The northwestern part of China is one of the country's most prospective onshore oil and gas regions, where many large sedimentary basins are located (i.e., the Zhungeer, Talimu, Tulufan, Chaidamu, and West Gansu). In all these basins, both Mesozoic-Cenozoic sediments of continental origin and Paleozoic sediments of marine origin were deposited, totaling more than 10,000 m (33,000 ft) in thickness. As the rocks are mostly unmetamorphosed, they are highly prospective targets for oil and gas exploration. Tectonically, the northwest basins are widely different from others in China, most of which are formed by tension and normal faults that tend to produce fault structure zones or rollover anticlines. In the northwest, the basins are mostly formed by compression in which thrus faults and reverse faults that develop into many structure zones and local structures occur. The rows of structural zones at the piedmont of Tianshan, Kunlunshan, Alkinshan, and Nanshan mountains are good objectives for oil exploration.

Although most of the reservoir rocks in northwest China are of Mesozoic age, with only a small amount of Cenozoic strata, Palezoic rocks are also considered as exploration objectives. It is anticipated that varied types of oil pools, typical structural oil pools, or large-scale stratigraphic accumulations may be found in these Paleozoic rocks.

Many oil and gas fields have already been discovered in these basins and are in production. They may constitute an important oil production base in China.

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