Sinochem Group announced on Jan. 31 that it will spend $1.7 billion for a 40 percent stake of 207,000 acres of the Wolfcamp shale-oil field in Texas from American Pioneer Natural Resources (NYSE: PXD).

According to the contract, Sinochem will pay $500 million in cash for the shale-oil development rights in an 82,800-acre area. The remaining $1.2 billion will be paid in the form of drilling and facility costs.

The business delivery is expected to be complete in the second quarter of 2013.

It's the first time Sinochem has purchased an overseas shale-oil field, but the fourth deal to be conducted by a Chinese oil company.

Data from Bloomberg News reveals that Chinese companies have announced acquisitions valued at $17.9 billion for North American oil and gas companies in the past twelve years.

The state-owned Sinochem Group is the fourth largest oil company in China after CNOOC, Sinopec and PetroChina and has seldom worked in the shale gas industry.

By comparison, PetroChina has gone the furthest in the shale gas industry with Oil and Gas Field Company, a subsidiary which has a production and sales capacity of over 10 million m3 shale gas. Meanwhile, Sinopec has announced plans to cooperate with American ConocoPhillips Company (NYSE: COP) in oil-shale development and last December CNOOC obtained its first oil-shale exploration project in Anhui province as well.

With shortages in oil resources, the structure of energy resources are in transition, leading to CNOOC, PetroChina and Sinopec all seeking the next promising energy source to keep their leading positions and hence stepping into the shale-oil sector.

However, for Sinochem, owning little of China's oil fields, it has not performed very well in the oil industry.

PetroChina and Sinopec both have abundant sales channels in the domestic downstream market, which happens to be the weak point of Sinochem. So Sinochem should firstly expand its sales outlets in downstream market, said Wan Xuezhi, research in energy sector at ChinaVenture.