Gazprom Neft has undertaken 3D 4C seismic works using “CRAB” seabed stations at the Ayashsky license block. Covering 515 square kilometres, over a period of more than four months, these investigations have proved the most extensive in Russia and the only such investigations using 3D 4C technology in 2019.
CRAB seabed stations are a unique Russian-produced solution, created following a joint project between Gazprom Neft, the Ministry of Trade and Industry of the Russian Federation, JSC Marine Arctic Geological Exploration, and the International Tomography Centre (ITC SB RAS). Oil and gas companies have, hitherto, had to use existing foreign-produced equipment for seismic operations of this kind.
An exclusively Russian development, CRAB seabed stations are not only competitive with well known international alternatives, but outstrip them on a number of criteria, having previously proved themselves in pilot testing at Gazpom Neft’s offshore license blocks before being put into full commercial operation. Two thousand eight hundred seabed stations, manufactured for the 2019 field season, have been used in seismic works at the Neptune field, involving four vessels and more than 150 specialists.
Processing of field material has confirmed the high quality and informational value of the seismic data obtained, allowing Gazprom Neft subsidiary Gazprom Neft Shelf (the client in this case) to prepare proposals on expanding the scope for using seabed stations. The Ministry of Trade and Industry has already allocated funds to further develop this project, and to develop new-generation “CRAB 2.0” stations, which will be tested on the Arctic shelf throughout 2021 before going into commercial production.
«The Sakhalin Island continental shelf, where Gazprom Neft is developing an oil-production cluster, is of considerable strategic importance. Thanks to the deployment of new technologies, and support for cutting-edge domestic developments, we are able to undertake high-quality seismic investigations in the Sea of Okhotsk and obtain more accurate results. CRAB seabed stations record more information, which means we can construct more reliable geological and geophysical models, thus reducing geological risks».Sergei Chigai Acting CEO, Gazprom Neft Shelf
«The work undertaken at the Ayashsky license block has proved the most extensive project in Russia this year, both in terms of duration and the number of specialists and the volume of seabed equipment involved, including MAGE’s own research vessel, the Nikolay Trubyatchinsky. Russian-developed seabed stations have proved themselves in the Sea of Okhotsk. Data obtained with their assistance is highly informative and of high quality, confirming their ability to compete with equipment from foreign manufacturers».Alexey Kazanin Chairman of the Board of Directors, MAGE
“CRAB” seabed stations form part of a joint project between Gazprom Neft, the Ministry of Trade and Industry of the Russian Federation, JSC Marine Arctic Geological Exploration, and the International Tomography Centre (ITC SB RAS). The CRAB seabed station is a mobile hardware and software appliance for marine seismic surveying and monitoring, used in transit zones and offshore. Built from four-component autonomous seabed stations, serviced through the station’s container-laboratories, the CRAB station is designed for local seismic surveys and exploration at offshore hydrocarbon fields.
The Ayashsky license block in the Sea of Okhotsk is located 55 kilometres offshore from Sakhalin Island, in the north—east of the island’s continental shelf, where sea depths can reach up to 90 metres. The Neptune field (with reserves in place of 415 million tonnes (mt) of oil) was discovered in 2017, and the Triton field (with reserves in place of 137 mt) in 2018.
JSC Marine Arctic Geological Expedition (MAGE) has been providing a wide range of geological and geophysical services consistent with international quality and health, safety and environmental standards since 1972. The mission of MAGE is to promote the scientific and technological progress and well-being of society by providing the geological information necessary to replenish the mineral and energy resources base of the continental shelf.