China Petroleum & Chemical Corp., the world’s biggest refiner, is weighing a takeover of beleaguered Kurdish oil producer Gulf Keystone Petroleum Ltd., people familiar with the matter said. The state-owned oil giant, known as Sinopec, is working with advisers and has made an approach to Gulf Keystone, said the people, who asked not to be named because the deliberations are private. The company may also attract other bidders, they said. No final decisions have been made and any talks may not lead to a deal, the people said. Representatives for Gulf Keystone and Sinopec declined to comment. Gulf Keystone rose 13 percent to 143 pence in London trading at 10:42 a.m. Tuesday, giving the company a market value of 328.1 million pounds ($416.7 million). The shares earlier rose as much as 16 percent, the biggest intraday gain since October. Gulf Keystone, which operates in the Kurdish region of Iraq, […]