【摘要】 2017年河套盆地临河坳陷油气勘探取得重要发现,基于区域中生代以来大地构造演化系统梳理,以钻井与地震对照、研究区与邻近盆地类比为研究方法,划分河套盆地临河坳陷南部吉兰泰凹陷中生代构造层,并绘制其分布范围,探讨其赋存特征与意义。结果表明:研究区中生界除三叠系外发育齐全,厚度巨大,且白垩系自上而下可细分为K₁^Ⅰ、K₁^Ⅱ和K₁^Ⅲ三个构造层;除K₁^Ⅰ构造层全区广覆式发育外,其它构造层呈楔状—缓楔状,长轴沿主控断裂NNE向延伸;研究区自中生代以来盆地性质经历了早中侏罗世断陷、早白垩世早期断陷、早白垩世中期断拗转换和早白垩世晚期拗陷的演化过程;F₃和F₇断层之间的K₁^Ⅱ和K₁^Ⅲ构造层、F₇断层东部的J构造层均具良好的油气勘探前景。更多还原

【Abstract】 Significant discoveries of petroleum exploration have been achieved in 2017 in the Linhe Depression,Hetao Basin.Based on a literature review of the tectonic evolution of the study area since the Mesozoic,combined methods of well-seismic comparison and basin analogy,the Mesozoic tectostratigraphic units of Jilantai Sag have been determined,and their occurrence and significance have also been studied.The results show that,except for the Triassic,the Mesozoic strata were well developed in the study area.Particularly,the Cretaceous strata can be further divided into three tectostratigraphic units,i.e.,K₁^Ⅰ、K₁^Ⅱ and K₁^Ⅲ;The K₁^Ⅰ is characterized by abroad sedimentation unit covering the whole study area,while the other tectostratigraphic units are wedge-shaped with major axes aligning along the NNE main faults;The Mesozoic basin type of the Jilantai Sag have experienced rift stage during the Early-Middle Jurassic,rift stage during the early Early Cretaceous,transitional stage from rift to depression during the middle Early Cretaceous,depression stage during the late Early Cretaceous;The strata of the K₁^Ⅱ and K₁^Ⅲ tectostratigraphic units located between the faults F₃ and F₇,and the J tectostratigraphic unit located in the east of fault F₇ show great potential of petroleum exploration.更多还原