UPDATE 1-PetroChina buys Canada shale stake from Shell

By Alison Lui

HONG KONG Feb 2 (Reuters) - PetroChina Co Ltd said on Thursday it has signed an agreement to buy a 20 percent stake in a shale gas project in Canada from Royal Dutch Shell Plc, the latest in a series of overseas acquisitions by Chinese state energy giants.

The deal to buy into Shell's 100 percent-owned Groundbirch assets was completed on Wednesday, PetroChina spokesman Mao Zefeng told Reuters, declining to reveal the value of the acquisition.

Citing market talk, FinanceAsia said in a report on Wednesday that PetroChina was planning to buy the Groundbirch stake for more than $1 billion.

The transaction, the latest in a string of investments by Chinese oil companies in North American shale gas and oil sands, had been approved by both the Chinese and Canadian authorities, Mao said.

According to Shell's website, the Groundbirch project, located in British Columbia, has the potential to produce 1 billion cubic feet equivalents (bcfe) per day and an estimated producing life of 40 years.

PetroChina and other Chinese state oil giants, including China Petroleum & Chemical Corp (Sinopec) and CNOOC Ltd have been scouring the world for reserves to fuel China's rapidly-growing economy.

Shale gas and oil sands assets in North America have been a focus in the past year as Chinese companies seek operational experience in the relatively frontier area.

CNOOC completed a C$2.1 billion ($2.04 billion) acquisition of Opti Canada Ltd in November, giving China's top offshore oil company its second stake in a Canadian oil sands property.

China Petrochemical Corp, parent of Sinopec, signed a deal to buy Canadian oil and gas explorer Daylight Energy Ltd for C$2.2 billion ($2.1 billion) in October.

In June, PetroChina and Canada's Encana Corp called off an announced $5.6 billion deal that would have given the Chinese group a 50 percent stake in some of Encana's shale gas assets.