Second success for Sakhalin 5; BP, Rosneft test at CJSC Elvary Neftegas

A joint venture of Rosneft and BP has hit oil in a second exploratory well in the Sakhalin 5 acreage northeast of Sakhalin Island. The venture, called CJSC Elvary Neftegas, announced the new discovery Oct. 7.

The Udachnaya well reached a total depth of 8,875 feet, finding hydrocarbons in three zones. One of the zones was tested at a flow rate of 1,900 barrels of oil daily through a 28/64-inch choke, Elvary Neftegas reported.

The new well was drilled by the Transocean Legend semi-submersible rig in water about 330 feet deep on the Udachnaya structure. The location is about 25 miles off Sakhalin in the Sea of Okhotsk.

2004 well hit oil and gas

An earlier well about 10 miles to the east of Udachnaya, also in the Kaigansky-Vasuykansky exploration license area, encountered “significant volumes of oil and gas in a number of high-quality sandstone reservoirs,” according to the Rosneft-BP venture. That well, on the same license, was drilled in 2004 on the Pela Lache structure in about 370 feet of water.

Exploratory drilling will continue next year, according to Elvary Neftegas, as will 3-D seismic work. A joint team of BP and Rosneft geologists is studying the well results and 3-D seismic shot from July to October on about 750,000 acres in the Sakhalin 5 area.

Sakhalin 5 includes the Vostochno-Schmidtovsky sector as well as the Kaigansky-Vasuykansky area. Estimates of reserves in the zone range as high as 4.4 billion barrels of oil and 21 trillion cubic feet of natural gas.

Rosneft holds 51 percent of the joint venture, and BP 49 percent.

—Allen Baker