UPDATE 1-Sinopec Chuanxi resumes 40 pct gas output after quake

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BEIJING, May 21 (Reuters) - Sinopec Corp's (0386.HK) Chuanxi gasfield has restored natural gas output to about 40 percent of its normal levels nearly a week after a powerful quake disrupted production, a company paper reported on Wednesday.

As of Sunday, gas output in the field close to regions badly hit by the 7.9 magnitude quake had reached more than 3 million cubic metres a day, the China Petrochemical News reported.

The field's output was reduced to 10 percent of its capacity of 8 million cubic metres per day after the earthquake on May 12 forced the closure of chemical plants that use gas, which led Sinopec to shut down nearly 1,000 wells.

After safety checks and repairs, all production and transport facilities in the gasfield are now ready for full-scale operation, and can increase output if gas users restore operation, the report said.

Gas supply to Chengdu, the capital of earthquake-devastated Sichuan province, by Sinopec's Southwest Petroleum Company that runs the gasfield has resumed to over 3 million cubic metres a day, largely the same as before the quake, the paper added.

Southwest Petroleum Company produced 2.7 billion cubic metres of gas in 2007.

Gas production in Sichuan accounts for nearly a quarter of China's total and PetroChina (0857.HK) is the lead operator.

(Reporting by Jim Bai; Editing by Anne Marie Roantree)