KEYS TO HIDDEN TREASURES OF WESTERN SIBERIA: MULTI-STAGE FRAC
The modern world needs more and more energy every day. At the same time production of oil, the main source of energy, becomes more and more hard-toget; the explored reserves of this valuable natural resource are declining all over the world. This is where new technologies come to help out: they make it possible to produce hydrocarbon reserves which were inaccessible as far as several years ago. Multistage hydraulic fracturing for Bazhenov formation development is one of such innovations.
The Bazhenov formation is a bed of shale and low permeable rock stretching virtually underneath the entire Western Siberia. Geological plays like this are common in other regions in Russia and the world — for instance, pilot development is actively underway in the USA and Canada. As calculated by experts, the Bazhenov formation resources alone may account for 500 million to 20 billion tons. The oil from this geological formation is light, low in sulphur, with low content of other impurities, which is the evidence of its highest quality. The Bazhenov formation hydrocarbons are currently produced predominantly by conventional methods whereby about 5—10% of resources available are delivered to the surface.
Applying multi-stage hydraulic fracturing (frac) in horizontal wells may make the Bazhenov formation development several times as efficient. Drilling horizontal multi-frac wells is the most efficient technology out of all solutions tested in the course of developing the deposits which are similar to the Bazhenov formation in terms of properties. This formation stimulation method is currently actively applied for oil production from low permeable reservoirs all over the world. The essence of the technology is consecutive execution of several fracs in a single horizontal well. As a result of this work, cracks are formed in the formation, through which proppant — a pellet-type material — is injected into the well, which prevents closure thereof during field development life. Presence of such cracks makes it possible to substantially enhance formation conductivity and therefore increase the well drainage area and the volume of hydrocarbons recovered from the formation.
Salym Petroleum, a joint venture of Shell and Gazprom Neft, is executing a pilot project for implementation of this innovation in Russia.
It has been developing the Salym group of fields in Western Siberia since 2003. The company has effectively adopted new technologies in well construction, oil production, safety and environmental protection. Salym Petroleum has been the first company in Russia to have its complete stock of wells equipped with the Smart Fields technology to remotely monitor and manage the wells. Meanwhile, usage of modern Russian drilling rigs and advanced managerial solutions made it possible for the company to substantially reduce well drilling and completion time.
From the very start of the development of the Salym group of fields, Salym Petroleum has been involved in a largescale theoretical and practical work in terms of Bazhenov formation development methods. Within as little as the last three years, the company has drilled three vertical appraisal wells, performed 3D seismic, retained a core, performed a broad set of geophysical studies, as well as executed an extended testing of two wells in order to evaluate production outlook for the Bazhenov formation.
At the end of 2013 SPD spudded the first one out of five horizontal Bazhenov formation appraisal wells. In 2014-2015, the company will perform a multi-stage frac and the required set of well tests there. This will make it possible for Salym Petroleum specialists to obtain data on the initial flow rate and evaluate the potential of the Bazhenov formation in detail. In case the application of multi-stage fraccing technology on the Salym group of fields proves successful, it can be replicated at other fields in Western Siberia. Companies will be able to substantially increase production, the state budget will receive additional tax payments, new jobs will be created, and the business will gain development momentum. This will inure to the advantage of the entire region and the country as a whole.
The multi-stage fraccing technology is one of many innovations Salym Petroleum is actively implementing. Applying it as well as other advanced technologies, the company discovers new horizons for efficient natural resource development and substantially contributes to ensuring global energy security.
Š2014 Salym Petroleum Development N.V. www.salympetroleum.com