potential –with 200 participants thereby setting the foundation for a growing presence across the Americas. Since then, the office has developed over 11 events per year in countries including Brazil, Guyana, Colombia, Argentina, and Canada.
The team’s close collaboration with key local organisations, e.g., SBGf, CSEG, Geological Society of Trinidad & Tobago, ACGGP, IAPG, and AGEOCOL, has ensured every event is relevant, regionally grounded, and built with purpose.
Edward Wiarda, EAGE past president (2024), recalls his experience with the Americas office: ‘The regional office arrived in Bogotá at about the same time I landed with my young family in Colombia to work for Ecopetrol as a principal
geophysicist. Independently, and with a shared passion and dedication, we all set off to work transferring, sharing and implementing knowledge, technical solutions, hard-learnt lessons, skills and innovations from around the world to Colombian basins and the LATAM region. It was only a matter of time that we would join forces and form a very productive, fun and fruitful collaboration. This soon culminated into many highlights and activities including a rejuvenated Student Lecture Tour through Colombia, Mexico, Brazil and Argentina, and organising many successful ‘firsts’ of EAGE workshops and conferences in the region, with hot industry topics like Advanced seismic solutions and new exploration concepts to unlock the potential of the Caribbean, High performance computing and the Guyana-Suriname Basin.
The EAGE Americas office represents a celebration of gender equality, geographic expansion, and cultural diversity within the EAGE, and cross-border knowledge sharing between key regions. We should be proud of the team’s resilience through Covid times and continuing efforts to push our energy transition mission and the new Sustainable Energy Circle roadmap in the region. Thanks to the office, the EAGE is widely considered as a trailblazer for energy transition and sustainable energy (geothermal, CCS, and critical earth minerals) in the Americas.’
Francois Lafferriere, COO at Eliis, provides this perspective from a commercial point of view. ‘EAGE Americas has played a crucial role in our company’s growth and visibility in the region. Its events have
provided valuable connections and opportunities from the very beginning with a strong focus on key regional energy challenges, excellent technical exchanges, and fantastic networking, helping us grow a vibrant user community across the Americas. We congratulate EAGE Americas on its 10-year anniversary and look forward to continuing our support in the years ahead.’
For the future, the EAGE Americas office remains focused on key technical and regional priorities: seismic acquisition, CO2 monitoring and storage, and deepwater exploration, especially in areas like the Guyana-Suriname Basin, Equatorial Margins, and North and South Atlantic Conjugate Margins. Topics like critical minerals and near-surface geoscience are gaining relevance, and the team is ready to support meaningful conversations around them.
Yohaney Gómez, a local adviser for EAGE, reflects: ‘It is gratifying to see the significant role played by EAGE in the America region, overcoming the challenges of the energy transition and successfully moving in a collaborative environment with local associations and professionals through the knowledge shared across the world supporting the development of the region.’
The EAGE Student Fund supports student activities that help students bridge the gap between university and professional environments. This is only possible with the support from the EAGE community. If you want to support the next generation of geoscientists and engineers, go to donate.eagestudentfund.org or simply scan the QR code. Many thanks for your donation in advance!
Delegates at Rio conference.
Personal Record Interview
Seismic, rugby and active philanthropy all part of this geoscientist’s journey
Pascal Breton’s geoscience credentials, e.g., a globally recognised borehole seismic expert and former EAGE secretary-treasurer, belie his current role managing TotalEnergies’ rugby sponsorship programme, not to mention continuing involvement in the NGO he co-founded 27 years ago in Manila to support homeless city children.
Small village start
I grew up in a small town in the Sarthe region of western France. My father was a truck driver, my mother worked at a factory, and few young people around me pursued higher education. In the early 1980s, I became one of the town’s first engineering graduates. After a two-year DEUG in mathematics and physics in Le Mans, I left to study geosciences engineering at the Institut de Physique du Globe in Strasbourg. I had no background in geoscience at the time but I liked the idea of a profession that would allow me to explore the world.
Oil connection
It wasn’t until I was 22 that I first went on an aeroplane! I had to fly to an oil congress in Paris to represent the school. For my finalyear internship I joined the Elf Aquitaine’s research group in Pau, working on emerging techniques in petroleum geophysics. My National Service proved fortuitous. I found myself serving in Tahiti for 18 months working with the CEA (Commissariat à l’Énergie Atomique). The job involved research on circum-Pacific seismicity and geophysical studies of the Mururoa Atoll, still an active nuclear test site at the time.
Borehole specialist
Back home I joined Elf Aquitaine as a geophysicist in Pau, specialising in borehole seismics, an area the company was eager to expand. Our small team quickly developed a reputation for innovation, both in tool development (often in collaboration with service companies) and in data acquisition and processing workflows. Within a
few years, we had earned recognition as one of the world’s leading teams globally in this field.
Sabbatical volunteer abroad
Part of me still wanted to engage with the wider world. I had begun overseas volunteering during my holidays, eventually taking a 15-month sabbatical to co-found an NGO in the Philippines called ANAKTnk (www.anak-tnk.org). It was created to support street children and families in the slums of Manila. The experience left a profound mark on me, and 27 years later, I’m still deeply involved. Today, the NGO supports more than 2500 beneficiaries daily through the work of 230 local staff members. From France, I continue to serve as president, leading fundraising and strategic development.
Back to work
When I returned to France, Elf Aquitaine had become Total. I resumed my role as a geophysicist, this time leading a team focused on integrating advanced reservoir characterisation techniques – AVO, 4D seismic and more – into dynamic reservoir models. While technically stimulating, I began to feel restless.
A communicator is born
By chance I was offered the opportunity to manage university and school partnerships around the world presenting Total’s upstream business and metiers to students, also building partnerships with academic institutions and identifying new talent. These years were among the most reward-
ing of my career. It inspired me to co-author a book La faim du pétrole and give frequent talks to both students and academics on energy, human development and climate challenges. It also revealed a new passion: communication. I fully transitioned into this new role from external relations to VP E&P communication. I also became more active in professional associations, particularly EAGE, where I served as secretary-treasurer.
Gave rugby a try
My communication role eventually led to a completely different environment: managing sports sponsorship. It began with my involvement in TotalEnergies’ local partnership with Pau’s rugby club in SW France. When the 2023 Rugby World Cup was scheduled for France, I managed to procure the job of managing the company’s major sponsorship, encouraged by our CEO Patrick Pouyanné, a rugby fan. The experience brought home that a sport like rugby, rooted in values of respect, solidarity, and community, can serve as a powerful platform for public engagement. Today, approaching retirement, I manage all the company’s rugby partnerships across France, from youth and amateur clubs to professional and French national teams. Though I never played the game myself, I’ve become one of its most devoted ambassadors.
Philosophy for life
Through it all, I’ve tried to stay grounded by three constants: family, the work of ANAK-Tnk, and a love of building bridges – between people, disciplines, and cultures.
Pascal Breton
CROSSTALK
BY ANDREW M c BARNET
BUSINESS • PEOPLE • TECHNOLOGY
Libya’s bid for international business
Libya’s National Oil Corporation (NOC) and the Ministry of Oil and Gas announced last month that 37 companies, including supermajors, have qualified for the first oil and gas exploration licensing round since 2007.
The bidding round includes 11 onshore and 11 offshore blocks across established high-potential basins such as Sirte, Murzuq, and Ghadames, as well as unexplored acreage in the Mediterranean. An updated production-sharing agreement is being crafted to make international participation more inviting.
This is a remarkable development for a country that has descended into unresolved divisions on occasion spilling over into civil war following the overthrow in 2011 of the notorious, autocratic regime of Col Muammar Gaddafi after 42 years in power.
A member of OPEC, the country ranks tenth in world oil reserves of 48.36 billion barrels (OPEC figures), and is Africa’s most prolific oil producer after Nigeria but, in different circumstances, would be the dominant one. The International Energy Agency reported that in June Libya was producing 1.22 million barrels per day (bpd) compared with Nigeria’s 1.43 million bpd.
Amidst decades of turbulence, the extraordinary fact is that ever since oil was discovered in the 1950s, Libya has managed to maintain more or less uninterrupted output, always with some participation by western oil companies, mainly under the auspices of its quasi-independent National Oil Company (NOC).
Italy pursued colonial ambitions including invasions of Eritrea, Somalia and Ethiopia as well as Libya. In 1911 Italy had declared war on the failing Ottoman Empire and succeeded in sequestering Libya, then made up of the provinces of Tripolitania and Cyrenaica.
Italian occupation met with prolonged resistance especially from the Cyrenaica region orchestrated for 20 years until his capture and execution in 1931 by Omar al-Mukhtar, leader of the Senussi Order. His heroics are captured in the 1981 big budget, box office flop The Lion of the Desert funded by Gadaffi with Anthony Quinn in the title role and Oliver Reed as Rudolfo Graziano, the Italian general who eventually captured al-Mukhtar. The film was banned in Italy and not finally shown until 2009.
Once in power (1922) Mussolini visualised Libya as a ‘fourth shore’ sanctioning a brutal ‘pacification programme’ including concentration camps and the death of thousands (see prize winning Genocide in Libya: Shar, a Hidden Colonial History, 2021, by Ali Abdullatif Ahmida, professor of political science at the University of New England).
‘The marriage between oil and politics has rarely been harmonious.’
The declared aim of the new licensing round is to increase Libya’s output to 2 million barrels per day by 2028. Whether the round will be completed is a moot point. The marriage between oil and politics has rarely been harmonious.
First serious mention of oil arose in a report in 1938 by Ardito Desai, an Italian geographer, mountaineer and global explorer extraordinaire who died at the age of 104 in 2001. At that time Libya was ruled by Benito Mussolini’s Italian fascist government. In the earlier so-called scramble for Africa by the Western powers,
Outbreak of the Second World War caused Libya to become embroiled in the Western Desert campaign battles between the Axis powers (Italy and Germany) and the Allies (mainly British troops) and noted for the famous personal rivalry between Generals Rommel and Montgomery. Not surprisingly the researches of Ardito Desio, director of the Libyan Geological Survey from 1936 to 1940, were consigned to the back-burner. His work had mainly focused on water resources and discovery of potassium salts in the Marada Oasis, but he recommended to AGIP, the Italian state oil company, drilling for oil in the Sirte Basin, but the technology of the day proved inadequate to capitalise (see, Ardito Desio: Italian geoscience legend who led first K2 ascent by Franco di Cesare, Franchino Aristide and Francesco Guidi, First Break Vol 22, Dec 2004, pp 83-89).
After the war, Britain briefly governed Tripolitania and Cyrenaica provinces and the French controlled the adjoining largely
desert Fezzan province. A newly independent United Kingdom of Libya was established in 1951 as an extremely poor, war-ravaged country via a settlement brokered through the United Nations. The three provinces were combined with three separate capitals Tripoli (Tripolitania), Benghazi (Cyrenaica) and Bayda (Fezzan) under King Idris as-Senussi, previously Emir of Cyrenaica and the leader of the Senussi Muslim Sufi order.
King Idris courted unpopularity by abolishing the federal system and the provincial legislative assemblies in 1963 and was always vulnerable for being beholden to western powers. He was eventually deposed by Muammar Gadaffi in 1969 in a coup d’état fuelled by perceived regime corruption, Arab nationalism and in the wake of unrest at the West’s support for Israel in the 1967 Six Day War.
The reign of King Idris, however, had been distinctive in bearing witness to the discovery of oil and the establishment of a framework to develop the new found resources. Libya’s prospects were transformed, joining OPEC as the second-largest oil producer behind Saudi Arabia with production peaking at some 3 million barrels per day in 1970, and the economy booming.
With investment from the oil industry already dwindling and confronted with severe loss of revenue from reduced oil production, Gadaffi turned Libya into a pariah state with his well-documented support for anti-Western terrorist organisations worldwide.
This was highlighted by Libya’s apparent involvement in the 1986 bombing of a Berlin nightclub in which two American soldiers were killed prompting retaliatory US air attacks on Tripoli and Benghazi, killing 35 Libyans, including Gaddafi’s adopted daughter. The 1988 bombing of the Pan Am flight over Lockerbie in Scotland was the most notorious atrocity involving Libya.
‘Everything changed when Gadaffi emerged as de facto leader’
Yet Libya was allowed back into the international community after Gadaffi admitted responsibility for Lockerbie, paid compensation to families of victims, and also renounced his weapons of mass destruction programme. In September 2004 President George W. Bush formally ended a longstanding embargo ordered by President Reagan on US company operations in Libya. This led to a revival of Libya’s oil fortunes with badly needed investment.
The finding of oil in neighbouring Algeria in 1953 had proved to be a powerful call to action. Legislation in the mid 1950s provided the fiscal terms and conditions for prospecting by international companies, 14 in the original round of concessions, notably Esso (as it was then) and the Oasis group (renamed Waha Oil Company) made up of Continental (ConocoPhillips), Amerada (Hess) and Marathon Oil, but Europen companies were also in the mix. Esso was to be the developer of the first oil from Zelten (now Nasser) field in the prolific east Libyan Sirte Basin (estimated reserves at the time of 2.5 billion barrels), discovered in 1956 with production beginning in 1961. By the end of the decade Libyan output with pipelines to terminals on the coast had risen spectacularly, focused on the Sirte, Ghadamis, Muruzq and Tripolitania basins (with accumulations in Paleozoic, Mesozoic and Tertiary strata). By 1969 14 major fields had been discovered with Libyan exports profiting from the quality of the crude and access to Western European markets with no Suez Canal to contend with.
Everything changed when the 27-year-old military officer Gadaffi emerged as de facto leader in a bloodless coup while King Idris was seeking medical treament in Turkey. Reflecting a trend across Middle Eastern countries culminating in the 1973 oil crisis, Gadaffi immediatedly began the process of nationalising the petroleum industry, establishing the Libya National Oil Company in 1970 and squeezing more revenue from international oil companies. The initial result was more money for Libya to be invested in education, healthcare, and infrastructure. Living standards for many Libyans were improved as part of Gadaffi’s vision for his country based loosely on his philosophising in the The Green Book, which rejected both capitalism and communism. Prosperity at home came at the price of brutal crushing of opposition and all the predictable corruption and nepotism associated with dictatorial rule.
Normalisation was short-lived. Ever since Gadaffi was finally overthrown during the Arab Spring protest movements in 2011, Libya’s rival factions have been unable to come to terms. Oil output has been disrupted repeatedly in the chaotic decade including civil war in 2014. The country remains divided between two rival authorities.The Government of National Stability (GNS) in Benghazi established by the Sirte-based House of Representatives (HoR), is predominantly backed by Egypt, Russia and the United Arab Emirates (UAE). It holds sway over the eastern and southwestern regions, and is aligned with the self-styled Libyan National Army led by Field Marshal Khalifa Haftar, who exercises control over the majority of the country’s oilfields.
Meanwhile, the Government of National Unity (GNU) under Prime Minister Abdul Hamid Dbeibah, predominantly supported by Turkey and Western nations, and endorsed by the UN, exercises control over the capital, Tripoli, and surrounds.
In August last year, Libya lost more than half of its oil production, about 700,000 bpd with some exports during a stand-off between rival political factions over the central bank.
There are some good omens for the successful conclusion of the intended licensing round. Over the past 18 months, key players such as ENI, bp, OMV and Repsol have lifted force majeure and resumed upstream activities. But violence lurks, for example, in May deadly clashes in Tripoli followed the killing of powerful militia leader Abdelghani al-Kikli, also known as Gheniwa.
Finally Libya is not averse to pursing oil ambitions overseas. Greece recently invited Libya to start talks on a controversial, probably unlawful, deal signed in 2019 between the Libyan government (now endorsed by all factions) and Turkey. This would recognise Turkey’s claim to an Exclusive Economic Zone (EEZ) over a wide-swathe of the Eastern Mediterranean. With implications for Cyprus and Egypt, this is a potential regional hotspot the world could do without.
Views expressed in Crosstalk are solely those of the author, who can be contacted at andrew@andrewmcbarnet.com.
JOIN US IN ABERDEEN
The world is in an ‘ energy addition ’ phase. Oil and gas will be needed for decades to come, with demand continuing to be robust beyond 2035. Meeting this demand will only be possible by utilising the latest technology and leveraging strategic partnerships . The geoscience and engineering community has much to contribute.
PXGEO appoints strategy chief
UK’s recoverable oil and gas resources are in danger of plummetting, says Westwood
Westwood has downgraded its estimate of how much oil and gas can be recovered from the UK North Sea to 0.6 billion boe by 2030 and 3.8 billion in the longer term.
In 2019, the UK’s North Sea Transition Authority (NSTA) projected that 1.3 billion boe could be recovered from the UK North Sea by 2030 and 6.5 billion boe between 2025 and 2050
Westwood notes that, according to the UK government’s Climate Change Committee, demand for oil and gas in the UK will be 15 billion boe oil and gas in a ‘balanced pathway’ to Net Zero by 2050. ‘The UK is set to import the majority of this,’ says Westwood.
‘The geology has not changed. Opportunities which existed in 2019 still exist today. Commodity price volatility has always been a challenge. Instead, the fiscal, regulatory and political environment has led to companies deferring or cancelling plans for both short and long-term investments,’ says Westood. ‘There is still a substantial prize available to companies and the government, if the investment environment allows it.’
Westwood estimates that in a high case, the UK Continental Shelf (UKCS) could produce 4.3 billion boe. However, in a substantially improved market environment, including significant changes to tax, licensing and regulatory approvals, and favourable commodity prices, the UK could unlock up to 7.5 billion boe.
‘A major shift in investor sentiment would also be required to achieve this, built on a stable and globally competitive fiscal policy; a supportive investment environment; long-term commitment to ongoing licensing; faster approvals process for new developments and licence awards,’ Westwood states.
If investor sentiment were to deteriorate further, there is a risk that recovery could be as low as 2.6 billion boe.
Of the 7.5 billion boe identified, around 0.5 billion boe is found in near-term developments – opportunities where technical and commercial plans for development are well advanced. An additional 1.4 billion boe is associated with discoveries that Westwood deems to be potentially commercial for development.
Westwood also identifies 20 ‘drill-ready’ exploration and appraisal (E&A) opportunities. ‘In many cases, operators are only waiting for the right investment environment to commit to drilling them. In recent years, while E&A drilling numbers have reached record lows, success rates have been high. With a focus on the potential for future gas developments, there are tangible E&A opportunities particularly in the Southern North Sea, West of Shetland and Quad 9 of the Northern North Sea.’
Of the 7.5 billion boe potential, around 7.3 billion boe is located within 50 km of existing hubs, which would enable
Equinor publishes Johan Svedrup plan
Shearwater wins contract for offshore West Africa survey
Potential upside of the UKCS in the ‘no constraints’ scenario.
Source: Westwood Atlas.
tiebacks to existing infrastructure and thereby reduce development costs, lower emissions intensity and enable development of resources that would otherwise be uneconomic. However, Westwood notes that a high number of fields and hubs could cease production before 2030. ‘Once these facilities cease, it will be too late to unlock many tie-back opportunities and therefore the time for an investment re-set is now.’
