(Updates with details throughout, more refineries say operations un affected)

BEIJING, May 12 (Reuters) - Refineries in China and nearby countries appear to have escaped largely unscathed from a magnitude 7.5 earthquake that struck southwestern China on Monday and was felt as far away as Thailand, industry sources said.

The epicentre of the quake was Sichuan province, the U.S. Geological Survey said, an area where there are no large oil processing plants but several major gas fields.

PetroChina's <PTR.N><0857.HK> 200,000 barrel per day (bpd) Lanzhou refinery, the largest in Western China and likely the closest major plant to the epicentre, was shaken but appeared undamaged, a company source told Reuters.

Sinopec <SNP.N><0386.HK> and PetroChina, which operate fields and pipelines in the area, could not immediately be reached for comment. Some fixed telephone lines to parts of Sichuan near the quake appeared to be down.

Other major plants including PetroChina's Jinling and Sinopec's major Maoming, Zhenhai and Gaoqiao refineries were unaffected by the tremor, officials at those facilities said.

Ports including the key Ningbo crude receiving terminal were also operating normally, sources at the ports said, although the quake was felt along much of the coast.

There were no visible signs of damage to the massive Three Gorges Dam, a key hydropower facility.

Taiwan also felt the tremor but there were no immediate reports of damage to any of its refineries, industry sources with government-owned CPC Corp [CHIP.UL] and Formosa <6505.TW> said.

Officiails with several of Thailand's refineries also said their operations had not been affected by the quake. (Reporting by Jim Bai, Aizhu Chen and Emma Graham-Harrison, Max Lim in Singapore; Editing by Ramthan Hussain)

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