河套弧形地堑系构造特征和演化机制及其油气勘探

STRUCTU RAL CHARA CTERISTICS,MECHANISM OF EVOLUTION AND PETROLEUM PROSPECTING OF HETAO GRABEN SYSTEM

河套弧形地堑系是新生代断陷盆地,断裂构造发育,以正断层为主,并兼有平移性质。该区中生代受控于近南北向的左旋剪切作用,新生代受控于南北向的右旋剪切作用。地堑系具有油气生成、聚集和保存的构造耳境,其中巴音浩特坳陷和吉兰泰坳陷的石炭-二叠系和侏罗-白垩系及临河坳陷的下白垩统和渐新统是有勘探前景的层系。

Hetao arcuate graben system is a Cenozoi(?) rift basin.There are mainly normal faults with some shearing character in this basin.This area was contr- olled by the left-rotational stress trending SN in Mesozoic era,and by the de- xtro-rotational stress trending SN in Cenozoic era.There are favorable tecto- nic conditions for generation,accumulation,preservation of oil and gas in the basin.Carboniferous-Permian and Jurassic-Cretaceous in Bayinhaote graben and Jilatai graben,and Cretaceous and Oligocene in the wast part of Linhe graben are the prospective strata.