The government has stated its intention to ‘not award new licences to explore new fields’. However, substantial volumes of contingent and prospective resources exist in unlicensed acreage. The Westwood Atlas database identifies 9.7 billion boe of risked prospective resources lying within 50 km of a producing hub, with 76% of this currently unlicensed. In addition, 2.3 billion boe of discovered contingent resources lie unlicensed within 50 km of a production hub. ‘Allowing appro-
priate new licence awards provides an opportunity to examine and potentially develop some of this resource. Preventing new licence awards would further damage investor sentiment and send a political message that the UK is a closed shop to global investors.
‘A constructive outcome from the recent government consultations on the Future of the North Sea and the fiscal regime, combined with pragmatic policy change, could unlock significant value. This would boost tax revenues, protect jobs, support lower emissions intensity production and help to fund the energy transition,’ says Westwood.
‘The geology is unchanged. The skills remain, for now. With timely decisions, the North Sea can continue to contribute meaningfully to the UK’s energy system as it transitions to net zero.’
Viridien, TGS and Axxis image OBN North Sea data
Viridien, TGS and Axxis Multi-client have completed the final imaging of OMEGA Merge, to deliver a single dataset across the Heimdal Terrace, Utsira, and Sleipner based on ocean bottom node (OBN) multi-client surveys in the North Sea.
Spanning a total area of 3700 km² from the deployment of more than 250,000 nodes and 9.5 million shots, OMEGA Merge is the largest continuous OBN dataset on the Norwegian Continental Shelf.
Viridien conducted pre-migration matching to ensure consistency in time, phase, amplitude, and frequency content. The velocity model was then unified using Viridien’s time-lag full-waveform inversion (TL-FWI) and long-wavelength tomography technology. Utilising this
unified model, the data was pre-stack depth-migrated to produce a seamless and continuous volume that covers the entire OMEGA Merge area.
Viridien said that the final dataset brings substantial improvements in resolution and structural clarity, revealing previously unseen exploration targets and providing greater confidence in prospect understanding compared to vintage seismic data.
Dechun Lin, EVP, Earth Data, Viridien, said: ‘The final dataset shows unparalleled imaging clarity, offering new insight into complex subsurface structures. This level of detail will support confident exploration and development decisions for years to come.’
Shearwater wins 4D survey in the Norwegian Sea
Shearwater Geoservices has been contracted by Equinor to perform a 4D towed-streamer seismic survey over the Tyrihans field in the Norwegian Sea. It is the first project awarded under the 2021 Equinor framework agreement following a recent extension for an additional two years.
The one-month survey is set to launch in early August. Shearwater will deploy the vessel Amazon Conqueror using Isometrix technology. The survey follows previous 4D campaigns for Equinor, most recently at the Mariner and Heidrun fields in 2024. Applying the same technology to capture repeat high-quality seismic data over the Tyrihans area will enable Shearwater to understand changes to the reservoir over time in the producing field and support future production strategies to optimise output, the company said.
‘The award reflects Shearwater’s strong technical capabilities and consistent operational reliability. Finding good solutions together with our clients is always a priority for us. In this case, we can provide our client with updated reservoir data to support long-term production optimisation and value creation,’ said Irene Waage Basili, CEO of Shearwater.
Meanwhile, Shearwater has implemented measures to increase balance sheet resilience in response to the combination of short-term low activity levels and working-capital intensive projects during the second and into the third quarter of 2025.
The company has agreed a deferral of two debt instalments until January 2027. It has also implemented a cost reduction programme. These and other measures are expected to improve Shearwater’s liquidity over the next 12 months by over $60 million.
Omega OBN Merge brings a unified dataset, providing substantial improvements in resolution and structural clarity.
TGS and Equinor work on CCS digitalization
TGS has announced a collaboration agreement with Equinor to advance the digitalization of carbon capture and storage operations.
Equinor’s Northern Lights project will integrate TGS’ Prediktor Data Gateway into its digital system to enhance management of the full CO2 value chain, from the receiving terminal to permanent storage. By delivering real-time data, the software enables more efficient operations and informed decision-making across the entire CCS process, said TGS. Its functionality supports critical areas such as simulation, capacity planning, CO2
tracking, emissions and financial reporting, permitting, compliance, trading, audits, and health and safety. This will allow Northern Lights to streamline workflows, reduce risk, and ensure regulatory alignment – ultimately creating greater transparency.
‘By leveraging real-time Operational Technology (OT) data through the Open Platform Communications Unified Architecture (OPC UA) information model, Prediktor Data Gateway empowers Equinor with enhanced control and scalability to meet evolving needs,’ said TGS.
Viridien launches industry-first drop node solution
Viridien has launched Sercel Accel, the land seismic industry’s first onshore drop node solution.
‘Accel is designed to overcome the challenges of today’s complex, high-density seismic operations by accelerating survey deployment, increasing operational efficiency gains and consistently delivering the highest-quality data,’ said Viridien.
Accel eliminates the need for nodes to be buried or planted in the field, thereby reducing deployment time and labour requirements, said Viridien. With its droppable design, compact size, and integrated smart portable deployment system, Accel streamlines logistics, improves in-field agility and helps to reduce operational costs by up to 30% and significantly lower HSE risk, the company added.
Accel is powered by the Sercel QuietSeis MEMS sensor. Built-in, field-proven Sercel Pathfinder QC technology also provides near real-time quality control status monitoring and ensures reliable node retrieval.
Accel is said to bring a new level of flexibility to land seismic data acquisition with the introduction of modular Accel Solution Packs which combine nodes, software and services. These are designed to meet wide-ranging survey needs, from initial exploration to large-scale mega-crews. With this approach, customers can tailor and scale their required Accel Solution Packs based on project duration, complexity and strategic goals, bringing unmatched agility to their field operations.
Jerome Denigot, head of sensing and monitoring, Viridien, said: ‘With the launch of Accel, we revolutionised how data is captured, managed, and ultimately trusted by our customers for its total integrity and accuracy. Thanks to its seamless integration with our other acquisition systems, our Accel drop node solution enhances both crew productivity and safety. Scalable and supported by our flexible Accel Solution Packs, including software and services, it heralds the start of a new era in fast, high-resolution land seismic acquisition – accelerating projects of any size.’
bp has appointed Simon Henry as a non-executive director. In 35 years with Shell, he held senior finance and management roles and was chief financial officer and a member of the board from 2009 until 2017. Henry is currently a non-executive director of Rio Tinto. He will also step down as a director of Habour Energy. bp also announced that Pamela Daley, non-executive director, has stepped down from the bp board for personal reasons.
EMGS had one vessel on charter in the second quarter. Atlantic Guardian. It completed the second of two proprietary surveys in India and transited back to Norway for three fully prefunded multi-client surveys in the North Sea with a total contract value of $2.7 million. EMGS recorded three vessel months in the second quarter and expects to record approx. $200,000 in multi-client late sales.
Hess is relinquishing Block 59 offshore Suriname. The block will return to Staatsolie and become part of the open acreage. Block 59 covers 11,480 km2 in water depths of 2700 to 3500 m. After 6000 km of 2D seismic data and 9000 km2 of 3D seismic data were collected in the block, the two previously exiting partners considered the risk too high for drilling an exploration well.
TotalEnergies has signed an agreement to acquire the 25% interest held by Moeve (formerly known as CEPSA) in Block 53, offshore Suriname, joining APA (45%, operator) and Petronas (30%) as partner in the licence. Block 53 contains the Baja-1 discovery.
TotalEnergies has acquired Petronas’ interests in multiple blocks offshore Malaysia and in one block offshore Indonesia. It has also acquired a 25% interest from Chevron in 40 Outer Continental Shelf (OCS) federal leases, including 13 blocks in the Walker Ridge area, nine blocks in the Mississippi Canyon area and 18 blocks in the East Breaks area.
ENERGY TRANSITION BRIEFS
TotalEnergies has acquired a 50% stake in the solar, wind and battery energy storage systems (BESS) portfolio of AES Dominicana Renewables Energy. The deal follows TotalEnergies’ 2024 acquisition of a 30% share in AES solar and battery assets currently under construction in Puerto Rico. The combined portfolio now exceeds 1.5 GW of renewable energy and BESS capacity across the Caribbean.
One of the UK’s most ambitious hydrogen infrastructure programmes has won £96 million public funding for its next phase of engineering, planning and public consultation. East Coast Hydrogen, a partnership of National Gas, Caden and Northern Gas Networks will repurpose and build gas pipelines to deliver clean hydrogen across the North East, the Humber region, Yorkshire and the East Midlands. East Coast Hydrogen will enable power generation and heavy industry across the East Coast to transition from natural gas.
Fugro is working with geographical information system (GIS) software provider Esri to provide integrated geospatial solutions that empower climate resilience decision-making and sustainable development. The initiative will focus on tackling the environmental challenges of Small Island Developing States (SIDS), starting in the Caribbean.
Baker Hughes and Petronas have signed a deal to explore business initiatives that have the potential to support the delivery of Asia’s energy transition. The two companies will enhance local supply chain capabilities and explore the feasibility of implementing a variety of technology solutions including enhanced LNG services and cross-border talent training and development programs to strengthen local field operations.
bp has agreed to sell its US onshore wind business, bp Wind Energy, to LS Power. The business has interests in 10 operating onshore wind energy assets across seven US states, operating nine of them. The assets have a combined gross generating capacity of 1.7 GW (1.3 GW net to bp).
PXGEO appoints Hans-Peter Burlid to steer growth and strategy
PXGEO has appointed Hans-Peter Burlid to the newly created position of chief strategy and transformation officer (CS&TO). Burlid, who is currently the organisation’s CCO, will drive long-term strategic direction to deliver sustainable growth and lasting competitive advantage.
A specialist in seismic data acquisition and marine geophysical services, PXGEO was established in 2021. The firm employs 400 people at its Dubai headquarters and offices in Paris, Houston, and Oslo, along with a dedicated offshore workforce.
‘Having been with PXGEO since its inception, Burlid brings an extensive and deep understanding of the company’s operations, culture and commercial landscape. Known for his strong business acumen and a proven track record of driving complex, cross-functional projects, he is well-positioned to lead the company’s strategic agenda under the guidance of newly appointed executive chairman and CEO Charles ‘Chuck’ Davison Jr,’ said PXGEO.
Burlid has 21 years’ experience largely in finance and commercial roles throughout the maritime and subsea data acquisition industry. Prior to PXGEO, he
Hans-Peter Burlid (Credit: PXGEO).
spent 13 years at the company’s predecessor Polarcus, a publicly traded geophysical service provider, where he rose through the ranks to become CFO for five years.
Davison said:
‘I’ve been fortunate to benefit from Hans-Peter’s commercial expertise and leadership during his tenure as CCO. His deep knowledge of our organisation and his strategic mindset will be invaluable as we advance our growth agenda and execute our longterm plans. With Hans-Peter undertaking this new assignment, we are confident PXGEO will continue to evolve and strengthen its market position around the world.’
PXGEO has begun a search for a new CCO who will take on unified leadership across sales, commercial, and business development functions. Until the new appointment is made, Burlid will continue to serve as CCO.
TGS has won a contract for offshore wind site characterisation, including acquisition, imaging and interpretation services offshore Norway. Ramform Vanguard was due to start acquisition in early July, with a duration of approx. 25 days. The imaging and interpretation work will commence concurrently with data acquisition and final data delivery to the client is expected in Q1 2026.
The Ramform Vanguard is equipped with TGS’s proprietary Ultra-High-Resolution 3D (UHR3D) streamers and integrated geophysical sensors. This technology is designed to sample the seismic
wavefield at a high spatial and temporal rate, providing high-resolution data of the shallow subsurface targets for wind farm development.
Kristian Johansen, CEO of TGS, said ‘Another offshore wind site characterisation contract in Northern Europe extends our acquisition campaign in the region by nearly a month. We are seeing strong client adoption for our high-quality geophysical approach to mapping shallower subsurface targets, which supports data-driven decision making for offshore wind farm development and offers a compelling alternative to traditional geophysical wind solutions.’
Halliburton supplies subsurface modelling for Petronas Carigali
Halliburton has announced a strategic collaboration with Petronas Carigali to advance subsurface modelling and reservoir management. Petronas Carigali will deploy Halliburton Landmark’s DecisionSpace 365 Geosciences Suite and Unified Ensemble Modelling solutions to unify exploration and development workflows and accelerate time to first oil.
‘Halliburton Landmark’s scalable earth modelling and ensemble workflows are a significant evolution from traditional grid-based modelling and deterministic reservoir forecasting,’ said Halliburton in a statement. ‘These technologies are intended to enable Petronas Carigali exploration and asset teams to collaborate in real time using a unified live earth model, with the aim of achieving more accurate reserve estimations through ensemble modelling.’
The Geosciences Suite’s scalable earth modelling maintains geological fidelity across all scales – from basin-wide views to individual fields – to ensure consistent data and models flow from exploration to development. The workflow supports
faster project maturation through the front-end loading process, according to Halliburton. Using the Unified Ensemble Modelling solution, asset teams can automate the generation of multiple probabilistic geological scenarios while integrating real-time reservoir flow data, the company added. This approach is designed to enhance forecast precision, accelerate scenario analysis, and improve confidence in decision making.
‘A harmonised, AI-assisted workflow anchored on a single live-earth model across the exploration and development phases is central to our strategy in achieving our ambitious project delivery targets,’ said Hazli Sham Kassim, senior vice-president of Malaysia Asset and CEO of Petronas Carigali.
The collaboration follows a comprehensive benchmarking of Petronas’ greenfield and mature reservoir practices. The new approach will incorporate multi-scenario probabilistic modelling, supported by AI and machine learning to drive greater efficiency and insight.
Shearwater wins 3D seismic survey off the coast of West Africa
Shearwater Geoservices has won a 3D marine seismic acquisition contract from TotalEnergies on the STP-02 Block off
the West African island of Sao Tome & Principe.
The two-month survey will start early in the third quarter of 2025 using the vessel SW Empress. TotalEnergies has operated the offshore exploration block STP02 since 2024 on behalf of its partners, ANP-STP and Sonangol.
Shearwater CEO Irene Waage Basili said: ‘This award marks the initiation of our extended collaboration with TotalEnergies, as it will be the first project after the recently announced seismic capacity agreement, which is an important strategic platform for both companies, providing Shearwater with long-term visibility on future demand, while also supporting TotalEnergies’ global exploration strategy.
Ukraine’s largest energy company Nattogaz and Baker Hughes have signed a deal to explore opportunities to strengthen and modernise Ukraine’s energy sector.
Through the agreement, the companies will explore technical, operational, and commercial opportunities in key energy sectors, including oil and gas extraction, transportation, storage and processing, as well as geothermal projects, carbon capture technologies, and electricity generation.
Gabon
‘Naftogaz Group is building collaboration frameworks that help Ukraine to overcome wartime challenges, implement modern energy solutions, and strengthen energy independence,’ said Sergii Koretskyi, chief executive officer of Naftogaz.
Key areas of co-operation outlined in the agreement include services and equipment for drilling and well construction; emission reduction solutions, carbon capture projects, hydrogen and
geothermal energy; digital services, automation and analytics; equipment for subsurface operations and production processes; and software for asset management and drilling optimisation.
A separate agreement was signed between Baker Hughes and JSC ‘Ukrtransgaz’, a member of Naftogaz Group, to leverage Baker Hughes’ gas technology equipment portfolio for projects in Ukraine involving underground gas storage and power generation.
launches fiscal regime to attract deepwater investment
Gabon has launched a campaign to attract investment in deepwater oil and gas exploration. With 72% of the country’s deepwater acreage unexplored, the country’s energy ministry is revising existing petroleum laws.
With more than two billion barrels of proven oil reserves and significant gas potential, Gabon has set a goal of holding production above 220,000 barrels per day (bpd) for the short to mid-term.
In 2019, the country introduced its Hydrocarbons Code, amending production sharing contracts (PSC), state profitability and tax. Further revisions of the code are expected to encourage deepwater exploration, said Gabon’s oil and gas ministry.
Major players are already active in Gabon, it added. BW Energy, for example, signed PSCs for exploration blocks Niosi Marin and Guduma Marin in 2024, covering an eight-year exploration period with a two-year extension option. BW Energy and its part ner VAALCO Energy have committed to drilling one well as well as carrying out a 3D seismic acquisition campaign.
BW Energy also has stakes in the Dussafu licence, which features 14 producing wells tied back to a FPSO through a 20 km pipeline. Partners on the licence include the state-owned Gabon Oil Company (GOC) and Panoro Energy. Inde pendent oil and gas company Perenco spudded the Hylia South West discovery in Gabon in early 2024, revealing substantial oil-bearing columns in the Ntchengue Ocean reservoir.
China’s CNOOC launched wildcat drilling on Blocks BC-9 and BCD10 in early 2023 on the back of 1.4 billion barrels of recoverable resource potential, with future discoveries set to
double Gabonese oil production while derisking deepwater exploration.
Meanwhile, Perenco is developing the Cap Lopez LNG terminal in Gabon, targeting first production by 2026. Situated at the existing Cap Lopez oil terminal, the project will introduce a FLNG vessel to monetise offshore gas reserves and reduce flaring. The FLNG vessel will feature a production capacity of 700,000 tons of LNG and 25,000 tons of LPG, supported by a storage capacity of 137,000 m3. The project complements the Batanga LPG facility, which came online in December 2023 with a target production capacity of 15,000 tons of LPG annually. Beyond LNG and LPG, Gabon is planning to expand its sole operating refinery – SOGARA – from 1.2 million tons to 1.5 million tons of crude. This expansion would enable the country to achieve self-sufficiency in refined
Minister of oil and gas Sosthène Nguema has also prioritised increasing storage capacity for refined products in the country from 60 days to 90
‘Deepwater exploration and production stands to transform Gabon’s economy, with potential discoveries supporting the development of a new petroleum hub in Central Africa. Through its aggressive investment campaign, commitment to regulatory reform and engagement with IOCs, the Ministry of Petroleum is strengthening the competitiveness of doing business in Verner Ayukegba, senior vice-president at the African Economic Conference.
Minister of oil and gas Sosthène Nguem.
Equinor reveals plans for Johan Svedrup phase 3
Equinor and its partners are investing $1.3 billion in the third phase of Johan Sverdrup. New subsea infrastructure will increase recovery by 40-50 million barrels of oil equivalent (boe).
‘By building on the technologies, solutions, and infrastructure from phases 1 and 2 of Johan Sverdrup, we can carry out an efficient development with a rapid start-up of production. The project increases the recovery rate and value creation from Johan Sverdrup, one of the world’s most carbon-efficient oil and gas fields,’ said Trond Bokn, senior vice-president for project development in Equinor.
The development includes two new subsea templates which will be tied into existing infrastructure via new pipelines. The investment will increase recoverable volumes from the field by 40-50 million boe, with production expected to start in the fourth quarter of 2027.
To ensure optimal resource utilisation, the project leveraged artificial intelligence to analyse field layouts and well paths. This technology has enabled faster decision-making and resulted in cost savings of $13 million for the phase 3 project, said Equinor.
The expected recovery rate from Johan Sverdrup is already 66%. ‘The phase 3 project is an important step towards achieving our ambition of 75%,’ said Equinor. The average for the Norwegian Continental Shelf (NCS) is 47%, it added.
