(EnergyAsia, February 28 2012, Tuesday) — A consortium led by US major Chevron Corp plans to spend US$5 to US$6 billion in a five-year drilling programme as part of an estimated US$20 to US$25 billion project to further develop Central Asian country’s biggest producing oil field.

Chervon’s 50%-owned the TengizChevroil LLP venture will drill Kazakhstan’s Tengiz field to raise oil output to between 820,000 and 870,000 b/d b y 2017 from 570,000 b/d now. The field’s production fell by 0.4% to 565,000 b/d last year.

The other members of the TengizChevroil LLP venture are ExxonMobil, which holds a 25%, a Russian oil company, LukArco (5%), and the government of Kazakhstan, which owns 20% through state oil company KazMunaiGas.

Discovered in 1979, the Tengiz field on the northeast shore of the Caspian Sea is one of the largest hydrocarbon discoveries in modern times, holding as much as 25 billion barrels of oil and nearly 13 trillion cubic feet of natural gas