Consulting in the Nordic region
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RK’s consultants focus on providing value-adding services to mining and exploration clients including major and junior mining and exploration companies, as well as lending institutions. Recent developments in geopolitics are increasing the importance of the supply of domestic raw materials in Europe where northern Europe plays a major role. Therefore, it is a vital part of the mining business that consulting practices offer services for exploration, mining, and operational support by bringing knowledge and best practices to the industry. SRK supports clients on due diligence studies, valuations, CPRs, financial modelling, open pit and underground rock mechanics and mine planning, rock mass and water numerical modelling, mineral resource estimation, geological modelling and on the geotechnical engineering of operations. This article will give some insights to projects that SRK has recently been involved with in Finland.
Geotechnical Data in Nordic Projects Beyond RQD Whilst geotechnical data is vital to operating pits and underground mines, simple rock mass quality data can provide a solid foundation for an understanding of the rock mass at an early stage in a mining study process. This data can be collected from the initial resource drilling programmes for little extra time and cost but adding large technical value to a project. 14
MATERIA 5 – 2023
As a result, and as the project matures from advanced exploration into early-stage mining assessments, there is a platform of data which limits the extent and requirement for specific geotechnical and hydrogeological drilling campaigns with associated cost and schedule savings to the project advance through the study stages. SRK’s experience in the Nordic region has highlighted that there is generally a good acknowledgement for basic geotechnical data collection during geological logging campaigns. However, this is often limited to core recovery, measurement of RQD, and some structural logging of the oriented core - with the standard and quality of many data sets variable. The cause of poor-quality geotechnical data at the resource drilling stage is often simply a lack of understanding of why the data is collected and how it is applied. With simple training, the context and value of how geotechnical data will eventually be applied in mining studies will be understood by the existing geological logging teams. The project owners are better informed of the value of the data they collect (for minimal additional effort) and it is then useful for elements of rock mass characterisation and hydrogeological appraisal which assists early-stage mining studies. SRK has developed or adapted the existing logging systems for several clients in order to establish an industry accepted standard in useful geotechnical data capture. Existing logging
systems that operate in generic or proprietary software systems have been re-organised and modified to meet a minimum standard of rock characterisation to enable the calculation in various rock classification systems. Additionally to RQD correctly collected the introduction of the collection with a few other parameters enables the confident calculation of ratings in multiple rock classification systems. Each system has 3-4 categories, but if an extra 1-2 parameters are collected, then independent calculation in the various classification systems is possible. After basic training to the same logging team, the logging time increases by 10-20% to collect enough parameters to estimate rock strength, frequency of open fractures, how many sets (similar 3D orientation) of fractures, and what is the condition of the fractures and infill. When ‘full’ geotechnical logging is done to characterise the rock mass, logging parameters are chosen to calculate ratings for a rock mass classification system independently. Conversion formulae are possible but should not be blindly applied as they were not originally established for extensive application in every rock mass environment. The quality and volume of oriented core for point structural logging is generally good in Nordic programs. Additional to resource modelling, the orientation and spacing of fractures is vital to understand the block sizes of the rock mass in 3D - and the joint surface and infill condition can also be logged easily