‘In 2024, Johan Sverdrup set a production record with 260 million barrels of oil, the highest annual oil production ever from a Norwegian field. Every third barrel of oil from the Norwegian Continental Shelf now comes from the field. Phase 3 is an important contribution to maintaining high production from
Johan Sverdrup in the years to come,’ said Marianne Bjelland, vice-president for Johan Sverdrup.
Johan Sverdrup is located in the Utsira High area of the North Sea, 160 km west of Stavanger, in water depths of 110-120 m, covering an area of 200 km2. Production capacity is 755,000 barrels a day, approximately one-third of Norway’s total oil production at current levels.
Phase 3 development comprises two new subsea templates in the Kvitsøy and Avaldsnes areas totalling eight wells (seven oil production wells and one water injection well), tied back to existing templates and pipelines to the P2 platform for processing and export.
Equinor is the operator of the field with 42.6%, along with Aker BP (31.5%), Petoro (17%) and TotalEnergies (8.4%).
US unveils plans for oil and gas lease sale in Gulf of America
The US Bureau of Ocean Energy Management has published a Proposed Notice of Sale (PNOS) for an oil and gas lease sale in the Gulf of America.
Lease Sale 262 will offer approx. 15,000 unleased blocks located 3 to 231 miles offshore across the Gulf’s Western, Central, and Eastern Planning Areas. Covering roughly 80 million acres, the blocks to be auctioned are situated in water depths ranging from 3 m to more than 3400 m.
It is the first of three planned lease sales in the Gulf of America under the 2024–2029 Outer Continental Shelf Oil and Gas Leasing Program. BOEM is also developing a National Outer Continental Shelf Oil and Gas Leasing Program that will include additional leasing opportunities.
‘Offshore oil and gas play a vital role in our nation’s energy portfolio, with the Gulf of America supplying 14% of domestically produced oil,’ said BOEM’s principal deputy director Matt Giacona.
The Gulf of America Outer Continental Shelf spans approximately 160 million acres and is estimated to contain around 48 billion barrels of undiscovered, recoverable oil and 141 trillion cubic feet of natural gas.
Leases awarded through Lease Sale 262 will be for oil and gas exploration and development only. Certain areas may be excluded from this lease sale, including blocks subject to the 8 September 2020, presidential withdrawal, blocks adjacent to or beyond the Exclusive Economic Zone in the northern portion of the Eastern Gap, and blocks
within the current boundaries of the Flower Garden Banks National Marine Sanctuary.
‘To support robust industry participation, lower production costs, and unleash the full potential of the Gulf of America’s offshore energy reserves, BOEM is proposing a royalty rate of 16% for both shallow and deepwater leases – the lowest rate for deepwater since 2007,’ said BOEM’s acting regional director for the Golf of America Laura Robbins.
Publication of PNOS on 27 June 2025 initiated a 60-day comment period for the affected state governors and local governments. After the comment period, BOEM will issue a Final Notice of Sale in the Federal Register at least 30 days before the scheduled public bid reading, proposed for 10 December 2025.
Two new subsea templates (marked in yellow) and the existing infrastructure from phases 1 and 2.
Fugro wins geophysical contract for offshore wind farms in German North Sea TGS completes OBN survey in Gulf of America
TGS has completed the Amendment Phase 4 ultra-long offset ocean bottom node (OBN) survey in the Gulf of America.
The project covers 49 outer continental shelf (OCS) blocks across the Mississippi Canyon and Ewing Bank protraction areas, providing valuable insight for companies preparing for anticipated lease rounds as early as the second half of 2025.
For the first time in the Gulf of America, TGS deployed its proprietary Gemini enhanced-frequency seismic source in an ultra-long offset acquisition setting. Gemini delivers a unique low-frequency, omnidirectional signal that, combined with advanced processing techniques, is said to significantly improves illumination beneath complex salt bodies.
David Hajovsky, executive vice president of multi-client at TGS, said: ‘The successful use of the Gemini low-frequency source in this programme marks a step forward in delivering greater subsurface clarity while meeting evolving industry expectations around responsible operations.’
Fugro has won contracts to conduct both geophysical and geotechnical site investigations for two large-scale offshore wind farms in the German North Sea. The project, known as Windbostel Ost and Windbostel West, is a joint venture between RWE and TotalEnergies, with a combined generating capacity of 4GW.
Fugro will provide geo-data on the seabed and subsurface conditions northwest of the island of Borkum. The geophysical surveys will provide initial detailed mapping of the seabed and shallow subsurface layers, identifying potential hazards and informing early design considerations.
Federal Maritime and Hydrographic Agency (BSH).
After the May 2025 release, which covered the Uinta, Piceance, and Paradox basins, the new dataset delivers regional subsurface insights across more than 4000 wells and includes 59 stratigraphic tops, 29 of which account for repeated occurrences in the thrust belt. The release also includes detailed petrophysical interpretations and regional property maps, supporting both traditional and emerging energy workflows.
The Amendment 4 early-out product will be available in the third quarter of 2025, with final data delivery expected in the second quarter of 2026.
Meanwhile, TGS has released a stratigraphic and petrophysical dataset for the Greater Green River Basin (GGRB) in Wyoming, onshore US, further expanding its Rocky Mountain data portfolio.
The geotechnical investigation will provide data on the seabed’s soil composition and characteristics through in situ testing and sampling. The combined geophysical and geotechnical data will inform foundation design, structural analysis, cable routing, and risk assessment during the construction and operational phases of the project.
This contract follows Fugro’s previous geotechnical investigations for the 1.6 GW Nordseecluster project (RWE share: 51%) in Germany and builds on preliminary geotechnical data acquired by Fugro for the German
Designed for ‘maximum utility and technical integrity’, the dataset enables consistent regional stratigraphic interpretation across structural and depositional complexities, petrophysical analysis of key reservoir characteristics such as porosity and fluid saturation, basin-wide property mapping, facilitating prospect evaluation, reservoir modelling, and carbon storage screening.
The GGRB dataset supports a wide range of subsurface applications, from hydrocarbon extraction to carbon storage assessment. It is built to integrate seamlessly into existing workflows, offering a standardised foundation for geoscientists, engineers, and decision-makers focused on regional exploration and energy transition strategies.
Fugro Zenith vessel.
David Hajovsky, executive vice president of multi-client at TGS.
The use of gaming and geodata visualisation in preparation for high Arctic research fieldwork
Daniel Kramer1,2, Marius Opsanger Jonassen3, Kim Senger3, Rafael Kenji Horota3 and Solveig Solem 4
Abstract
Fieldwork is essential in many scientific disciplines, providing critical data for validating simulations and ground truthing. However, fieldwork is often costly, logistically challenging, and may require travel to remote or hazardous locations, necessitating thorough preparation and safety measures. Training in fieldwork skills begins at the university level, but proficiency is gained through experience over time.
The University Centre in Svalbard emphasises Arctic fieldwork, integrating classroom instruction with on-site training. To enhance student preparation, we developed games and visualisation tools to help anticipate and manage fieldwork challenges. This article showcases several video games and outlines a guide for creating a video game using various data sources — satellite and aerial imagery, point clouds from remotely piloted aircraft systems (RPAS) — to explore Svalbard’s landscape.
This versatile approach can be adapted to other regions or applications. Geographic Information Systems (GIS) are used to create thematic games, and we demonstrate visualisation techniques for teaching, publications, and outreach, including Virtual Reality (VR). Additionally, we explain how handheld LiDAR can scan and incorporate small local areas into the games, and how Micro-CT data can be used to explore microscale environments, such as a virtual flight through a snowpack. All methods use open-source products, or products with a limited, but free licence.
Introduction
Fieldwork is fundamental to geoscientific research. Its primary goal is data collection, usually demanding knowledge on how to interpret information on-the-spot (Frodeman, 1995). However, fieldwork is often costly, involving expenses for travel, accommodation, and shipping equipment. It requires training and oversight to line all these factors up for a successful campaign. Strict safety measures are often required to mitigate risks posed by natural hazards and wildlife. Similarly, this requires training and familiarisation with the given environment. Further concerns may arise: It could be remote sites that require far travels (environmental concern) or the inaccessibility of a site (e.g. for individuals with disabilities).
To address these topics, the use of video games for geoscientific purposes has rapidly evolved. Video games have been gaining recognition in conference programs, such as the European Geoscience Union General Assembly, to demonstrate the potential of games (Skinner and Stanford, 2020). For instance, Skinner (2020) created a game aimed at raising public awareness of flood risks and geomorphology. Pringle (2013) discovered
that e-games motivate students to engage more deeply with an academic publication if the material is complemented by a video game.
At the University Centre in Svalbard (UNIS; 78° N), fieldwork is central to its educational mission. Courses are taught year-round despite the complete darkness of polar night and harsh Arctic winter conditions. Many students arrive with neither fieldwork nor Arctic experience, and preparation focuses not only on teaching science, but also on safety and preparedness. Numerous resources are available to teach the basics, such as the INTERACT guidebook (INTERACT, 2021), Google Earth, and toposvalbard (https://toposvalbard.npolar.no). These resources offer general guidance for behaviour in the field, but also maps, aerial images, and coordinates.
For more immersive planning, platforms such as Google Earth VR, Svalbox (svalbox.no/map; Senger et al., 2022; Betlem et al., 2023), and VRSvalbard (https://vrsvalbard.com) are available. In geology, Digital Outcrop Models (DOMs) are widely used (Senger et al., 2021 and references therein), particularly when combined with regional geoscientific data (Horota et al., 2023).
1 Université de Sherbrooke | 2 Centre d’études nordiques’ (CEN) | 3 University Centre in Svalbard
Figure 1 On top: This is the bird’s-eye view of the main level of the game. The user can walk over Svalbard and look at a combination of a geological map blended with an orthophoto. The lower image is a sublevel with a higher resolution and more details.
We use a combination of QGIS and Blender to create a digital 3D model of a landscape. Other software is available to create 3D models via Structure-from-Motion. This is a common technique and will not be explained further.
We used the QGIS plugin ‘DEMto3D’ to print several blocks, which we assembled into a broader landscape. Then we projected an image or video onto the printed landscape. This process was used in the Svalbox project (Betlem et al., 2023) to visualise data.
Blender Blender can render an image and videos of a scene by placing a 3D model, a camera, and a light source.
– 3D content: Stereoscopic camera (Eevee engine) – 360° content: Camera (Cycles engine) – Audio-content, video effects and video editing
VR environments Blender Blender's VR add-on, paired with a VR headset/controller, provides interactive 3D scene exploration, useful for educational tasks like virtual instrument placement, route planning, or exams.
Holographic displays Blender We implemented a holographic display, which allows us to show 3D scenes without needing a VR headset.
As a certain percentage of people experience discomfort with VR headsets (e.g., nausea, dry eyes), this is a different solution to displaying 3D content.
Additionally, this method allows for discussion in a team around a single display.
Games Blender, Unreal Engine We imported or created different 3D models in Blender. The models were transferred to Unreal Engine to create thematic video games. We have published one game as an example (Kramer et al., 2022b)
Table 1 Summary of different methods and steps.
These tools help participants to build a mental map of the environment and its challenges, connecting field sites before and after field campaigns. To enhance fieldwork teaching, we developed materials and games that allow students to explore Longyearbyen and its surroundings, as well as the remote loca-
Instructions
– Kramer et al. (2022a)
– DEMto3D manual
– Manuals of software provider (in our case: SHAPEwerk)
– Kramer and Jonassen (2022)
– Countless tutorials on platforms like YouTube
– The VR-add-on is part of Blender and can be activated in the settings.
– Requires a holographic display. We used the ‘Looking glass Portrait’ which comes with a Blender add-on and a manual.
– Kramer et al. (2022a)
tions related to their courses. We used Geographic Information Systems (GIS) to create Digital Surface Models (DSM) and textures, incorporating data from various sources (Remotely Piloted Aircraft Systems, aerial and satellite imagery, LiDAR, X-Ray). Students can use the materials created individually (e.g.
game, VR) or experience it with a group through a holographic display or projector (with a 3D-printed ‘canvas’), creating realistic visualisations of research sites.
This article provides an overview over several games that we have built and a guide for creating such a game for any research site and presents two games developed using the demonstrated techniques. We further showcase various methods for visualising geodata, which can be easily incorporated during the game development. All visualisation techniques can be adapted for teaching materials or publications, including 3D images, videos, VR applications, and for holographic displays.
Methodology
To create 3D models of geographic landscapes, height information and textures (images of the landscape) are required. We utilised different sources (satellite, aircraft, RPAS, LiDAR) in our educational games; a fourth method (computer tomography) was used to visualise a snow sample, reflecting the microscale component of geosciences. Table 1 summarises the methods to recreate different types of visualisation. Workflows and examples are compiled in Kramer (2025).
Results
The following sections present a selection of existing video games that have been created to visualise and interact with various geoscientific concepts and phenomena. These examples illustrate the potential of interactive digital environments as engaging tools for geoscience education and outreach.
A game to visit sites with global geoscientific significance
Users can visit several sites of global geoscientific significance: The Festningen profile in western Spitsbergen offers easy access to 300 million years of Earth’s history, including a complete succession across the Permian-Triassic boundary. This interface represents the largest mass extinction in Earth’s history, driven by widespread magmatism at the Siberian Traps. A virtual visit to the site using the geology game is complemented with a high-resolution digital outcrop model of the entire section (Senger et al., 2022) and thematic web-based photosphere-based virtual field trips (Horota et al., 2024). The game is available via Kramer (2022).
In the game, users can virtually navigate a coarse-resolution model of Svalbard, enabling exploration of different geological sites. This facilitates the development of a spatial understanding of regional geological features and their geographic relations. High-resolution sublevel provide site-specific and detailed views. Both the coarse and high-resolution models are derived from the same source data but use distinct export parameters to achieve varying levels of detail. Screenshots of the interactive environment are presented in Figure 1.
Billefjorden Trough – a frequently visited site
The Billefjorden Trough is one of the most visited field sites in Svalbard, presenting an exposed Mid-Carboniferous half graben and its heterogeneous basin fill. Ongoing research on refining the tectono-stratigraphy of the basin (e.g., Smyrak-Sikora et al.,
2019; 2021) and yearly UNIS-led geoscientific excursions both in spring and summer (Senger et al., 2021) have generated a wealth of geoscientific data. Photospheres and digital outcrop models can be integrated with digital terrain models, geological maps, cross-sections and complementary field data to investigate all aspects of the Billefjorden Trough.
Given the global coverage by datasets such as ArcticDEM and platforms like Google, initial mission planning commences with a coarse-resolution survey to establish a general understanding of the operational area. This approach has a reduced spatial resolution but allows for rapid familiarisation from the office or at home. This is helpful especially for activities like operating a drone.
The next iteration is drone-based data acquisition, providing significantly enhanced spatial resolution, serving to refine site characterisation. Other data acquisitions accompany this step. Figure 2 shows screenshots from the game.
This methodology can be further scaled down to encompass localised investigations utilising handheld cameras, as demonstrated by Meloche et al. (2020), who achieved meter-scale tundra roughness characterisation with sub-millimetre accuracy (0.1 mm).
For an institution like UNIS, which revisits sites on an annual basis, this example allows us to collect and digitise data over years, improving the resolution of the digital model and the reservoir of data available for future generations of students. It allows us to select a specific site or analyse the temporal changes.
Figure 2 Top: The coarse version based on the ArcticDEM. Bottom: The drone-based version with a higher resolution.
Avalanche danger and Glacier Mass Balance
Prior to any fieldwork in avalanche-prone terrain, a thorough assessment of avalanche danger is paramount for safety. This evaluation, encompassing factors such as snowpack stability, recent weather patterns, and terrain morphology, is critical for mitigating the risk of avalanches. An inadequate assessment of the field site can expose students/ researchers to hazards that could lead to serious injuries or fatalities.
Direct observation and testing of the snowpack are essential for accurate risk assessment and cannot be replaced by any virtual model. Nevertheless, the 3D model serves as a preparatory instrument, providing a spatial overview of terrain features that may contribute to avalanche danger, thereby informing the selection of safe travel routes and highlighting areas requiring heightened scrutiny during field assessments. Figure 3 shows a screenshot of the virtual environment.
In our courses, students receive basic Geographic Information System (GIS) training through an introductory course (Kramer, 2023; free download). The safety assessment component is followed up with scientific content, as exemplified by our ‘Mass Balance Game’ (Kramer et al., 2022b). This interactive simulation, built upon the principles described in this article, incorporates in-game videos and explanations of glacier mass balance concepts and fieldwork preparation requirements. In-game screenshots are presented in Figure 4.
Other examples
We would like to point out the large variety of possible applications for educational video games to visit different geographic locations, scales, and geoscientific content.
During the International Arctic Snow School in April 2023 in Cambridge Bay (Nunavut, Canada), we 3D-scanned several snow pits using an iPhone 14 Pro and integrated the data into a
Figure 3 The 3D model has an overlay of an aerial image and an indicator of the steepness of the slope. The colours are selected on an official classification of avalanche danger due to the steepness of the terrain (low danger: green, intermediate danger: orange, high danger: red).
Figure 4 In-game content for the ‘Mass Balance Game’. The upper figure shows a video of a teacher giving instructions. The lower figure is a dialogue between the user and a non-playable character (NPC).
showcase video game. The user can roam around on a general map and then enter a sublevel of the game with collected data from a snow pit (Figure 5).
We created another game for a meteorology course. It features the main level ‘Isfjorden’, which connects all field sites, mirroring real-life boat access. Each field site corresponds to a sub-level with higher-resolution terrain and specific topics. Figure 6 (top) displays the modelled Nostoc field station, while Figure 6 (bottom) presents a simplified weather station model.
The above examples focus on larger spatial scales. However, we also explored the micro-scale of geoscientific work. The presented snow sample was collected during a research campaign
Figure 5 The in-game screenshot displays the 3D-scanned snow pit along with scientific data collected by snow school students.
Figure 6 The upper figure depicts the Petuniabukta sublevel of the game, a model of the Nostoc research station and a large box containing various maps and information on cloud types for students to explore. The lower figure shows a 3D model of a weather station that users can explore. The farther ground is based on orthophotos, while the nearer ground is derived from RPAS flight photos.
in April 2022 in Cambridge Bay (NU), Canada. This dataset was provided by colleagues from Northumbria University (Newcastle, UK) and the Institute for Snow and Avalanche Research (SLF) in Switzerland. We animated a flight through the structure of the snow. The video can be found in Kramer (2025). An additional video of a static scene of the same snow sample displayed on a holographic display can be found there as well.
Discussion and conclusions
For large-scale analyses, such as virtual visits to sites of global geoscientific significance, methodologies using datasets like ArcticDEM offer the distinct advantage of online availability and,
in this instance, cost-free access. This characteristic enhances accessibility for a broad user base. For the remaining terrestrial regions, elevation data is readily obtainable through sources such as the Shuttle Radar Topographic Mission. In conjunction with platforms like Google Maps, OpenStreetMap, and governmental institutions such as the Norwegian Polar Institute, the digital modelling of nearly any global area is feasible.
Nevertheless, this approach of terrain modelling presents several challenges that affect the accuracy of 3D representations. One key issue arises from subdividing the initial plane in Blender, which distorts the original height data. The level of distortion depends on the number of sub-planes, which influences the model’s shape and detail. While the landscape remains largely accurate, finer details may be compromised. Other artefacts like warping at the edges of the plane or obelisk-like structures are time-consuming to remove.
