Gazprom Neft has successfully carried out electrical prospecting (to a length of 3000 km) throughout an area of approximately 600 km2 at the Tympuchikansky and Vakunaysky blocks (the Chonsky project) in Eastern Siberia.
Near-field transient electromagnetic (TEM) method
The recently completed works represent the most significant research to date undertaken through the use of near-field transient electromagnetic (TEM) method, not just in Eastern Siberia, but in the world. Records were broken not just in the extent of electromagnetic field sources and the number of signals received (at around 1200 and 7600, respectively), but also the duration of the works – undertaken since December 2013 without any break for the off-season. These investigations have allowed the collection of a significant volume of new geological information on the Tympuchikansky and Vakunaysky blocks. Electrical prospecting of around 1500 km was also undertaken at a third field within the Chonsky group, at the Ignyalinsky block.
Near-field transient electromagnetic survey is just one part of a comprehensive programme of geological prospecting being undertaken by Gazprom Neft at the Chonsky group fields – the combination of seismic and electrical prospecting allowing more accurate mapping of geological formations. Highly precise 3D seismic prospecting reveals the existence of potential reservoirs (and their shape), while electromagnetic frequencies can indicate the extent to which such formations are saturated with hydrocarbons. The large number of transmitters used at the Chonsky project allows deep coverage of the zone under investigation, forming the basis for more detailed maps of the resistance of various layers, at various depths (from 50 -1700 m at the Chonsky fields).
Electrical prospecting at all three fields of the Chonsky project will be continued in January 2015, with a total 7500 m to be covered in the next season, using new recording equipment currently undergoing testing – something which is expected to both shorten the lead time while improving the effectiveness of such work.
First Deputy CEO Vadim Yakovlev commented: “The establishment of a new Gazprom Neft E&P centre in Eastern Siberia is a major strategic focus for the company. The entire region is noted for the low level of geological research undertaken here, so the new, precise data we are collating through the use and integration of various cutting-edge geological prospecting techniques will allow us to develop an optimally effective model of these fields, allowing us to begin commercial production in a few years’ time.”
Adapted from press release by Cecilia Rehn
Read the article online at: https://www.oilfieldtechnology.com/exploration/23122014/gazprom-neft-eastern-siberia-fields-sets-world-record-in-electrical-prospecting/