Chinese energy majors are seeking out more overseas investment opportunities in 2012, with a peculiar focus on resource-rich Australia, North and South America.

China Petroleum & Chemical Corp. (Sinopec, 600028.SH), China's second-largest oil company, has been on a global shopping spree over the past year, buying a stake in Chevron Corp.'s deepwater Indonesian project in October, agreeing to form an Australian LNG joint venture and a deal to buy into a Brazilian oil services group, and the $2.1 billion acquisition of Canada's Daylight Energy Ltd.

PetroChina Co. Ltd. (601857.SH, 0857.HK) said last week that it would buy the portion of the Mackay River oil sands projects it did not own from Canadian partner Athabasca Oil Sands Corp., making it the first large-scale development in the region to be wholly controlled by a Chinese state-owned group.

Chinese state-owned enterprises' interest in foreign oil and gas resources gained speed in 2005, when it became clear overseas resources would be required to fuel China’s rapid economic development.

Emerging markets have proved an easier target for overseas deals than developed ones. CNOOC Ltd.’s (0883.HK) failed bid to buy Unocal Oil Company in 2005, which collapsed in the face of U.S. political opposition, was interpreted at the time as sign of the challenges in entering developed countries.

But the U.S. is gradually becoming more open to Chinese investments in its energy sector, typically unconventional assets, as can be seen in multiple successful partnerships and investments including PetroChina’s $1.7 billion-dollar investment in Chesapeake's shale properties.

In January, Sinopec entered into a $2.2 billion-dollar joint venture with U.S.-based Devon Energy Corp. to develop shale gas in the U.S. The deal entitled Sinopec to one-third of the equity stake in five gas fields.

Sinopec’s decisions have been guided by the steady hand of chairman Fu Chengyu, who was a former top decision-maker at CNOOC.

Fu said in an interview with Century Weekly that the best opportunity arrives in times of economic crisis.

"When the U.S. economy was fairing well in 2005, they objected CNOOC's bid for Unocal, which supplies less than 1 percent of America's total oil and gas volume. But they approved of many other deals after the financial crisis hit its economy," Fu said.

However, investing in energy assets, especially in emerging markets, can be a tricky business. The uprising in Libya last year was an extreme example of what can go wrong; the decision by the government of Argentina last week to nationalize local oil company YPF, controlled by Spain's Repsol, is more indicative of what could happen.

Argentine president Cristina Fernandez hopes to seize control of YPF. If successful, she will have scuppered years of planning by Sinopec to buy the South American company. The Chinese energy giant had held talks with Repsol to buy its controlling 57 percent stake in YPF and had inked a reached a non-binding than $15 billion agreement to do so, according to Reuters.

"It's too hairy for any Chinese major to put in that much money, unless there is a special relationship with the Argentinian government, which I doubt," a mergers and acquisitions banker told Reuters.