The method performs well on smaller scales, capturing terrain details accurately. This is difficult to apply to larger areas, due to hardware limitations (we used a high-end gaming laptop), which struggle to process a large datasets in high resolution.
While the GIS-based approach offers potential for terrain modelling, these technical limitations present challenges in achieving high-quality, distortion-free results at larger scales.
For enhanced spatial detail or precise representations, such as visualising geological outcrops for pedagogical purposes, dedicated funding and time are necessary for data acquisition and subsequent processing. However, for frequently visited sites, such as those integrated into the UNIS coursework, the digital capture allows for the documentation of temporal changes. Public online dissemination of these datasets enables a broader audience to observe the activities of scientists and students.
It is crucial to emphasise that virtual fieldwork approaches cannot supersede or replace in-situ fieldwork. This is particularly important in scenarios where the safety of the field team is a primary concern. For instance, digital representation of avalanche-prone terrain does not obviate the necessity for on-site evaluation of snowpack stability to ascertain the safety of a working area.
This article outlined methods for visualising and gamifying geodata, providing immersive ways to present research sites and fieldwork tasks. Students can utilise these games to prepare for fieldwork, offering an interactive approach to geoscience education. From a pedagogical perspective, the game teaches key concepts such as glaciology, glacial mass balance, field workflows, and data management.
Acknowledgements
This project has been partially funded by the Center for Integrated Earth Science Education (iEarth).
We would like to thank UNIS for funding most of our field activities and the Czech Research Station Nostoc for hosting us.
We would also like to thank the Groupe de Recherche Interdisciplinaire sur les Milieux Polaires (G.R.I.M.P.) for its contributions.
For providing freely available data, we want to thank the Norwegian Polar Institute, ReMoTE-Nord (Université du Québec à Trois-Rivières), and the Polar Geospatial Center (University of Minnesota).
We would further like to thank students from the Arctic Snow School 2023 for their contributions.
Nick Rutter and Melody Sandells from Northumbria University collected micro-CT samples, which Matthias Jaggi and Henning Löwe analysed at the WSL Swiss Institute for Snow and Avalanche Research SLF. Their work was funded under the ESA AKROSS project, ESA CONTRACT No. 4000130073/20/I-DT and was only possible thanks to logistical support from the Canadian High Arctic Research Station and Polar Knowledge Canada.
We want to thank the QGIS development team and the Blender Foundation for providing their open-source software to everyone. For some of the used materials, we want to thank the developers behind ‘BlenderKit’. Further, we want to thank Epic Games (UE5) for offering a licence that allows users to work with their software for free for non-commercial/research purposes.
References
Betlem, P., Rodes, N., Birchall, T., Dahlin, A., Smyrak-Sikora, A. and Senger, K. [2023]. The Svalbox Digital Model Database: a geoscientific window to the Arctic. Geosphere, 19(6), 1640-1666. DOI: 10.1130/GES02606.1.
Frodeman, R. [1995]. Geological reasoning: Geology as an interpretive and historical science. Geol. Soc. Am. Bull., 107, 960–968. https://doi. org/10.1130/0016- 7606(1995)107%3C0960:GRGAAI%3E2.3.CO;2.
Horota, R.K., Senger, K., Smyrak-Sikora, A., Furze, M., Retelle, M., Vander Kloet, M.A. and Jonassen, M.O. [2024]. VRSvalbard: A photosphere-based atlas of a High Arctic geo-landscape. First Break, 42(4). https://doi.org/10.3997/1365-2397.fb2024029.
Horota, R.K., Senger, K., Rodes, N., Betlem, P., Smyrak-Sikora, A., Jonassen, M.O., Kramer, D. and Braathen, A. [2023]. West Spitsbergen fold and thrust belt: A digital educational data package for teaching structural geology. Journal of Structural Geology, 167, 104781. https://doi.org/10.1016/j.jsg.2022.104781.
INTERACT. [2021]. INTERACT Fieldwork Communication and Navigation, Eds.: Schneider, A. et al. DCE – Danish Centre for Environment and Energy, Denmark, 80.
Kramer, D. [2022]. Svalbard Geology Game. Zenodo. https://doi. org/10.5281/zenodo.8033566.
Kramer, D. and Jonassen, M. [2022]. FROST – A video about the videos. Zenodo. https://doi.org/10.5281/zenodo.7997495
Kramer, D., Jonassen, M. and Solem, S. [2022a]. iWalk on FROSTHow to create a walkable map. Zenodo. https://doi.org/10.5281/ zenodo.7997493.
Kramer, D., Jonassen, M. and Solem, S. [2022b]. Mass Balance Game. Zenodo. https://doi.org/10.5281/zenodo.7997591.
Kramer, D. [2025]. Accompanying materials for publication: The Use of Gaming and Geodata Visualization in Preparation of High Arctic Research Fieldwork. Zenodo. https://doi.org/10.5281/zenodo.15287147.
Meloche, J., Royer, A., Langlois, A., Rutter, N. and Sasseville, V. [2020]. Improvement of microwave emissivity parameterization of frozen Arctic soils using roughness measurements derived from photogrammetry. International Journal of Digital Earth, 14(10), 1380–1396. https://doi.org/10.1080/17538947.2020.1836049.
Pringle, J.K. [2013]. Educational environmental geoscience e-gaming to provide stimulating and effective learning. Planet, 27(1). https://doi. org/10.11120/plan.2013.27010021.
Senger, K., Betlem, P., Birchall, T., Gonzaga, L., Grundvåg, S.-A., Horota, R.K., Laake, A., Kuckero, L., Mørk, A., Planke, S., Rodes, N. and Smyrak-Sikora, A. [2022]. Digitising Svalbard’s Geology: the Festningen Digital Outcrop Model. First Break, 40(3), 47-55, https:// doi.org/10.3997/1365-2397.fb2022021.
Senger, K., Betlem, P., Grundvåg, S.A., Horota, R.K., Buckley, S.J., Smyrak-Sikora, A., Jochmann, M.M., Birchall, T., Janocha, J., Ogata, K. and Kuckero, L. [2021]. Teaching with digital geology in the high Arctic: opportunities and challenges. Geoscience Communication, 4(3), 399-420, https://doi.org/10.5194/gc-4- 399-2021.
Skinner, C. [2020]. Flash Flood!: a SeriousGeoGames activity combining science festivals, video games, and virtual reality with research data
for communicating flood risk and geomorphology. Geosci. Commun., 3, 1-17, https://doi.org/10.5194/gc-3-1-2020.
Skinner, C. and Stanford, K. [2020]. Games for Geoscience. Nat. Rev. Earth Environ., 1, 188, https://doi.org/10.1038/s43017-020 -0043-0.
Smyrak-Sikora, A., Johannessen, E.P., Olauseen, S., Sandal, G. and Braathen, A. [2019]. Sedimentary architecture during Caboniferous rift initiation – the arid Billefjorden Trough, Svalbard. Journal of the Geological Society. https://doi.org/10.1144/jgs2018100.
Smyrak-Sikora, A., Nicolaisen, J.B., Braathen, A., Johannessen, E.P., Olaussen, S. and Stemmerik, L. [2021]. Impact of growth faults on mixed siliciclastic-carbonate-evaporite deposits during rift climax and reorganisation—Billefjorden Trough, Svalbard, Norway. Basin Research, 33(5). https://doi.org/10.1111/bre.1257.
3rd EAGE/SUT Workshop on Integrated Site Characterization for Offshore Renewable Energy
Step into the heart of offshore renewable energy innovation, where cutting-edge research meets actionable solutions. Join global pioneers at the 3rd EAGE/SUT Workshop on Integrated Site Characterization in dynamic Melbourne , Australia. From floating wind farms to smarter seabed surveys, this is your platform to drive real impact.
ENVIRONMENT, MINERALS AND INFRASTRUCTURE
Submit an article
This month we feature some of the papers that will be featured at the EAGE Near Surface Geoscience conference in Naples, Italy on 7-11 September. The conference will also feature five parallel programmes covering: Environmental and Engineering Geophysics; Mineral Exploration and Mining; Infrastructure Planning, Monitoring and BIM; Geohazards Assessment and Risk Mitigation; and UXO and Object Detection. Reflecting the broader theme of this issue, which has been renamed Environment, Minerals and Infrastructure, participants at the conference will have the opportunity to explore a wider range of subjects and innovative approaches, opening new avenues for growth within geosciences.
Vetle Vinje et al investigate a novel UHR configuration deployed during a field test in June 2024 offshore Concarneau in France where a deep streamer was towed underneath a new sparker source.
Joy Muraszko presents radiocarbon dating results from eight cores in the Rakhine Basin, building on previous geophysical interpretations and coring efforts to focus on turbidites and mass transport deposits for geohazard assessment.
Giorgio De Donno et al present an application of a global inversion approach based on the Very Fast Simulated Annealing (VFSA) algorithm to ERT and IP datasets acquired on a municipal solid waste (MSW) landfill located in Central Italy.
Ana Abreu et al present the experimental procedure used to estimate the fundamental period of the soil, Tsoil, which is based on the horizontal- to-vertical spectral ratio (HVSR) method, and the fundamental period of the wind tower, Ttower, based on the top-to-base horizontal spectral ratio (HHSR) method proposed by Álvarez (2025).
First Break Special Topics are covered by a mix of original articles dealing with case studies and the latest technology. Contributions to a Special Topic in First Break can be sent directly to the editorial office (firstbreak@eage.org). Submissions will be considered for publication by the editor.
It is also possible to submit a Technical Article to First Break. Technical Articles are subject to a peer review process and should be submitted via EAGE’s ScholarOne website: http://mc.manuscriptcentral.com/fb
You can find the First Break author guidelines online at www.firstbreak.org/guidelines.
Special Topic overview
January Land Seismic
February Digitalization / Machine Learning
March Reservoir Monitoring
April Underground Storage and Passive Seismic
May Global Exploration
June Navigating Change: Geosciences Shaping a Sustainable Transition
July Reservoir Engineering & Geoscience
August Environment, Minerals and Infrastructure
September Modelling / Interpretation
October Energy Transition
November Marine Acquisition
December Data Management and Processing
More Special Topics may be added during the course of the year.
Ultra high-resolution shallow marine imaging with a sparker over a deep streamer
Vetle Vinje1, Florian Josse2, Thibaut Choquer3, Peng Zhao1, Isabelle Thauvin 4, Patrick Charron 5 and Philippe Herrmann2 investigate a novel UHR configuration deployed during a field test in June 2024 offshore Concarneau in France where a deep streamer was towed underneath a new sparker source.
Introduction
Ultra high-resolution (UHR) marine seismic is a scaled-down version of conventional seismic acquisition. Source-receiver separation and depth, shooting rate and seismic wavelengths are typically ten times smaller than for conventional seismic operations. Under ideal conditions, ten times higher subsurface resolution may be achieved, but there will also be less depth penetration due to anelastic damping of the high-frequency seismic waves.
While UHR marine seismic has traditionally been used for geohazard mapping for the oil and gas sector, it has gained popularity in recent years to map boulders, shallow gas and geomechanical properties in the shallow water bottom for offshore windfarm planning. Both 2D and 3D UHR applications have been used (Telling et al., 2024, Davies et al., 2020, Lebedeva-Ivanova et al., 2018)
One common drawback of the typical UHR survey configuration aiming to achieve frequencies above 1000 Hz relates to the shallow tow of the hydrophone streamers (0.5 to 1 m depth). This makes them vulnerable to adverse weather conditions, leading to significant downtime. Furthermore, the signature of sparker sources has notches in their spectra (Kluesner et al., 2019) and the source wavelet is typically not measured directly; making it hard to estimate. In this paper, we will investigate a novel UHR configuration deployed during a field test in June 2024 offshore Concarneau in France where a deep streamer was towed underneath a new sparker source. We will compare images of the shallow geology using this novel source-over-streamer configuration with a traditional UHR configuration where the streamer was towed at a shallow depth behind the source acquired along the same 2D line. Both surveys were processed and imaged by the same group using the same toolbox of technologies.
1 Viridien | 2 Sercel (a Viridien Business) | 3 Kappa | 4 SIG | 5 TotalEnergies
Figure 1 Map of the survey area close to Concarneau with the acquisition line in blue.
Source type SIG KappaSpark sparker
Source characteristics 1400 J, 200 tips, single level
Shot spacing ~ 1.8 m
Source depth ~ 0.6 m
Nav system
Depth control and recorders
Sercel Concept Orca
Sercel Nautilus system
Surface positioning system Fugro Citius RGPS
Streamer type
Sercel UHR streamer
Sensor type Dual hydrophone array
Streamer length
Number of channels 48
Channel separation 3.125 m
m
Temporal sampling rate 0.25 ms (2000 Hz nyquist frequency)
Seismic surveys offshore Concarneau
The field test was initiated by Sercel, Kappa Offshore, SIG and TotalEnergies and conducted on 19-20 June 2024 offshore Concarneau in Brittany, France (Figure 1).
The geology in the area is formed by a tectonic Eocene depression later draped by late Pleistocene and 3-5 m thick Holocene sediments (Flamme et al., 2020). The Eocene series are faulted and folded, while the upper sedimentary layers are characterised by biogenic gas generated by bacterial activity in the sediments rich in organic material. This gas is present as a multitude of shallow gas pockets and has also outgassed at the
2 The UHR seismic survey geometries from the field test compared in this study; (a) a conventional acquisition and (b) a source above a deep streamer acquisition.
seabed, creating myriads of shallow pockmarks that are typically 30 m wide and 2-3 m deep (Dusart et al. 2022).
The trajectory of the two straight ~10 km 2D test lines from June 2024 described in this paper is shown as the blue line in Figure 1 and runs over water depths of 30-40 m. We will compare seismic images from two acquisition configurations: (i) a conventional UHR survey geometry with a shallow streamer towed behind the source and (ii) a survey geometry where the source was towed above a deep streamer, as shown in Figure 2a and 2b respectively.
We refer to these as the Conventional and Novel surveys throughout this paper. They were acquired with the same equipment and the same lateral and temporal sampling, as shown in Table 1.
Although the source-over-spread concept has been successfully applied in conventional seismic in the search for hydrocarbons (Vinje et al., 2017, Camerer et al., 2018), it has not been documented or published for UHR seismic.
In the Novel survey in Figure 2b the source was located directly above the deep streamer at around 8 m in depth. The actual shape of the streamer sagged slightly in the middle with depths varying between 7 and 9 m. Both the Conventional and the Novel tests were run with the same source, the same UHR streamer, and the same spatial and temporal sampling rate, as shown in Table 1.
The sparker source
The sparker used in both surveys is a SIG KappaSpark sparker specifically designed for this field test. The 200 sparker tips were
Figure
Table 1 Common acquisition parameters for the Conventional and Novel test lines.
Figure 3 The sparker source used in the Conventional and Novel surveys.
arranged in one single layer. The photo of the source in Figure 3 shows the aluminium frame with the 200 tips arranged in a 1 × 0.42 m rectangular pattern.
When the sparker is fired, a small bubble consisting of water vapour and plasma is formed at each of these tips, resulting in a downgoing acoustic wave in the water column. The torpedo-like yellow float keeps the frame with the 200 tips at a depth of ~0.6 m beneath the sea surface.
The source-over-streamer Novel configuration provided the opportunity to achieve an accurate source signature estimation, which was a requirement for a good de-signature processing of the data.
This source position is illustrated in Figure 4. In Figure 4a, the sparker source at a depth of ~0.6 m was located above the streamer towed at a depth of ~8 m where the downgoing seismic wave is recorded. Streamer channel 18 was located directly beneath the sparker source. Figure 4b shows the downgoing direct wave for 26 channels centred around channel 18. The zoom of the three central downgoing pulses shows a short-duration Ricker-like wavelet with a frequency spectrum shown in Figure 4c. This wavelet is a combination of the direct wave from the sparker tips and the reflections from the sea surface (i.e. the source ghost) and scattering from the sparker float above the sparker tips. In the frequency spectrum in Figure 4c we observe a notch at ~1250 Hz which was caused by the source ghost and corresponds to the source depth of 0.6 m. A favourable property of the sparker used in this field test is its short duration (~3 ms) and the absence of notches in the usable spectrum. Notches in the spectra of sparkers are caused by the bubble energy which is a well-known phenomenon in sparker sources and is caused by a second expansion of the initial expansive water vapour bubble (Kluesner et al., 2019). As shown in Kluesner et al (2019), conventional sparker sources with similar energy levels as in the SIG KappaSpark exhibit a much larger bubble lag, creating a long-duration source wavelet in the time domain and several notches in the spectrum which are a problem in the de-signature of the seismic data. In the SIG KappaSpark, the lag between the main peak and the bubble is so small that the first bubble notch occurs above the highest usable frequency in the data.
Another favourable property of the new sparker source is the lack of directivity of the source signature including the source ghost. In Figure 4b we observe that the wavelet for central channel 18 directly beneath the source is similar to the wavelets for its
neighbouring channels 17 and 19 which have energy departing from the source at an angle of about 25 degrees from the vertical. Usually, we would expect a significant variation in the wavelet, mainly due to the tuning between the primary and the ghost. In this case we do not observe this, and we speculate that it may be caused by the scattering effect of the float carrying the sparker source.
This lack of directional diversity, the lack of bubble notches and the measurement of the downgoing vertical source wavelet (including its ghost) simplified the source de-signature and de-ghosting processes. In the processing workflow we used a single deconvolutional filter to de-signature, source de-ghost and shape the data to a desired spiky wavelet honouring the observed signal-to-noise (S/N) ratio.
Figure 4 The direct seismic pulse from the sparker source (a) is recorded in the deep UHR streamer. The split-spread direct-wave recording is presented in (b) with a zoom of the central three pulses. In (c) the spectrum of the central pulse is displayed.
Figure 5 A shot gather with a firing problem, showing the direct wave, the water bottom reflection and the electromagnetic event used to correct the trigger error of the shot.
Correcting source timing and source/receiver positions
During QC of the field data, it was discovered that the firing time of the sparker source was out of sync with the instructed trigger time due to an unexpected extra charging time for the sparker capacitor. Mostly, the firing error was limited to less than a millisecond, but for some of the shots it was 30 ms or more. An example of this is shown in Figure 5 where a shot gather from the Novel survey is displayed. We can see the direct arrival and the water bottom reflection. However, we can also see that the apex of the direct wave in Channel 18 arrives at around 35 ms, which is not consistent with the vertical distance of around 7 m between the source and Channel 18. The direct traveltime for these 7 m in water should be around 5 ms. To correct the trigger error, we used a fortunate side-effect of the sparker source. When the sparker source was fired, the electromagnetic field surrounding it created a weak and almost simultaneous response in all the channels in the streamer. This was not caused by any acoustic wave in the water but was purely a response in the electronic systems in the streamer to the electromagnetic field in the water. This electromagnetic (EM) event is labelled in Figure 5.
The trigger error was corrected with the following three steps:
1. Stack the traces in each shot gather to create a single trace for each shot where the weak EM event will be enhanced and clearly visible.
2. From the stacked traces, select an ‘anchor trace’ with an estimated correct trigger time and measure the time lag of the electromagnetic event from all the other traces.
