Abstract:

he south area of Songliao Basin and west area of Liaoning tretch across several geotectonic units such as XingmengJihei orogen, North China Platform, and increased convergent plate boundary in north border of North China Platform. In Liaoxi basinandrange province, Songliao Basin province, and Liaobei basin province, a series of different types of basins in Late Triassic, MiddleLate Jurassic, Cretaceous basins were developed under the control of different types of basements and regional faults. Basins in different periods evolved discontinuously, and directions of these basins are very obvious. Source rocks in Triassic are not well,and two suits of coalbearing strata in Lower Jurassic and Lower Cretaceous are main source rocks. The Beipiao Formation in Jurassic is important source rock in the ChaoyangBeipiao basins etc. The development of Cretaceous source rocks are better, there also develop potential source rocks in Yixian Formation except three sets of source rocks, Jiufutang Formation, Shahai Formation and Fuxin Formation. The basin hydrocarbon assessment indicated that there grow four different grades of hydrocarbon basins in Liaobei basin, the exploration prospects of the Lujiapu fault depression, Qianjiadian fault depression, Changtu fault depression, Manghan fault depression are best, and FuxinYixian basin, ChaoyangBeipiao basin have a certain exploration prospect in Liaoxi area.

Key words: Songnan Liaoxi area, Mesozoic, sedimentation basin, source rock, hydrocarbon assessment, exploration prospect