OOPS- Error- just read the news report, the company bought was Daylight, in Canada, not U.S. I misheard the TV news bite. Oil and shale gas reserves.
The Bloomberg report says Chinese companies have bought $30 billion of Canadian assets in the past 5 years to meet energy demands in China, and to obtain access to drilling methods.

China has an est. 1,275 trillion feet of technically recoverable shale gas, more than the estimated reserves in the United States and Canada combined, according to an April report by the U.S. Energy Information Administration.
http://www.bloomberg.com/news/2011-10-09/sinopec-agrees-to-buy-daylight-energy-for-2-1-billion-to-meet-fuel-demand.html