3. Shift all shot gathers to the anchor trace with the measured time lags.
Once the trigger error had been corrected, it was possible to accurately pick the first-break traveltime of the direct wave from the source to each of the channels. These traveltimes were used to derive the source-channel distance for each shot point using the water velocity of 1508 m/s which was found using a separate inversion process based on the direct arrivals. The distance from the source to the channel directly below (Channel 18) was measured along the entire sail-line. Channel 18 in the streamer was located vertically beneath the source as the sparker and streamer moved across the test line. It is reasonable to assume that the rapid variations in this source-to-channel distance observed
along the sail line were caused by the up-and-down movement of the source due to sea waves and swells. We corrected for these rapid vertical wave-generated shifts in the source using a static shift which significantly reduced the jitter in the data, as shown in Figure 6.
Four zooms of a common channel gather for Channel 18 are displayed in Figure 6. About 85 m of the test line is shown in these zooms. Figures 6a and 6b show the direct wave before and after correction of the wave motion. We notice that a jitter of up to around 0.4 ms is observed in Figure 6a, which was corrected in Figure 6b by a static shift. This corresponds to a vertical movement of up to +/- 30 cm which is consistent with the wave height reported on the day of acquisition on 20 June, 2024 and illustrates the high level of accuracy required for the vertical source location on UHR surveys. After this correction, we show that the jitter had been removed on the direct wave (Figure 6b). Also, the jittering of the water bottom reflection was improved from before (Figure 6c) to after (Figure 6d) the correction. The water bottom reflection still contained noticeable lateral variations caused by the water bottom geology, as expected.
The remaining slowly varying source-to-channel distance was subsequently used to estimate the depth of the streamer, which was crucial in the receiver de-ghosting and imaging – see the discussion hereafter.
Designature and deghosting
We will now describe the solutions to two challenging problems inherent in UHR survey processing, (i) source deghosting and designature and (ii) receiver deghosting. The aim of these processing steps is to achieve a result with spiky, symmetrical reflectors with no remaining ghosts.
With the measurement of the direct wave in the Novel survey, as shown in Figure 4b, and the favourable lack of directionality of the sparker source, it was straightforward to create a 1D filter that performed the source deghosting, and shaped the data to a broadband, zero-phased, spiky wavelet taking into account the spectral S/N level. The shaping/source-deghosting filter was limited to frequency range with acceptable S/N levels, namely between ~150 Hz and ~1600 Hz. We refer to this process as source designature, as it removed the effect of the source wavelet and its ghost and shaped the wavelet.
The receiver deghosting, however, was potentially a more challenging problem to solve. Conventional UHR surveys typically lack accurate measurements of the streamer depth which is crucial for effective deghosting. In these cases, picking spectral notches in the data (Provenzano et al., 2020) is an option, but this may be challenging for noisy data. With the deep streamer in the Novel survey, the receiver ghosts (i.e. the downgoing sea-surface reflection of the seismic data) arrived as events that were completely separated from the upgoing primaries. This is clearly visible in Figure 7a, which shows the channel gather for Channel 18 before source designature and receiver deghosting.
All the subsurface reflectors in the data were ghosted, including the water bottom reflection indicated by the white arrow in Figure 7a. Its ghost (red arrow) arrived at around 10 ms after the water bottom primary reflection, which is consistent with the streamer depth of 8 m (2×8 = 16 m two-way vertical
Figure 6 Common-channel (Ch 18) traces from the direct wave (a) and (b) and water bottom reflection (c) and (d) before and after correction of the source shifts due to wave motion.
distance divided by 1508 m/s water velocity). Figure 7b shows the common channel gather after the source designature and receiver deghosting. We first notice that the water bottom is spiky, with weak sidelobes and limited ringing, suggesting an accurate source designature.
The receiver ghost was modelled (Poole, 2013) using the corrected streamer depth from the Novel source-over-streamer setup and was adaptively subtracted from the data. The receiver ghosts were effectively attenuated and hardly visible in output, Figure 7b. However, there was still some remaining receiver ghost energy in the data as can be highlighted in Figure 8, which shows the frequency spectra before (green) and after (red) the source designature. The ripples in the spectrum with a period of ~100 Hz before the deghosting (green arrow) were suppressed, but still visible in part of the spectrum between 400 and 600 Hz after deghosting (red arrow). The receiver notches were suppressed further when longer-offset data with notch diversity was added and were not visible in the final image.
In Figure 8 we also observe that the spectrum has been widened, and that the source ghost notch at ~1250 Hz has been partly filled.
Comparison of images from novel and conventional survey geometries
We have described the unique processing steps for the Novel dataset which were facilitated by a source-over-streamer acquisition geometry and a new sparker source.
For the Conventional survey, with its shallow streamer towed behind the source, we did not have access to the direct downgoing wavelet, so it was more difficult to correct for vertical source motion and the exact streamer location. Apart from that, we applied the same processing steps for both surveys;
• Denoising
• Source trigger time correction – using the electromagnetic event
• Source wave-motion correction – using the direct wave in the Novel survey and the water bottom reflection in the Conventional survey
• Source designature – using the direct vertical wave extracted from the Novel survey
• Receiver deghosting
• Velocity model estimation – Using RMO gathers and 1508 m/s in the water column
• Tidal correction
• Kirchhoff depth migration and angle stack up to 36o – Image bin size 0.5 m
The observant reader will notice that de-multiple was omitted from the workflow. The reason for this was that the water bottom multiples appeared deeper than the shallow 30-40 m depth beneath the seabed that we focus on here.
The final migrated images of the ~10 km profiles are shown in Figure 9 with zooms of the smooth pockmark-free water bottom in the south-eastern part of the profile. The key geological features, as described above, are indicated by red arrows in Figure 9a, while the improvements in imaging from Conventional to Novel are shown by green arrows in Figure 9b. The main improvements brought by the source-over-deep-streamer Novel
Figure 7 Common-channel (Channel 18) gather before (a) and after (b) source de-signature, source deghosting, spectral shaping and receiver deghosting.
Figure 8 Common-channel (Ch 18) gather before (green) and after (red) source de-signature, source deghosting, spectral shaping and receiver deghosting.
survey configuration were better focusing, a reduction in jitter noise caused by the choppy water, and lower noise levels due to the deep streamer. The lack of wave-motion correction in the Conventional survey led to a broken-up water bottom and subsurface geology all along the profile. This is clearly visible in the zooms in Figure 10, with the Novel image showing improved focusing and less noise.
Part of the explanation for this overall improvement is due to the fact that there was more wind and waves (~60 cm wave heights) on June 19 2024 when the Conventional survey was acquired while the Novel survey, acquired on 20 June, had calmer weather (~30 cm wave heights). However, the main reason was the correction of the source shifts due to wave motion in the Novel survey combined with the greater position-stability and quieter conditions of the streamer at the ~8 m depth.
Conclusions
The only differences between the Novel source-over-streamer acquisition and the Conventional source-in-front-of-streamer acquisition described in this paper was the depth of the streamer and the location of the source relative to the streamer. The challenge of deghosting the deep streamer data from the Novel survey was solved by an accurate cable depth estimation and adaptive ghost model subtraction. The advantages of the Novel acquisition were clearly visible in the imaging examples with improved focusing, less jitter and less noise. The sparker source, used in both surveys, created a source wavelet of short duration, uniform directionality and no notches in the spectrum which is a great advantage in the source designature. With the Novel acquisition it was possible to measure the direct uninterrupted downgoing wave from the sparker source, which
Figure 10 Zooms of the yellow rectangles from the Conventional and Novel surveys in Figure 9 with pockmarks, sedimentary layering and strong Eocene folding. The image improvement in the Novel survey is obvious.
Figure 9 Final images from Conventional (a) and Novel (b) survey configurations with geological features indicated by the red arrows in (a) and improvements in imaging by green arrows in (b). The zoom of the smooth water bottom in the upper right-hand corner of (a) and (b) shows the false ripples introduced in the Conventional survey that have been suppressed by the Novel survey. The zooms in the yellow rectangles are shown in Figure 10.
was used for source designature, correcting for source wave motion and streamer depth corrections. The Novel acquisition also contained zero-offset and split-spread data which improves the usable fold and reduces NMO stretching. The combination of the Novel acquisition and the meticulous processing led to a significant reduction in noise and more detailed mapping of the geological features in the area, such as faults and folding, biogenic gas pockets, and thin bedding. Furthermore, the Novel acquisition with its deep streamer will be more robust in adverse weather conditions than the Conventional survey with its shallow streamer, reducing the need for downtime for future source-over-spread UHR acquisitions.
Acknowledgements
We thank our colleague Matt Ledger in Viridien for continuous expert advice on 2D UHR processing and for providing the velocity model. We would also like to thank the wider team of experts from TotalEnergies and Kappa for providing continuous support throughout the duration of the project from August 2024 to January 2025: Mourad Chiali, Eric Cauquil, Aldo Cardonna, Erwan Larvor, Natacha Barbier, Loic Nedelec, Fabrice Perreau and Sebastien Delecraz. Finally, we thank Kappa, SIG, TotalEnergies and Viridien for giving us permission to publish this paper.
References
Camerer, A., Grubb, C. and Mandroux, F. [2018]. Expanding the limits of operational feasibility in marine seismic acquisition: deploying a source-over-spread solution. 80th EAGE Annual Conference & Exhibition, Extended Abstracts Davies, D., Allinson, C. and Higson, M. [2020]. Obtaining sub-metre vertical and spatial resolution from seismic data – the Clair experience. EAGE 2020 Annual Conference & Exhibition Online, Extended Abstracts. https://doi.org/10.3997/2214-4609.202010456.
Dusart, J., Tarits, P., Fabre, M., Marsset, B., Jouet, G., Erhold, A., Riboulot, V. and Baltzer, A. [2022]. Characterization of gas-bearing sediments in coastal environment using geophysical and geotechnical data. Near Surface Geophysics, 20, 478–493. https://doi.org/10.1002/ nsg.12230.
Flamme, J., Tarits, P., Fabre, M., Jouet, G., Ehrhold, A., Lepot, A. and Marsset, B. [2020]. Characterization of shallow gas in coastal environment using jointly marine ERT and UHR seismic imaging. NSG2020 4 th Applied Shallow Marine Geophysics Conference, Extended Abstracts . https://doi.org/10.3997/22144609.202020046.
Kluesner, J., Brothers, D., Hart, P., Miller, N. and Hatcher, G. [2018]. Practical approaches to maximizing the resolution of sparker seismic reflection data. Marine Geophysical Research, 40, 279–301. https://doi.org/10.1007/s11001-018-9367-2.
Lebedeva-Ivanova, N., Polteau, S., Bellwald, B., Planke, S., Berndt, C. and Stokke, H.H. [2018]. Toward one-meter resolution in 3D seismic. The Leading Edge, 37(11), 818–828, https://doi.org/10.1190/ tle37110818.1.
Poole, G. [2013]. Pre-migration receiver deghosting and redatuming for variable depth streamer data. 83rd Annual International Meeting, SEG, Expanded Abstracts, 4216-4220.
Provenzano, G., Henstock, T.J., Bull, J.M. and Bayrakci, G. [2020]. Attenuation of receiver ghosts in variable-depth streamer high-resolution seismic reflection data. Marine Geophysical Research, 41, article number 11. https://doi.org/10.1007/s11001-020-09407-9.
Telling, R., JafarGandomi, A. and Perratt, O. [2024]. Towards quantitative interpretation of UHR marine seismic: An example from the North Sea. 85th EAGE Annual Conference & Exhibition, Extended Abstracts. https://doi.org/10.3997/2214-4609.202410552.
Vinje, V., Lie, J.E., Danielsen, V., Dhelle, P.E., Siliqi, R., Nilsen, C.-I., Hicks, E. and Camerer, A. [2017]. Shooting over the seismic spread. First Break, 35(6). https://doi.org/10.3997/1365-2397.35.6.89461.
To serve the interests of our members and the wider multidisciplinary geoscience and engineering community, EAGE publishes a range of books and scientific journals in-house. Our extensive, professional marketing network is used to ensure publications get the attention they deserve.
EAGE is continually seeking submissions for both book publishing and articles for our journals.
A dedicated and qualified publishing team is available to support your publication at EAGE.
100+
80+
Timing the triggers: Radiocarbon
chronostratigraphy
for geohazard assessment in offshore Myanmar
Joy Muraszko1, Elena Grimoldi1, Riccardo Borella1, Andrea Caburlotto2 and Francesca Zolezzi1 present radiocarbon age data from eight Rakhine Basin cores, targeting turbidites and MTDs to support long-term geohazard evaluation.
Introduction
Submarine geohazards – like slope failures, turbidity currents, and debris flows – pose a serious threat to offshore infrastructure. Nowhere is this risk more pronounced than in the tectonically active and sediment-rich Rakhine Basin, offshore western Myanmar. Situated at the complex boundary zone between the Indian, Eurasian and Sunda plates, with the Burma microplate caught in between, the Rakhine Basin is a foredeep basin formed during oblique convergence since the Paleocene (Ma et al., 2020). This region is dynamic and tectonically active, with widespread faulting and deformation along the continental margin making it highly prone to slope instability. Myanmar regularly experiences significant earthquakes,
including the recent 2025 Mw 7.1 event that ruptured segments of the outer-arc thrust system, and the 2004 Sumatra-Andaman megathrust earthquake (Mw 9.1-9.3), which generated a devastating tsunami. In addition to seismic triggers, the region is fed by intense monsoonal systems and episodic tropical cyclones, and routinely subjected to strong seasonal hydrodynamic forcing, all of which can promote sediment remobilisation and slope failure. Critically, this region also hosts some of Myanmar’s most significant hydrocarbon developments, making the Rakhine Basin a high-stakes frontier for geohazard assessment and infrastructure planning.
Despite its significance, the sedimentary record of recent slope failures in the Rakhine Basin remains poorly constrained,
1 RINA Consulting | 2 Istituto Nazionale di Oceanografia e Geofisica Sprerimentale (OGS)
Figure 1 Location of study area and tectonic setting.
particularly in terms of timing and recurrence. To support geohazard risk assessment in a planned gas field development, 12 box and gravity cores were collected across the outer shelf to upper and mid-continental slope (-110 to -980 m water depth). Core locations were strategically selected based on multibeam bathymetry and seismic data interpretation, targeting key morphological and acoustic features to groundtruth the nature and timing of shallow mass transport deposits (MTDs). The seafloor here is incised by a network of erosional canyon complexes and channels that extend across the shelf break, with clear signs of retrogressive slope failure and buried debris flows.
This study presents the new radiocarbon dating results from eight of these cores, focusing on turbidites and MTDs. Building on previous geophysical interpretations and coring efforts in the region, this work contributes to a broader, longterm geohazard assessment framework developed through ongoing investigations by RINA Consulting. By establishing a time-calibrated record of recent sedimentary disturbances, we assess the recurrence and triggers of slope instability in the Rakhine Basin – and their direct implications for safe and sustainable offshore development.
Methods
A total of 16 sub-samples were selected from eight gravity cores for radiocarbon (14C) dating and biostratigraphic analysis. Subsampling targeted key intervals identified through sedimentological logging, multi-sensor core logging (MSCL), and X-ray radiography. These intervals included sharp basal contacts, laminated intervals, and organic-rich layers interpreted as potential turbidites or MTDs.
Biostratigraphic analysis was performed by Biochron (UK), while accelerator mass spectrometry (AMS) radiocarbon dating was conducted by Beta Analytic (Florida, USA). Radiocarbon ages were calibrated using the Marine20 calibration curve to obtain calendar-age estimates.
Sedimentation rates were estimated from depth-age models derived from the calibrated radiocarbon dates. These rates were used to assess the timing and to assess the timing and recurrence of depositional events and to infer temporal patterns in slope instability across the study area.
Turbidite event timing and characteristics
The clearest record of a discrete turbidity current deposit was identified in core GC#12, where a sharp basal contact, laminated
Figure 2 Bathymetry of study area with coring locations and examples of encountered geohazards.
silty interval, and a gradual transition to hemipelagic mud was found at 1.2 m below seafloor. This feature was dated at approximately 2694 cal yrs BP, confirming its interpretation as a discrete event deposit.
Comparable features were observed in cores GC#09 and GC#05A, both exhibiting similar laminated silty layers with radiocarbon dates of approximately 6238 cal yrs BP and 6878 cal yrs BP, respectively. These deposits reflect episodic activity of turbidity currents, potentially triggered by either seismic events or monsoon-driven hyperpycnal flows.
The grain size analyses of these turbidites revealed clayey-silty textures, with up to 25% sand fraction in some intervals. These characteristics suggest moderate energy flows with mixed sediment sources, likely linked to shelfal erosion during periods of heightened fluvial discharge.
Buried mass transport features
Core GC#07A was positioned to investigate a distal debris flow lobe interpreted from AUV bathymetry and seismic data, where internal chaotic reflectors suggest a stacked mass transport deposit complex. However, the core recovered a homogenous sequence of hemipelagic mud with only faint lamination and no sedimentary structures indicative of recent remobilisation.
A radiocarbon age of 5767 years BP at 0.8 mbsf indicates that any associated mass transport activity predates this horizon. The overlying uninterrupted fine-grained sedimentation suggests a prolonged period of slope stability, with no evidence of subsequent reactivation. While the seismic data provide evidence of mass-wasting history at this location, and the depositional lobes are prominent in the bathymetry, the absence of recent deposits or deformation in the core reclassifies this feature as a buried paleo-hazard. Its burial and preservation beneath stable Holocene sediments highlight a broader transition from episodic slope failure to sustained hemipelagic deposition under present-day environmental conditions.
Sedimentation rates and regional inactivity
Sedimentation rates across the study area average ~18.3 cm/yr for the Holocene, but show significant spatial variability, with values ranging from ~3.8 to nearly 50 cm/kyr. This variability reflects differences in slope position, channel proximity, and possibly local hydrodynamic regimes. Elevated sedimentation rates (e.g. ~49.8 cm/kyr at GC#12 and ~21–25 cm/kyr at GC#05A and GC#09) are associated with cores located closer to canyon heads or incised slope gullies in the upper-mid slope region. These sites are likely influenced by focused sediment delivery. In contrast, lower sedimentation rates (<5 cm/kyr at GC#01 and GC#02A) occur at deeper or more distal locations on the slope, including regions interpreted as contourite-influenced settings, reflecting a transition to background hemipelagic sedimentation in areas removed from direct sediment bypass or depositional focusing. This pattern is consistent with regional-scale Holocene trends in the Bay of Bengal, where sediment supply to the deep ocean has declined under sea-level highstand and reduced monsoon intensity (Liu et al., 2023).
The lack of modern turbidites or mass transport deposits in the upper stratigraphy suggests that turbidity currents have become increasingly rare during the Holocene. Ground-truthing with geohazard cores consistently showed an uninterrupted hemipelagic drape, formed primarily by the slow settling of fine particles in a low-energy environment. This aligns with regional sea-level highstand conditions and a decline in fluvial input, as modern rivers no longer deliver sufficient sediment to initiate density flows. The sustained hemipelagic sedimentation implies that slope instability has been minimal for several thousand years, allowing for the progressive burial and preservation of older features. These observations further support the interpretation that the continental margin has shifted from a regime dominated by episodic sediment remobilisation to one of passive accumulation. In this context, features flagged as geohazards based on bathymetry or seismic interpretation — such as canyon-linked MTDs and
Figure 3 Turbidites encountered in the study area in X-ray and photographs, in cores a) GC#12 (2.18-2.38 mbsf,
older than ~6,010 cal yrs BP) and c) GC#05A
erosional scarps — are more accurately interpreted as relics of a more dynamic palaeoenvironment, now largely inactive under present-day conditions.
