Gazpromneft-Sakhalin, a subsidiary of Gazprom Neft, has completed drilling of a prospecting and appraisal well at its Ayashsky license block, located on the continental shelf of the Okhotsk Sea.
Gazprom Neft said last week that a new hydrocarbon field was discovered, with initial in-place reserves estimated at 255 million tonnes of oil equivalent (Mtoe).
The company added that a detailed assessment of these reserves would be prepared by mid-2018.
Alexander Dyukov, CEO of Gazprom Neft, said: “We continue the development and exploration of all offshore license blocks in our portfolio. The discovery of a major field in the Okhotsk Sea proves the relevance of our experience and allows us to reassess prospects for developing offshore projects.”
According to the company, the construction of the well was completed during a narrow window of an ice-free period at the Okhotsk Sea, on time, and without incident.
“The decision to drill at the Ayashsky prospective formation was taken on the basis of 3D seismic data. Exploration data received during offshore works at the Okhotsk Sea was carefully analyzed prior to the development of the drilling program,” the company said.
Core samples running to 162 meters were taken from anticipated productive strata for the construction of the 2,700-metre-deep well, in addition to open- and closed- geophysical and hydrodynamic borehole exploration work.
The Gazpromneft-Sakhalin-operated Ayashsky block in the Okhotsk Sea forms part of the Sakhalin-3 project. The block is located in the northeastern part of Sakhalin Island’s continental shelf some 55 kilometers away from the coast.