This year, two out of three fields in Sakhalin Island, the base of the offshore projects being executed with Rosneft’s involvement in the Okhotsk oil and gas province, are marking important anniversaries.
The period from 1977 through 1993 became a key milestone in tapping the oil, gas and condensate potential of the northeastern shelf of Sakhalin. Exploration of the shelf resulted in a number of promising oil and gas discoveries – Odoptu in 1977, Chaivo in 1979, Arkutun-Daghi in 1989.
Chaivo – 35 years (1979)
The Chaivo field, which is being developed as part of the Sakhlain-1 project, is marking 35 years since its discovery this year. Commercial production from the field began in late 2005. A unique cutting-edge drilling rig, Yastreb, and an offshore platform, Orlan, are being used to develop Chaivo. Currently, the oil wellstock in the field amounts to 40 development wells many of which set records in the total and horizontal borehole length and drilling rate.
The Yastreb onshore drilling rig was specially designed for the Sakhlain-1 project and is one of the most powerful onshore drilling rigs in the industry. It is designed to drill extended-reach wells from the shore. The Orlan offshore platform is located in the Sea of Okhotsk, 11 km away from the shoreline. It can withstand extremely cold weather, up to 8-magnitude seismicity, up to 13 m high wave and up to 6 m high ice and ice ridges. The platform operates 20 wells with the longest wellbore reaching 12.3 km.
The product is moved from Yastreb and Orlan to the Chaivo Onshore Processing Facility and then to the loading terminal in De-Kastri, Khabarovsk Territory, wherefrom in October 2006 export of oil to Asia Pacific countries began. Gas produced by Sakhalin-1 has been supplied to consumers in Russia’s Far East since 2005.
Arkutun-Daghi– 25 years (1989)
Arkutun-Daghi development is the next phase of the Sakhalin-1 project. In 2014, 25 years after discovery, the field became worldwide known due to the Berkut offshore platform: the platform is designed to operate in harsh sub-Arctic conditions with the wave height of up to 18 m, ice cover of up to 2 m and the temperature of up to -44 °?. Installation of the platform topsides required a unique towing operation to bring them to the platform location. The world largest ocean barge, 260 m long and 63 m wide, was used to tow the structure to destination and then install. The operation set a world record in the total weight of the integrated topsides installed by sliding in the conditions of open sea. The weight of that gigantic structure is 42 000 t, including over 1900 km of cable and over 97 km of piping.
Production from Arkutun-Daghi is expected to begin in late 2014. The project will bring in material investment to the economy of the Far-Eastern region.
Adapted from press release by Cecilia Rehn
Read the article online at: https://www.oilfieldtechnology.com/exploration/20102014/rosneft-celebrates-anniversaries-for-sakhalin-oil-and-gas-fields/