Correlation and interpretation of findings
Sedimentological, chronological and geophysical data were synthesised with legacy survey results to reconstruct the recent geohazard history of the slope. By correlating stratigraphy across the study area, the aim is to trace past geohazard event horizons where possible, deciphering their likely triggers and establishing a temporal framework for sediment remobilisation processes shaping the seabed today.
Four main sedimentary facies were identified: hemipelagites, turbidites, contourites, and MTDs. The overwhelming dominance of hemipelagic mud reflects a widespread, continuous drape of fine-grained sediments across the slope, with no evidence of erosional truncation or event layers in the upper stratigraphy. This drape, between 40 and 190 cm thick, shows no signs of interruption and is consistent with long-term calm depositional conditions that have persisted in the study area throughout the last few thousand years.
Turbidite deposits are characterised by laminated, organic-rich, silty layers with sharp basal contacts and fining-upward sequences. They mostly seem to correspond to what can be called hyperpycnal events, likely triggered by monsoon associated anomalously high rainfall and resulting run-off, directly causing
the plunging of suspended sediment plumes downslope. The most recent event which can be tentatively traced across the basin occurred between 2694 and 1145 years BP, with other turbidite events dating to ~10-12,000 years BP, suggesting a waning frequency of events through the Holocene. The limited number and isolated nature of these events suggest infrequent triggering under specific boundary conditions, rather than persistent instability.
Debris flows were sparsely identified in the stratigraphy, and were generally thin, fine-grained, and deeply buried. Slumps are generally localised, sourced from nearby ridge flanks, with limited run-out and no recurrence observed in the upper stratigraphy. The findings support the interpretation that most MTDs in the area are paleo-hazards, reflecting slope failure episodes that occurred more than 6000-13,000 years ago.
Fault rate displacement was also assessed. Cores GC#01 and #02A, collected on opposing sides of a seabed-reaching normal fault, were used to constrain its movement rate through correlation of dated sedimentary horizons. The estimated slip rate of 0.04–0.05 mm/yr confirms these are slow-moving, likely gravity-driven faults linked to retrogressive slope processes rather than active tectonic boundaries.
Discussion
Integrated sedimentological and chronological analysis shows that slope failure and turbidity activity in the study area were episodic and largely restricted to the Late Pleistocene and early Holocene.
Figure 3 Correlations of turbidites and mass transport deposits across the study area.
These events are represented by distinct turbidite and mass transport deposits, most of which predate 10,000 years BP. Between these discrete events, intervals of hemipelagic sedimentation dominate, indicating relatively quiescent background conditions.
The occurrence of these mass-wasting events likely reflects the interplay of several regional forcing mechanisms. Deglacial sea-level rise, intense monsoonal runoff, and seismicity associated with nearby tectonic structures, such as the Sunda megathrust and Sagaing Fault, are all probable contributors. The timing of dated deposits – particularly those from core GC#12 – may correspond to climatically or tectonically active phases, including episodes of monsoon intensification or increased seismic frequency during glacio-eustatic transitions.
The absence of recent turbidite and MTD events in the upper stratigraphy suggests a long-term transition to a more stable depositional environment during the mid-to-late Holocene. This may reflect reduced sediment supply, rising sea levels, or changes in sediment routing from onshore catchment. Similar trends of postglacial stability have been documented elsewhere in the Bay of Bengal and Andaman Sea (Weber et al., 1997; Achyuthan et al., 2014). The burial and preservation of older debris flow features without evidence of reworking further indicates that some seafloor features previously considered hazardous are now geologically inactive.
Conclusions
This study provides a time-calibrated snapshot of geohazard evolution in the Rakhine Basin, revealing a slope system that has transitioned from a periodically dynamic, event-driven sedimentary system to a relatively stable area over the past 6000 years. By integrating geophysical data interpretation, sedimentological logging and radiocarbon dating, we developed a chronostratigraphic framework to assess the recurrence and timing of geohazard triggers relevant to offshore development.
The sedimentary record is dominated by hemipelagic facies, with average sedimentation rates of ~20 cm/kyr on the upper-tomid slope, indicating stable environmental conditions during the Holocene. In deeper slope settings, reduced sedimentation rates (~4 cm/kyr) suggest enhanced bottom current activity.
Turbiditic sequences are characterised by thin, silty, and organically enriched layers, interpreted as hyperpycnal flows triggered by monsoon-driven runoff. However, these deposits are notably absent in the upper stratigraphy, indicating that no such events have occurred over the past 6000 years. This cessation is consistent with post-glacial sea-level rise, a northward shift and weakening of the Indian summer monsoon, and a broader regional drying (Rashid et al., 2011). Such climatic changes led to significantly decreased erosion and riverine sediment supply. MTDs identified in the study area are limited and localised, exemplified by small slumps such as in core GC#10. These
deposits reflect minor slope instability with negligible effects on the broader seabed morphology. Larger-scale MTDs, while present as buried features (e.g., debris-flow lobes targeted by core GC#07A), show significant burial beneath stable sediments, underscoring their classification as paleo-hazards with limited relevance to modern conditions.
Overall, the geological record supports an interpretation of long-term slope stability during the late Holocene, with minimal recent sedimentary disturbance. Radiocarbon-supported facies analysis thus remains an essential approach for distinguishing historical from active geohazard threats, providing critical context for infrastructure planning and risk mitigation in offshore environments.
Acknowledgements
This work was funded by POSCO International and conducted by RINA Consulting. Radiocarbon analysis was performed by Beta Analytic (USA), and biostratigraphic interpretation was provided by Biochron (UK). Geophysical surveys were supported by Fugro. Special thanks goes to OGS Trieste for laboratory facilities and technical support.
References
Achyuthan, H., Nagasundaram, M., Gourlan, A.T., Eastoe, C., Ahmad, S.M. and Padmakumari, V.M. [2014]. Mid-Holocene Indian Summer Monsoon variability off the Andaman Islands, Bay of Bengal. Quaternary International, 349, 232–244. https://doi.org/10.1016/j. quaint.2014.07.041.
Curray, J.R., Emmel, F.J. and Moore, D.G. [2002]. The Bengal Fan: morphology, geometry, stratigraphy, history and processes. Marine and Petroleum Geology, 19(10), 1191-1223. https://doi.org/10.1016/ S0264-8172(03)00035-7.
Liu, S., Ye, W., Zhang, H., Cao, P., Li, J., Sun, X., Li, X., Fang, X., Khokiattiwong, S., Kornkanitnan, N. and Shi, X. [2023]. Sediment provenances shift driven by sea level and Indian monsoon in the southern Bay of Bengal since the last glacial maximum. Frontiers in Marine Science, 10, 1106663. https://doi.org/10.3389/fmars.2023.1106663.
Ma, H.X., Fan, G.Z., Shao, D.L., Ding, L.B., Sun, H., Zhang, Y., Zhang, Y.G. and Cronin, B.T. [2020]. Deep-water depositional architecture and sedimentary evolution in the Rakhine Basin, northeast Bay of Bengal. Petroleum Science, 17(3), 598-614. https://doi.org/10.1007/ s12182-020-00442-0.
Rashid, H., England, E., Thompson, L. and Polyak, L. [2011]. Late glacial to Holocene Indian summer monsoon variability based upon sediment records taken from the Bay of Bengal. Terrestrial, Atmospheric and Oceanic Sciences, 22(2), 215-228.
Weber, M.E., Kudrass, H.R., Hübscher, C., Erlenkeuser, H. and Michaelis, D. [1997]. Active growth of the Bengal Fan during sea-level rise and highstand. Geology, 25(4), 315-318. https://doi.org/10.1130/009 1-7613(1997)025<0315:AGOTBF>2.3.CO;2.
KEEPING THE EUROPEAN SUBSURFACE ENERGY COMMUNITY CONNECTED
Seventh EAGE Rock Physics Workshop
Register for the Seventh EAGE Rock Physics Workshop before 2 October to enjoy the early bird rate, which includes full access to both the workshop and field trip! Plus, we’re excited to offer a 50% discount on registration fees for African residents — don’t miss this opportunity to connect, explore, and learn at a great value! 10-12 NOVEMBER 2025 • CAPE TOWN, SOUTH AFRICA
Early bird Deadline: 2 October 2025
Global inversion of ERT and IP data using VFSA for improved detection and uncertainty assessment of leachate accumulation in urban landfills
Giorgio De Donno1*, Michele Cercato1 and Davide Melegari1 present an application of a global inversion approach based on the Very Fast Simulated Annealing (VFSA) algorithm to ERT and IP datasets acquired on a municipal solid waste (MSW) landfill located in Central Italy.
Abstract
Electrical Resistivity Tomography (ERT) and induced polarisation (IP) methods are widely employed in the characterisation of urban landfills due to their sensitivity to subsurface moisture and electrochemical properties of waste. Traditional local inversion techniques, typically based on smoothness-constrained Occamtype methods, can fail to resolve the high spatial variability of leachate accumulation areas. Additionally, these techniques do not provide an assessment of the uncertainty associated with the detection of accumulation areas, which is pivotal for informing quantitatively the landfill management. In this study, we apply a global inversion approach based on the Very Fast Simulated Annealing (VFSA) algorithm to ERT and IP datasets acquired on a municipal solid waste (MSW) landfill located in Central Italy. This site, characterised by a steep slope and high risk of leachate-induced instability, is currently monitored with time along multiple profiles. The global inversion process was implemented on a selected line where also piezometric level logged in wells are available. Posterior model ensembles were also analysed to derive uncertainty estimates, and petrophysical transformations were applied to extract water content and Cation Exchange Capacity (CEC) from the geoelectrical parameters. The results demonstrate the effectiveness of the VFSA method in detecting highly variable leachate zones, as confirmed by the good agreement with leachate levels logged in wells. The uncertainty assessment highlighting areas of higher and lower reliability of the geophysical model can further support the landfill monitoring, with implications for risk assessment and long-term management.
Introduction
Urban waste landfills present complex, dynamic subsurface environments characterised by heterogeneity in both composition and hydro-chemical conditions. Among the key concerns in landfill management is the formation and accumulation of leachate, a liquid produced by the percolation of water through solid waste (Mukherjee et al., 2015). A leachate flow outside the landfill site may cause serious environmental issues to groundwater, while in the case of landfills located on slopes leachate accumulation can
also trigger instability. Therefore, in the latter case, detecting and monitoring the accumulation zones is critical not only for environmental protection but also for geotechnical risk mitigation.
Geophysical methods have proven effective in supporting non-invasive characterisation of Municipal Solid Waste (MSW) landfills. Electrical Resistivity Tomography (ERT) and induced polarisation (IP) techniques have been extensively applied due to their sensitivity to changes in moisture content, salinity, and electrochemical properties of the waste mass (see De Donno et al., 2024 for a review). ERT provides information on the bulk resistivity of the subsurface, which mainly correlates with saturation levels and waste composition, while the IP effect is primarily caused by microbial activity in the waste mass (e.g. Flores-Orozco et al., 2020). These attributes make ERT and IP complementary tools in the identification of zones saturated by leachate.
Conventionally, inversion of geoelectrical data has been conducted using local and deterministic approaches employing Occam’s-like smoothness-constrained inversion algorithms (de Groot-Hedlin and Constable, 1990). While computationally efficient, such methods may obscure sharp boundaries or localised anomalies such as leachate pockets, as well as the solution may remain trapped in local minima. Additionally, they fail to provide a statistical assessment of uncertainty associated with the inverted models, which can be of paramount importance in heterogeneous media such as landfills.
In contrast, global inversion techniques, exploring the entire model space offer a promising alternative, even though they require a higher computational effort. Among the global inversion algorithm, the Very Fast Simulated Annealing (VFSA) algorithm (Ingber, 1989) has gained attention due to its capability to navigate high-dimensional and non-linear inverse problems (e.g. Cercato, 2011). Unlike Monte-Carlo or genetic algorithms, VFSA is a cost-effective algorithm, balancing the capability to properly sample the whole model space and the speed of convergence (Sen and Stoffa, 2013). Despite its potential, VFSA and other global inversion methods have had limited practical application in ERT/IP data inversion due to the high computational demand
required by the ERT/IP forward solver and the large number of evaluations needed to achieve convergence. However, recent works have begun to incorporate probabilistic frameworks and ensemble analysis to assess model uncertainty, further enhancing the interpretative power of global inversion schemes (e.g. Aleardi et al., 2021; Isunza Manrique et al., 2023).
This study builds on these developments by applying a global VFSA-based inversion algorithm to jointly invert ERT and IP data acquired on a MSW landfill located in Central Italy. The site, situated on a steep slope, is subject to potential leachate-induced instability, making accurate and reliable detection of leachate pockets a priority for both environmental monitoring and structural safety. The survey targeted a specific area within the landfill known from previous local inversions to exhibit high variability in moisture conditions (De Donno et al., 2025).
Our implementation leverages an extended version of the VEMI inversion software (De Donno and Cardarelli, 2017), customised to perform forward modelling of resistivity and integral chargeability using the finite-element method on structured meshes. The global inversion, carried out using VFSA, enables both resistivity and chargeability model ensembles to be generated. These models are then post-processed to derive petrophysical properties, such as volumetric water content and cation exchange capacity (CEC), using empirical relationships established by Revil et al. (2020) and site-specific calibration data, including leachate levels and conductivity logged in wells. Then, the quantification of model uncertainty and correlation is addressed through a statistical analysis of the model ensembles. By computing posterior covariance and correlation matrices, we assess the spatial variability of confidence in the inversion results, which informs both the reliability of interpretations and future monitoring strategies.
The goal of this paper is threefold:
• To demonstrate the applicability and advantages of VFSAbased global inversion in resolving complex resistivity and IP patterns associated with leachate accumulation in a real landfill environment;
• To provide petrophysical interpretations of the inverted models through derived water content and CEC, offering insights into waste moisture and composition;
• To evaluate the uncertainty and reliability of the inversion results using statistical descriptors from the ensemble of accepted models.
Methods
Study area and data acquisition
The study was conducted at a large municipal solid waste landfill located in Central Italy (Figure 1), situated on a steep natural slope, where the risk of leachate accumulation triggering slope instability is a major concern. The site has been active for several years, and the waste mass composition reflects a wide range of waste types and degradation stages. The landfill stratigraphy can be summarised as a three-layer model: i) a top thin cover of compacted soil, ii) the heterogeneous waste mass with variable leachate saturation levels, and iii) a bottom high-density polyethylene (HDPE) liner, acting as an insulator due to its very high resistivity (> 107 Ωm). Since leachate accu-
mulation zones are expected to be highly variable within the waste mass, a high-resolution geophysical survey is essential for their detection.
To this aim, four ERT/IP profiles (L1–L4) were acquired across the landfill (see Figure 1 for location), using a SyscalPro48 multi-channel resistivity-meter (IRIS Instruments), equipped with 48 stainless steel electrodes spaced 5 m apart, using a dipole-dipole array configuration in a roll-along mode. The current injection cycle was performed using a pulse duration of 2 s with 2 stacks (50% duty cycle), while the IP decay curve was sampled with 20 logarithmically spaced gates (first gated centred at 30 ms, last at 1.78 s), with a delay time of 20 ms after the current switch-off. Apparent resistivity (ρₐ) and integral chargeability (mₐ) were then derived from the recorded voltage data, removing poor-quality readings (negative data/decay curves, data with experimental standard deviations higher than 10%).
Firstly, the acquired dataset was locally inverted only for resistivity, to have a preliminary screening of the landfill to select the most suitable line for global inversion. The resistivity models (Figure 2) clearly show a main accumulation zone (conductive intermediate layer), located in the natural impluvium of the landfill (old topographic surface), which can contribute to the slope instability. Conversely, the resistive zones are related to the unsaturated waste and covering soil (top layer) and to the presence of the HDPE liner (bottom layer), acting as an insulator.
Figure 1 Aerial image of the urban waste landfill in Central Italy, with the location of the four investigated ERT/IP lines. The segment of L2 selected for global inversion is marked with a dotted black line and the piezometers (P1-P2) with blue circles (after De Donno et al., 2025, modified).
Figure 2 Three-dimensional reconstruction of the resistivity of the four profiles (L1_ L4), where the preferential leachate pathway is marked with a dashed black arrow.
However, these results leave room for ambiguous interpretation of the leachate-saturated zones, as the definition of a resistivity threshold for delineating fully saturated areas is not straightforward. Conversely, an accurate assessment of the fully saturated zones is pivotal to ensure that the drainage interventions will be effective for landfill management (Mukherjee et al., 2015). We selected the final part of the L2 profile (20 electrodes starting from x = 205 m, dotted black line in Figure 1) for applying global inversion to the combined ERT/ IP dataset, with the aim of improving resolution in detection of leachate accumulation areas, providing petrophysical models and evaluating the uncertainty and reliability of the inversion results. The choice of L2 is also motivated by the availability of two piezometers (P1 and P2 in Figure 1), installed for logging leachate levels and conductivity, which were later used for petrophysical calibration. To speed up the global inversion process, we downgraded the electrode spacing to 10 m as well as the mesh size in the profile direction, which was fixed to be equal to the electrode spacing.
Global inversion algorithm
Our global inversion approach is based on the Very Fast Simulated Annealing (VFSA) algorithm (Ingber, 1989), due to its robustness and its use of a small number of inversion parameters. The VFSA algorithm draws random models from a Cauchylike distribution, which is dependent on temperature. Models that lower the energy are always accepted, while models that increase energy are accepted with a probability that is finite and temperature-dependent (Sen and Stoffa, 2013). This acceptance criterion, coupled with an adequate cooling schedule and an adequate number of random samples, ensures that the inversion process converges to the global minimum of the energy function, making it virtually independent of the initial model (Cercato, 2011). In this study, the energy function E is defined, for the model of resistivity (ρ) and chargeability (m) under consideration, as:
(1)
being the dataset with and apparent resistivity and chargeability vectors and N the number of measurements (doubling the number of quadrupoles). A log-10 conversion of parameters was used because it is better suited for electrical data, usually spanning several orders of magnitude (Kim and Kim, 2011).
To improve the stability of the solution, after each simulation step, the randomly altered resistivity values are smoothed using a 5-point cross-median filter and the random search is constrained within closed resistivity and chargeability intervals ([0.2-105 Ωm] and [1-500 mV/V]), reflecting the expected ranges of parameters in urban landfills. After a preliminary trial-and-error stage, where we explored different temperature ranges, we set the initial and final temperature values to 1 and 10-9, while the total number of random walks is set to 2·106. Since one run of the VFSA algorithm is often not enough to find the global solution (Sen and Stoffa, 2013), we performed 10 independent runs using parallel calculations (10 cores/20 threads CPU).
