Мурманская МИЛЯ. 2018 г. №4.

EXPLORATIONS 56 velopment work to replace foreign-made hy­ drophones with domestic ones. We plan to conduct tests next year. As a result, it was possible to make the single technology cluster of seismic surveys on the shelf, in the transit zone and onshore with high quality seismic dataset. The works performed in the transit zone in recent years start a new stage of technical development in the industry and make it possible to perform multicomponent (4C) seismic surveys in the Arctic providing a gradual transition to multi­ component seismic studies. High Resolution Seismic Survey Engineering exploration is a relatively new activity of the Company. While remaining the targeted focus on the Company innovation development, we have succeeded in gras­ ping a new exploration trend that is engine­ ering surveying which have not been carried out by JSC MAGE until quite recently. When entering this market, we knew that we had to propose something new that other com­ panies were not able to do. As a result of the Company’s innovation policy, during the last few years we have succeeded in deve­ loping a modern system of the Arctic Shelf engineering survey which are in demand by the leading Russian oil and gas companies, namely Rosneft and Gazprom. Currently, the Company carries out the full range of en­ gineering surveys. Along with conventional study methods (drilling, sampling, high-fre­ quency geoacoustics), we would like to men­ tion the innovation technologies used by JSC MAGE for conducting geophysical sur­ veys when performing engineering surveys. Speaking of the innovation methods, first of all we would like to emphasize a high resolu­ tion seismic survey, an ultra-high resolution seismic survey and ROV operations. In the first turn, we use high and ultra- high resolution seismic surveys for detailed breakdown of the near-surface section with a view to detecting gas lenses and gas hy­ drate deposits as well as forecasting clusters of shallow gas in the near-surface section. Timely detection of gas clusters is a crucial task when exploring and developing hydro­ carbon fields on the shelf. Excessive forma­ tion pressures arising in such gas pockets present significant risks when constructing wells and deploying underwater facilities. One of the reasons of the focused attention to this issue was the accident on Well 2 in the Sea of Okhotsk. The most important element of high reso­ lution seismic technology is a recording sys­ tem based on a specialized seismic streamer. If at the first stage of this level work we used the Dutch Hydroscience Technologies spe­ cialized solid streamer with a 6.25-m interval between sensors [3], but now “at the time of sanctions” we perform this type of survey us­ ing modern domestic-manufactured equip­ ment of the Russian company Si Technology (Gelendzhik) with comparable parameters. This is a Russian 192-channel digital streamer of XZoneBottomFish model with the active length of 1,200 m. A distinguishing feature of the recording system is a reduced inter­ val between the streamer channels (6.25 m and 3.125 m) that makes it possible to significantly increase the detail of a seis­ mic section [2]. The streamer stabilization at a given depth is carried out using Digi- Bird 5011Е compass depth controllers. The streamer position is continuously shown on the DigiCOURSE managing controller display in tabular and graph forms. At the end of the streamer there is a PartnerPlast 800L tail buoy equipped by a flashing beacon, a ra- dar-reflector and a GNSS-receiver. Penetration depth is about 1 km under the resolution capability of 2-5 m depending on the sedimentary cover geological structure. A solid ecologically friendly design of the overboard part of the receiving device plays an important role. It is worth mentioning that while conducting these studies the foreign- made technical facilities are used along with domestic equipment. As an elastic wave source, the cluster consisting of 4 G.GUN II air guns (with a vo­ lume of 150 to 40 cu. in. each) is used. These air guns are the most advanced in their class due to their high efficiency in the most dif­ ficult conditions. There is also an alternative source consisting of 4 SleeveGun air guns with a volume of 40 cu. in. each. Automatic control and gun operation synchronization is exercised by means of BigShot controller with time resolution of 0.1 ms. Additionally the air gun controller receives the information on the air gun cluster depth. The Russian EK 2VM-5 221 high-pressure compressor of the Krasnodar Compressor Plant is used to fill the guns with air to the pressure of 2,000 psi. Seismic data interpretation was carried out using the Kingdom Software package. For a more convenient ranking of anoma­ lous zones, the main reflecting horizons were identified in the section under study. A de­ tailed analysis of seismic sections showed the presence of a large number of amplitude anomalies of different thickness and sizes within the identified seismic zones. For the first time, the Company used this technolo­ gy in the water area of the Shtockman gas condensate field in the Barents Sea [9]. Ac- MURMANSK MILE • 4-2018