China Petroleum & Chemical Corp. (386) , Asia ’s biggest refiner, reported an 8 percent gain in first-half oil and gas production as overseas output doubled. Output rose to 237 million barrels in the six months ended June 30, the Beijing-based company known as Sinopec said in a statement yesterday after the close of trade. Production rose faster than the 3.8 percent increase a year earlier. Overseas crude oil production increased to 23.7 million barrels in the first-half, Sinopec said. Output rose after the refiner bought foreign assets from its state-owned parent last year, according to Laban Yu, a Hong Kong-based analyst at Jefferies Group LLC. “The increase came totally from the acquisition of the parent’s assets last year,” Yu said by phone. “Its organic growth was flat in the first-half, although the near 10 percent increase in natural gas could be considered positive, compared with the around 7 […]