Petrophysical transformation and uncertainty analysis
To derive petrophysical parameters after inversion, we convert the resistivity and chargeability minimum misfit models into water content (θ) and cation exchange capacity (CEC) models, using the equations after Revil et al. (2020). We assumed the cementation exponent in the Archie’s equation equal to 2, the waste grain density equal to 1500 kg/m3 (Steiner et al. 2022) with a leachate conductivity of 1300 mS/m as directly measured in the wells. The resulting θ and CEC models allowed for hydro-geophysical interpretation of the subsurface, offering insights into waste saturation patterns and degradation zones with high biological or electrochemical activity.
Uncertainty on model parameters is estimated via the posterior covariance matrix:
where NM is the number of accepted models lying within a one-standard deviation threshold (68.2%) and is the mean model. The square root of the diagonal elements of C are the standard deviations (σ ρ and σ m). Then the a posteriori correlation matrix, which indicates the inter-dependence between the parameters, can be calculated:
where Cij is a generic element (i-th row and j-th column) of the covariance matrix C defined in equation (2).
Results
Inverted models
The results of the global inversion using the VFSA algorithm are presented in Figures 3 (models) and 4 (uncertainty analysis), as linearised 2D profiles. The impact of the linearisation of curvilinear acquisition on the geophysical model is marginal almost everywhere, and we can use the linearisation of the profiles in the inversion procedure (De Donno et al., 2025). The interpretation of the models is supported by independent well measurements (piezometers P1 and P2), which serve as ground truth for leachate level validation.
The results are shown in Figure 3 in terms of observed data (Figures 3a,b), mean (Figures 3c,e) and minimum misfit (Figures 3d,f) models, water content and CEC sections (Figures 3g,h), where the position of the bottom liner acting as an insulator (solid black line) and the well levels (white-filled area) are superposed Figures 3a and 3b display the input apparent resistivity and chargeability datasets, while Figures 3c–3f illustrate the resulting models after VFSA inversion, where Figures 3c and 3e present the mean models derived from all accepted models of the 10 runs, and Figures 3d and 3f the minimum misfit models, considered the best-fitting realisations. In both resistivity and chargeability sections, we detected three different layers:
• Top layer (from surface to 8-10 m), displaying high resistivity values (> 10 Ωm) and low chargeability (< 10 mV/V). This layer probably represents the compacted soil cover and the unsaturated waste, with limited moisture content and minimal leachate presence;
Figure 3 Results of VFSA inversion: (a) apparent resistivity and (b) chargeability datasets; mean and minimum misfit models of resistivity (c,d) and integral chargeability (e,f), water content (g) and CEC (h)cross-sections. The position of the bottom liner is marked with a solid black line and the leachate accumulations in wells with a white-filled area (black-filled areas indicate dry zones).
• Intermediate layer (10–30 m depth), exhibiting low resistivity (<10 Ωm) and moderate to high chargeability values (>10 mV/V) due to the partially/fully saturated waste mass. The inversion reveals significant lateral variability, with zones of very low resistivity interpreted as leachate-rich pockets, while the high chargeability areas are mainly a proxy for an increase of biogeochemical activity in the waste mass (Flores-Orozco et al., 2020);
• Bottom layer (>35-40 m depth), marked by a sharp increase in resistivity and a drop in chargeability due to the HDPE liner, which acts as an insulator. The location of this interface is also confirmed from the available data of the original landfill design (solid black line in Figures 3 and 4).
The close agreement between the well-observed leachate levels (white-filled zones) and the anomalies on the inverted models validates the physical interpretation and confirms the reliability of the global inversion framework.
Petrophysical parameters and uncertainty analysis
Figures 3g and 3h present the models of volumetric water content (θ) and cation exchange capacity (CEC), respectively. The water content model (Figure 3g) reveals high-saturation areas between 80 and 180 m along the profile and at a depth between 15 and
35 m, where θ exceeds 30-40%. These areas correlate well with the leachate levels recorded in wells P2, while the low leachate levels in P1 (almost dry) are in good agreement with the respective lower water content. The CEC model (Figure 3h) shows high values (above 100 meq/100g) between 100 and 130 m along the profile, likely to correlate with organic-rich waste and high microbial activity, while intermediate values (20-100 meq/100g) are retrieved in the remaining waste mass. In contrast, the upper and lower layers exhibit uniformly low CEC values (<20 meq/100g), consistent with the presence of covering and bottom layers, respectively.
Additionally, the inversion reliability is shown for both models in Figure 4 in terms of standard deviation (Figures 4a-4b) and correlation (Figure 4c) values, as well as by the misfit progress with iterations (Figure 4d).
High uncertainties are noted at the lateral and bottom zones of the resistivity profile, as expected due to the combined effect of the low sensitivity and high mean resistivity values. In contrast, the middle portion of the model shows low standard deviations, particularly around the P2 piezometer. The correlation matrix (Figure 4c) shows mostly weak off-diagonal correlations, with few localised clusters of positive correlation and a clear correlation observed in the filter-applied regions. These correlations are a product of the median filter used for stabilisation purposes and
indicate minor trade-offs between neighbouring cells. Finally, we clearly see in Figure 4d that all runs converge toward a similar minimum misfit value, demonstrating the repeatability and robustness of the global inversion algorithm. This behaviour also confirms that the global minimum is reliably identified despite the non-linear and non-unique nature of the problem.
Practical implications and conclusions
From a practical perspective, the results of this study offer two main benefits for landfill operators and environmental authorities, such as:
• An improved localisation of leachate hotspots (including the associated uncertainty);
• Informing quantitively drainage design, pumping strategy and/ or new installation of monitoring wells;
• Supporting the geotechnical risk assessment, particularly in landfills located on slopes, where leachate saturation may impact slope stability.
These advantages align with broader goals in sustainable landfill management, including compliance with environmental regulations, minimisation of long-term risks, and optimisation of post-closure monitoring.
From a more geophysical point of view, this study demonstrates the application and effectiveness of a global inversion approach — based on the Very Fast Simulated Annealing (VFSA) algorithm — applied to ERT and IP datasets in the context of leachate detection within a MSW landfill. Compared to conventional local methods, the VFSA-based strategy allows for enhanced model exploration and quantitative uncertainty assessment (Sen and Stoffa, 2013). In fact, variations in waste composition, compaction, permeability, and degradation processes lead to small and localised zones of
accumulation that may not be captured by traditional smoothness-constrained inversions. Therefore, a global inversion approach is well-suited to account for such complexity, offering a means to delineate these zones with associated confidence estimates.
Although the low resistivity values can be directly interpreted as a proxy for leachate accumulations, the integral chargeability is expected to decrease proportionally to the increase of saturation, due to the increase of fluid and surface conductivity, thus yielding lower IP responses (Flores-Orozco et al., 2020). Conversely, high chargeability anomalies are mainly due to biogeochemically active zones (high organic matter), which is responsible for high rates of microbial activity, resulting in high polarisation that surpasses the high salinity and conductivity (De Donno et al., 2025). Therefore, we overcome this residual ambiguity in interpreting the geophysical models by using well-established petrophysical relationships, which are given in this case in terms of integral chargeability (Revil et al., 2020), though alternative formulations are available also for spectral (i.e. Cole-Cole) parameters (e.g. Weller at al., 2013). The two distinct anomalies corresponding with high water content (Figure 3g) and high CEC values (Figure 3h), confirm that high saturation and significant biologically active conditions pertain to two separated areas in the waste mass. The agreement between the inverted models and the leachate levels logged in piezometers provides strong validation for this method, particularly in complex landfill environments where physical heterogeneity and chemical gradients are pronounced. However, the current approach relies only on empirical petrophysical relationships to derive water content and CEC, while calibration of petrophysical parameters (i.e. cementation exponent, waste density) with laboratory data could improve their reliability.
Finally, the convergence behaviour observed across all ten runs confirms the reproducibility and robustness of the global
Figure 4 Uncertainty assessment: standard deviation cross-section for resistivity (a) and chargeability (b) models, correlation matrix (c) and error progress with iterations (d). The position of the bottom liner is marked with a solid black line and the leachate accumulations in wells with a white-filled area (black-filled areas indicate dry zones).
inversion strategy. Furthermore, the model covariance and correlation analyses offer valuable insights into parameter trade-offs and spatial resolution, which are rarely available in local inversion schemes. Despite these strengths, computational demand remains significant, particularly using high-resolution meshes and/or multi-parameter datasets. Although parallelisation of the multiple runs helped us to drastically reduce the computation effort, future developments could benefit from GPU acceleration or adaptive mesh refinement to optimise performance.
References
Aleardi, M., Vinciguerra, A. and Hojat, A. [2021]. A geostatistical Markov chain Monte Carlo inversion algorithm for electrical resistivity tomography. Near Surface Geophysics, 19(1), 7-26.
Cercato, M. [2011]. Global surface wave inversion with model constraints. Geophysical Prospecting, 59, 210–226.
De Donno, G., Melegari, D., Paoletti, V. and Piegari, E. [2025]. An integrated study of hard and soft cluster analyses for detecting leachate in a MSW landfill site using geoelectrical data. Waste Management, 195, 22-31.
De Donno, G. and Cardarelli, E. [2017]. VEMI: a flexible interface for 3D tomographic inversion of time-and frequency-domain electrical data in EIDORS. Near Surface Geophysics, 15(1), 43-58.
De Donno, G., Melegari, D., Paoletti, V. and Piegari, E. [2024]. Electrical and Electromagnetic Prospecting for the Characterization of Municipal Waste Landfills: A Review. In: Technical Landfills and Waste Management: Volume 1: Landfill Impacts, Characterization and Valorisation, 1-29.
de Groot-Hedlin, C. and Constable, S. [1990]. Occam’s inversion to generate smooth, two-dimensional models from magnetotelluric data. Geophysics, 55(12), 1613-1624.
Flores-Orozco, A., Gallistl, J., Steiner, M., Brandstätter, C. and Fellner, J. [2020]. Mapping biogeochemically active zones in landfills with induced polarization imaging: The Heferlbach landfill. Waste Management, 107, 121-132.
Ingber, L. [1989]. Very fast simulated re-annealing. Mathematical and Computer Modelling, 12(8), 967-973.
Isunza Manrique, I., Caterina, D., Nguyen, F. and Hermans, T. [2023]. Quantitative interpretation of geoelectric inverted data with a robust probabilistic approach. Geophysics, 88(3), B73-B88.
Kim, H.J. and Kim, Y. [2011]. A unified transformation function for lower and upper bounding constraints on model parameters in electrical and electromagnetic inversion. Journal of Geophysics and Engineering, 8(1), 21-26.
Mukherjee, S., Mukhopadhyay, S., Hashim, M.A. and Sen Gupta, B. [2015]. Contemporary environmental issues of landfill leachate: assessment and remedies. Critical reviews in environmental science and technology, 45(5), 472-590.
Revil, A., Ahmed, A.S., Coperey, A., Ravanel, L., Sharma, R. and Panwar, N. [2020]. Induced polarization as a tool to characterize shallow landslides. Journal of Hydrology, 589, 125369.
Sen, M.K. and Stoffa, P.L. [2013]. Global optimization methods in geophysical inversion. Cambridge University Press, UK.
Steiner, M., Katona, T., Fellner, J. and Flores-Orozco, A. [2022]. Quantitative water content estimation in landfills through joint inversion of seismic refraction and electrical resistivity data considering surface conduction. Waste Management, 149, 21-32.
Weller, A., Slater, L. and Nordsiek, S. [2013]. On the relationship between induced polarization and surface conductivity: Implications for petrophysical interpretation of electrical measurements. Geophysics, 78(5), D315-D325.
An exploratory geophysical study focused on a site of a wind energy generation park
Ana Abreu1*, Nicolás Valverde1, Valentina Curutchet1, Misael Lemes1, Santiago Delgado1, Freddy Rondon2 and Javier Sánchez-Rojas2 present the experimental procedure used to estimate the fundamental period of the soil, Tsoil, which is based on the horizontal-to-vertical spectral ratio (HVSR) method, and the fundamental period of the wind tower, Ttower, based on the top-to-base horizontal spectral ratio (HHSR) method.
Abstract
Uruguay’s commitment to incorporating non-traditional indigenous renewable energy sources into the national energy matrix represented a fundamental step towards energy independence. The country successfully transitioned from having no wind energy in its electrical distribution system to currently ranking among the world leaders in terms of wind power participation in its energy matrix. This study presents a survey campaign conducted at a productive wind farm site and on a wind tower structure using the horizontal-to-vertical spectral ratio (HVSR) method, multichannel analysis of surface waves (MASW), and seismic refraction tomography. Seismic velocities and ground accelerations were measured over a long period of time, obtaining environmental vibration records collected at various points on the structure and in the surrounding subsoil. The HVSR of microtremors recordings was used to extract relevant information from the data such as the natural vibration frequencies of the structure and underlying ground. The shear and compressional seismic wave velocities were calculated. These results may have applications in the correct site selection for future wind farms, in the design of wind turbine structures, as well as in monitoring and determining the structural health of existing wind towers.
Introduction
Uruguay’s energy policy led to a very rapid structural transformation of the energy matrix, and introduced electricity generation from alternative sources (mainly wind, solar and biomass) in high proportion. Currently, approximately 99% of the electricity generation comes from renewable energy sources. It is not surprising that in a recent report by the Renewable Energy Policy Network for the 21st Century (REN21) (2025) the country was ranked first globally, becoming a regional leader in clean energy. In addition, Uruguay has conducted tenders to create favorable conditions for investors (Uruguay XXI, 2022). Given the country’s vulnerability to the effects of climate change, it is necessary to increase its adaptive and resilience capacity, and this is included in the ECLP (Estrategia Climática de Largo Plazo) as one of the document’s core sections coordinated by the Ministry of Environment (2021).
Within the current scenario of growing demand for renewable energy – specifically the construction of wind turbine structures –there is a need to analyse the risks that may affect these types of structures. It is therefore necessary to assess risks both for design purposes and to represent different scenarios of events that could put a wind turbine support structure at risk. As noted by Martín del Campo (2020) most of the standards currently in force include wind turbine support structures in their seismic design chapters, and some also include information on wind design. However, there are few analytical studies on the simultaneous action of wind and earthquakes under different intensity levels. Wind turbine design has advanced significantly in terms of size and variety of structural shapes. As is often the case for structures, the design of wind towers is generally based on a fixed-base structural model, ignoring soil-structure interaction and the dynamic effects that this interaction causes, even on soft soils (Hau, 2006).
Onshore wind turbines can pose a high risk, especially if they operate close to residential areas, high traffic areas or vulnerable infrastructure (e.g., pipelines, hazardous technical installations, among others). The consequences of poor project planning could pose a risk to human life and significant economic losses, so best practice is to perform a site-specific assessment of turbine locations. It should be noted that in addition to considering such studies in the design phase, other types of management should also be included in the post-construction and operational phases, such as quantitative risk assessments of blade detachment, tower collapse, nacelle and rotor breakage, as well as using simulation tools that comply with international legislation, among others (IEA, 2022, 2025).
It is well known that a critical component of seismic risk lies in the interaction between seismic waves and the specific characteristics of a site, commonly known as site effects (Fatahi, 2014). Soil amplification is also known to be one of the critical phenomena influencing the response of built structures, and it is highly dependent on the properties of the site. Soil amplification is the phenomenon in which soil properties interact with seismic waves to increase vibration at specific frequencies (Dikmen, 2018).
1 Universidad de la República | 2 Agencia Nacional de Investigación e Innovación
In this work, we present the experimental procedure used to estimate the fundamental period of the soil, Tsoil, which is based on the horizontal-to-vertical spectral ratio (HVSR) method, and the fundamental period of the wind tower, Ttower, based on the top-to-base horizontal spectral ratio (HHSR) method proposed by Álvarez (2025).
Energy transition and geosciences
In the context of achieving the 2030 Agenda for Sustainable Development and the energy transition, the United Nations published the Sustainable Development Goals (SDGs) defining aspirations to improve the lives of people and the environment (United Nations, 2015). The SDGs provide targets and indicators to measure the sustainability of both governments and companies, and encourage interaction between these actors.
It is worth noting the importance that geosciences have always played in the extraction and use of natural resources that, in turn, have contributed to the current climate emergency. It should be recalled that seismic methods are the basis of the exploration of oil, gas and other underground resources. However, nowadays earth sciences play a key role in achieving a sustainable and just net-zero carbon energy transition, and in addressing the associated challenges and opportunities. Gardiner et al. (2023) suggested that the current energy transition should minimise threats while exploring and embracing opportunities. The authors show that geoscience sectors – through their skills, knowledge, and data – working in conjunction with existing engineering infrastructures, will play a key role in the energy transition. In their paper the authors summarise the cross-cutting issues that will impact the pace, scale, and style of transition across different sectors and the need for interactions:
• Technical knowledge: Environmental, geotechnical and engineering knowledge, skills, and techniques directly underpin all of the activities. These skills are also important for the design of energy infrastructure, such as wind turbines and transmission infrastructure, soil stability, risk assessment and the laying of underground power transmission cables and pipelines.
• Data availability and access: As pointed out by Gill and Smith (2021) open and transparent data sharing is not a common practice at present. Sharing data accelerates energy transition applications by removing the need to invest in duplicate data acquisition – and the associated social and environmental impacts.
• Multiple uses of the subsurface: It is possible that there are multiple competing or complementary uses of the subsoil. Placement and management decisions, as well as surface control techniques and interoperability of satellite systems, must take into account and manage these multiple uses, while adapting the knowledge acquired over decades.
• Monitoring: Real-time, transparent, and low-cost monitoring approaches should be developed to optimise net-zero engineering applications, as well as to reduce costs, support transparent and open reporting, and build trust among partners. The global wind potential modelled with wind climate data and high-resolution terrain information shows a high potential for development. Gies (2016) emphasised that most wind and solar resource maps lack sufficient detail for companies to select project sites. In order to strengthen energy infrastructure and promote
wind and solar development, site-specific information is required to facilitate investment decision making.
Uruguay’s continental territory has not experienced significant seismic activity. Indeed, there is no rigorous seismic catalogue, only a few records of earthquakes that occurred in the region over past centuries. Given the fact that major infrastructure projects and the development of energy resources have been planned, Benavídez (1998) recommended the establishment of a network for observing geophysical and geodetic parameters as a tool for monitoring and studying seismic risk and hazard, as well as seismicity levels, in the coastal areas of the Río de la Plata Region. The Geophysical Observatory of Uruguay was created in 2010, and seismic monitoring in Uruguay began with the installation of a single broadband seismometer in 2013 (Sánchez, 2018). Due to the scarcity of seismological stations and the low magnitude of the events, there has been no urgent need to study different seismic hazard scenarios.
We envisage future applications of the present work aligned with the SDGs. To prevent and create effective contingency plans, it is necessary to study and simulate different hazard scenarios. In order to simulate these scenarios as closely as possible, data is needed to calibrate the models. Due to the scale at which natural hazards occur, they cannot be faithfully reproduced in university laboratories. Industry has invested in extremely expensive equipment that is not available to universities and research institutes. Therefore, new mechanisms must be created to foster collaboration and interoperability between private companies and universities, and to make that data as available and accessible as possible. Taking advantage of the capabilities of geophysical methods to explore the subsurface, this work presents an analysis of measurements taken at the site of a wind energy generation farm to characterise both the tower’s structure and the surrounding soil.
Geophysical background
Seismic (passive and active) and electrical methods, along with their various techniques and configurations, are most commonly used in soil investigations – such as in landslide studies, slope excavations, and general subsoil prospecting and exploration (McCann, 1990; Parasnis, 1979). Passive seismic refers to the detection of low-frequency natural ground motions.
In this paper two seismic methods were applied: MASW and seismic refraction tomography. Both methods were performed along the same line to obtain information about S- and P-wave velocities: seismic refraction tomography was used to calculate the P-wave velocities, and MASW was used to obtain the 1D model of S-wave velocities. These seismic techniques allowed us to identify substratum interfaces and variations in material compaction (Park, 2018). The HVSR (also referred to as Nakamura method) is a postprocessing technique originally proposed to identify the fundamental frequency of a site or the underlying soil in a specific area, which has recently been applied to civil structures (Nakamura, 1989; Morgan, 2017; Castellaro, 2023, Álvarez, 2025).
MASW seismic technique: The MASW (Multichannel Analysis of Surface Waves) technique analyses Rayleigh waves by processing the signal in the frequency-wavenumber (f-k) domain. This transformation allows for easy separation of Rayleigh wave signals from other seismic waves. Notably, Rayleigh waves
exhibit frequency-dependent propagation velocities, a relationship represented by the dispersion spectrum. The experimental dispersion curve, identified in the f-k domain, corresponds to the spectral peaks (maximum amplitudes) of this dispersion spectrum. This curve provides key insights into subsurface shearwave velocity profiles (Park et al., 1999).
Seismic refraction technique: Studies the subsurface by analysing the travel times of seismic waves refracted at layer interfaces. It involves generating waves (using hammers, explosives, or other sources) that travel through the ground and are detected by geophones. As the waves refract at layers with different seismic velocities, their first arrivals are used to create time-distance graphs, estimating the depth and velocity of each layer. This method is applied in civil engineering, groundwater exploration, and environmental studies, provided that deeper layers have higher velocities than shallower ones.
While cost-effective and efficient for shallow investigations (up to ~100 m), it has limitations: it does not work well in complex terrains with low-velocity layers beneath high-velocity ones or in steeply dipping layers. We use Seismic Refraction Tomography that is a more advanced geophysical imaging technique that reconstructs the subsurface velocity structure by analysing the travel times of refracted seismic waves. Unlike conventional refraction methods (which assume layered models), tomography employs inverse modelling to generate a 2D or 3D velocity distribution, resolving lateral and vertical heterogeneities. This study utilised 24 geophones: 4.5 Hz geophones for MASW and 14 Hz geophones for Seismic Refraction Tomography.
HVSR seismic passive technique: Both natural and anthropogenic background seismic noise contain useful information about the mechanical properties of the subsurface. Ambient noise generated by wind, waves, and distant anthropogenic activities is commonly present in the subsurface at low frequencies, typically below 10 Hz. The HVSR uses this ambient noise to obtain the fundamental frequency of the soil and, with a variation of the HVSR method, it is to obtain the fundamental frequency of wind tower structure.
Ambient noise measurements were collected using a portable seismometer. The TROMINO (Figure 1) is a broadband seismometer that is attached to the soil (or a structure) using three 6-cm long spikes (MoHo, 2025). It was set to record two horizontal (EW, NS) and the vertical (Z or up-down) spectral components of the ambient noise over approximately 20 minutes.
The results from data processing define the fundamental frequency of vibration f0,soil of the soil by means of the HVSR method, which is related to thickness (Nakamura, 1989).
Estimation of fundamental period
To estimate the fundamental period of the soil, Tsoil, and the fundamental period of the wind tower, Ttower, we recorded approximately 20 minutes of ambient noise at different points in the soil and the structure, which is sufficient to capture the longest expected period for this type of structure (Akbaş, 2011).
The recordings were processed using spectral ratio techniques: the HVSR method was applied to free-field measurements to estimate the Tsoil, while the HHSR method was used to estimate the fundamental period Ttower of the tower. For each 20 s window, the Fast Fourier Transform (FFT) was applied to the NS, EW, and Z components at each station of the seismic recordings to obtain the amplitude spectra. For the HVSR method, the spectral ratio is computed as: HVSR(f) = sqrt[NS(f) • EW(f)]/Z(f) and the peak frequency f0,soil is determined from the corresponding HVSR curve at each station. The associated fundamental period is given by Tsoil = 1/f0,soil.
For the wind turbine tower structure, the HHSR method is used. This means that the spectral ratio is determined only between the horizontal components, calculated as a top-to-base ratio. For each 20 s window, the FFT was applied to the NS and EW components at the measurement points located at the top (HV5) and base (HV9) of the tower. This results in the following components: the spectral amplitudes of the wind tower in the NS direction, NStop(f) and NSbase(f), and the spectral amplitudes of the wind tower in the EW direction EWtop(f) and EWbase(f). The HHSR for the two directions is computed as follows: HHSRNStower(f) = NStop(f)/NSbase(f) (for the NS component), HHSREWtower(f) = EWtop(f)/EWbase(f) (for the EW component).
From the two resulting spectral ratio curves, the peak frequencies f0,NStower and f0,EWtower are determined in each direction. The predominant frequency f0,tower was selected as the maximum frequency between these two frequency peaks. Finally, the wind tower’s fundamental period is then estimated as: Ttower = 1/f0,tower The same procedure can be performed to estimate Ttower in relation to some measurement of the foundation (e.g., HV1), rather than from the base.
Geographical site
The area under study is located in the Department of Colonia (coordinates: 34°7′0″ S, 57°41′0″ W), one of the 19 departments that make up the República Oriental del Uruguay. This study is situated a few kilometres from the city of Tarariras, on land belonging to the National Colonization Institute, at 38 km of Route 22. The wind farm has 31 Suzlon wind turbines, model S95, with a hub height of 90 m and a rated power of 2.1 MW, for a total power of 65.1 MW. The investment, which totalled
Figure 1 Station points for the passive seismic survey method on the structure (left) and on the ground (right).
approximately $100 million, had a significant stimulating effect, employing a large number of local workers, and was built jointly by the companies UTE of Uruguay and Eletrobras of Brazil. The wind tower under investigation was tower number 2. Measurements were taken both in the wind tower structure number 2 and in the surrounding soil. Figure 2 shows the area mentioned above with the corresponding tower location indicated (Artilleros Parque Eólico, 2025).
Geophysical surveys
The data collection campaign is shown in Figure 3(b). Field measurements were made at nine selected locations. Three on the foundation (HV1 to HV3), three on the wind tower structure (HV4, HV5, and HV9) and three free-field sites (HV6 to HV8). The free-field sites were located far enough from the wind tower to minimise external noise interference, in the area of the geophysical survey. This survey is defined by two seismic profile lines: the SL1 line, with an east-west (EW) orientation and the SL2 line, with a north-south (NS) orientation.
Methodology
Active refraction and MASW profiling were performed over the same line to provide information about S-wave and P-wave velocities so they can be correlated. Using these seismic techniques we can identify substratum interfaces through sharp increases in velocity, providing a fairly precise general understanding of
Figure 2 Area under study [snapshot taken from Google Earth, 2025]. The red rectangle locates tower number 2 [public information taken from Artilleros Parque Eólico, 2025].
Figure 3 (a) Photo of actual tower structure. (b) Map of the survey with orientation and locations of tower number 2, the ambient vibration measurements for the wind tower and ground, and the seismic profile. Yellow stars indicate HVSR survey locations. Red lines, SL1 and SL2, correspond to the seismic refraction and MASW profiles (both profiles were acquired at the same position).
surface sediments and rock outcrops. Ambient vibrations were measured with the seismometer oriented to magnetic north at the free-field sites.
Results from MASW seismic technique
Contrasts in subsurface properties and a shear wave velocity model (Vs) were obtained from the survey data (Park, 2018). Figure 4 shows the results of the average Vs values for the (a) EW and (b) NS orientations. In the EW orientation the values were: a Vs of 250 m/s for the first layer up to a depth of 10 m; a Vs of 380 m/s for the second layer up to a depth of 16 m; and finally, a Vs of 2800 m/s for the third layer from 16 m downwards. In the NS orientation, the values were: a Vs of 200 m/s for the first layer up to a depth of 7 m; a Vs of 400 m/s for the second layer up to a depth of 22 m; and finally, a Vs of 1200 m/s for the third layer from 22 m downwards.
Results from Seismic Refraction Technique
Figure 5 shows the results of the two-dimensional refraction seismic tomography, which displays the compressional wave velocity model (Vp) with layering that is in good agreement with the results of the MASW survey.
Results from HVSR seismic passive technique
Using the nine measurements taken with the seismometer the data were analysed using the HVSR method for the soil and the structural foundation, and the HHSR method for the structure.
The HVSR data processing was performed using the free software Geopsy (2022), which applies the FFT to 20-second time windows, after filtering the signals as indicated in the SESAME Project (2004).
Foundation: Figure 6 presents the results obtained with the measurements carried out on the foundation. The frequency
peaks determined for the stations HV1, HV2, and HV3 were, respectively, 0.31 Hz, 0.25 Hz, and 0.22 Hz.
Soil: Figure 7 presents the results obtained from measurements carried out on the soil. The frequency peaks determined for stations HV6, HV7, and HV8 were, respectively, 6.25 Hz, 7.19 Hz, and 6.22 Hz.
Figure 4 One-dimensional MASW results. Vs values for (a) EW orientation and (b) NS orientation.
Figure 5 Two-dimensional refraction seismic tomography profiles with Vp values (m/s) for (a) EW orientation and (b) NS orientation.
Figure 6 Ambient noise analysis results at points of the foundation: (a) HV with the interpreted peak frequency; (b) Amplitude Spectral Density (ASD) for the three components.
Table 1 Results obtained.
Figure 7 Ambient noise analysis results at points of the soil: (a) HV with the interpreted peak frequency; (b) ASD for the three components.
Wind tower: The total height of the tower is approximately 87.55 m (excluding the gondola). Inside the tower, measurements were taken at three heights measured from the base: 0.0 m (HV9), 19.0 m (HV4), and 39.50 m (HV5). The point HV9 is shown in Figure 8(a). Figure 9 presents the results obtained with the HHSR method for the wind tower. The frequency peaks determined for each horizontal component were: f0,NStower = 1.03 Hz for the NS component, and f0,EWtower = 0.94 Hz for the EW component. This gives the estimated fundamental frequency of the tower, f0,tower = 1.03 Hz.
Table 1 summarises the calculated peak frequencies and fundamental periods.
Conclusions
The HVSR and HHSR methods were applied to obtain the fundamental frequencies and periods of a wind tower structure and the underlying soil of an operating wind generation park. These results will be used to calibrate numerical models in future studies aimed at evaluating the effects of soil-structure interaction on the wind tower structure under seismic or other hazardous events.
Acknowledgments
The authors would like to thank the manager of Artilleros Parque Eólico, Emanuel Cesán, and his technicians Facundo Abbona
Figure 9 Horizontal component of the ambient noise analysis. (a) HH curve highlighting the interpreted peak frequency. (b) ASD for the two horizontal components.
Figure 8 (a) Location of the HV9 point on the base of the tower. (b) View of the soil in the EW direction on the seismic line LS1.
and José Delgado for their support, and Daniel Mogollón and his technician Pino Wilmer for their support and the provision of instruments.
References
Akbaş, B., Fahjan, Y., Shen, Y., Siyahi, B., Umut, Ö. and Korkmaz, B. [2011]. Design considerations and seismic performance of wind turbine towers considering soil-structure interaction. Turkey Earthquake Engineering and Seismology Conference, Ankara, Extended Abstract
Álvarez, I.F., Velásquez, A.S., Pinzón, L.A., Alva, R.E. and Gonzalez-Drigo, J.R. [2025]. Identification of buildings in Panama’s Old Quarter (Casco Antiguo) with resonance potential during earthquakes. Structures, 79(2025), 109601.
Artilleros Parque Eólico [2025]. Online in: https://artilleroseolica.com.uy. Benavídez, A. [1998]. Sismicidad y sismotectónica en Uruguay. Física de la Tierra, 10, 167-186.
Castellaro, S. and Musinu, G. [2023]. Resonance versus Shape of Sedimentary Basins. Bull. Seismol. Soc. Am., 113(2), 745-761.
Dikmen, S.Ü. and Tanırcan, G. [2018]. Site amplification and resonance frequency in the urban environment. Soil Dynamics and Earthquake Engineering, 105,160–70.
Fatahi, B., Tabatabaiefar H. and Samali, B. [2014]. Soil-structure interaction vs site effect for seismic design of tall buildings on soft soil. Geomechanics and Engineering, 6(3), 293-320.
Gardiner, N.J., Roberts, J.J., Johnson, G., Smith, D.J., Bond, C.E., Knipe, R., Haszeldine, S., Gordon, S. and O’Donnell, M. [2023]. Geosciences and the Energy Transition. Earth Science, Systems and Society, 3, 10072.
GEOPSY. [2024]. Online in: www.geopsy.org
Gies, E. [2016]. Can wind and solar fuel Africa’s future? Nature, 539, 20-22.
Gill, J.C. and Smith, M. [2021]. Geosciences and the Sustainable Development Goals. London: Springer Nature.
Google Earth [2025]. Online in: https://earth.google.com Hau, E. [2006]. Wind Turbines: Fundamentals, Technologies, Application, Economics. Springer-Verlag.
International Energy Agency – IEA. [2022]. Wind September 2022. In: https://www.iea.org/energy- system/renewables/wind. Licence: CC BY 4.0.
International Energy Agency – IEA. [2025]. Global Energy Review 2025, IEA, Paris. Online in: https://www.iea.org/reports/global-energyreview-2025, Licence: CC BY 4.0.
Martín del Campo, J.O. and Pozos-Estrada, A. [2020]. Multi-hazard fragility analysis for a wind turbine support structure: An application to the Southwest of Mexico. Engineering Structures, 209, 109929. McCann, D.M. and Forster, A. [1990]. Reconnaissance geophysical methods in Landslide investigations. Engineering Geology, 29, 59-78. Ministry of Environment. [2021]. ECLP - Estrategia Climática de Largo Plazo. Sistema Nacional de Respuesta al Cambio Climático. Online in: https://www.gub.uy/ministerio-ambiente/politicas-y-gestion/ estrategia-climatica-largo-plazo-uruguay.
MoHo, S.R.L. [2025]. Online in: https://moho.world/en/moho/ Morgan, D.J.R., Raines, M.G., Thorpe, S., Castellaro, S., Bailey, E. and Wilby, P.R. [2017]. Passive Seismic Surveying. A new and cost-effective site-assessment tool for the quarrying industry. Quarry Management, March, 20-22.
Nakamura, Y. [1989]. A Method for Dynamic Characteristics Estimation of Subsurface Using Microtremor on the Ground Surface. Q. Rep. Railw. Tech. Res., 30, 25-33.
Parasnis, D.S. [1979]. Principles of Applied Geophysics. Springer.
Park, C., Richter, J., Rodrigues, R. and Cirone, A. [2018]. MASW applications for road construction and maintenance. The Leading Edge, 37(10), 724-730.
REN21 [2023]. Renewables 2025 Global Status Report Collection, Renewable Energy Systems and Infrastructure. Online in: https:// www.ren21.net/gsr-2025/downloads/pdf/go/GSR_2025_GO_2025_ Full_Report.pdf.
Sánchez, L., Suárez, N., Campal, N., Loureiro, J., Curbelo, A., Castro, H., Rodríguez, M., Latorres, E., Castro, O., Arduin, F., Faraone, M., Pascale, A. and Abelenda, E. [2018]. The New National Geophysical and Geodetic Network (Uruguay). Seismological Research Letters, 89(2A), 458.
SESAME Project [2004]. Guidelines for the implementation of the H/V spectral ratio technique on ambient vibrations. Measurements, processing and interpretation. WP12, Deliverable N. D23.12.
United Nations [2015]. Transforming Our World: The 2030 Agenda for Sustainable Development, New York, NY: United Nations. Uruguay XXI [2022]. Energías Renovables en Uruguay. Promoción de Inversiones, Exportaciones e Imagen País. Enero 2022. Available Online in: https://www.uruguayxxi.gub.uy.
CALENDAR OF EVENTS
1-4 Sep World CCUS Conference www.wccus.org
7-11 Sep Near Surface Geoscience Conference and Exhibition (NSG) 2025
- 31st European Meeting of Environmental and Engineering Geophysics
- 6th Conference on Geophysics for Mineral Exploration and Mining
- 4th Conference on Geophysics for Infrastructure Planning, Monitoring and BIM
- 1st Conference on Geohazards Assessment and Risk Mitigation
- 1st Conference on UXO and Object Detection www.eagensg.org
7-11 Sep 32 nd International Meeting on Organic Geochemistry (IMOG) www.imogconference.org
9-11 Sep Second EAGE Conference and Exhibition on Guyana-Suriname Basin www.eage.org
14-18 Sep Seventh International Conference on Fault and Top Seals www.eage.org
15-17 Sep Fifth EAGE Workshop on Assessment of Landslide Hazards and Impact on Communities www.eage.org
15-18 Sep AOW Energy 2025 www.aowenergy.com
16-18 Sep The Middle East Oil, Gas and Geosciences Show (MEOS GEO) www.meos-geo.com
17-18 Sep First EAGE Workshop on Energy Transition in Latin America’s Southern Cone www.eage.org
29 Sep1 Oct Second AAPG/ EAGE Mediterranean and North African Conference (MEDiNA) medinace.aapg.org
29 Sep1 Oct Eighth EAGE Borehole Geophysics Workshop www.eage.org
7-11 SEPTEMBER 2025
6-8 Oct Second EAGE Data Processing Workshop www.eage.org Barcelona Spain
6-8 Oct Empowering the Energy Shift - The Role of HPC in Sustainable Innovation: Ninth EAGE High Performance Computing Workshop www.eage.org Barcelona Spain
6-9 Oct GEOTERRACE-2025: International Conference of Young Professionals www.eage.org
14-16 Oct First EAGE Conference on the Future of Mineral Exploration: Challenges and Opportunities www.eage.org
15-16 Oct 3 rd EAGE/SUT Workshop on Integrated Site Characterization for Offshore Renewable Energy www.eage.org
de Chile Chile
21-22 Oct First EAGE Workshop on Geophysical Techniques for Monitoring CO2 Storage www.eage.org Toronto Canada
21-23 Oct First EAGE/ AAPG/ SEG Carbon Capture Utilisation and Storage Workshop (CCUS) www.eage.org Al Khobar Saudi Arabia
27-31 Oct 6th EAGE Global Energy Transition Conference & Exhibition (GET 2025) - EAGE Carbon Capture and Storage Conference
- EAGE Geothermal Energy Conference
- EAGE Hydrogen and Energy Storage Conference
- EAGE Offshore Wind Energy Conference www.eageget.org
The Netherlands
28-30 Oct 2 nd Edition AAPG/EAGE Petroleum Systems of the Middle East GTW www.eage.org Kuwait City Kuwait November 2025
2-5 Nov EAGE/AAPG Workshop on Tectonostratigraphy of the Arabian Plate: Structural Evolution of the Arabian Basins www.eage.org Riyadh Saudi Arabia
10-11 Nov EAGE Workshop on Enhancing Subsurface Practices using AI/ML www.eage.org
10-12 Nov Seventh EAGE Rock Physics Workshop www.eage.org Cape Town South Africa
