柯坪断隆古生代的构造属性及其演化特征

ATTRIBUTE OF PALEOZOIC STRUCTURES AND ITS EVOLUTION CHARACTERISTICS IN KEPING FAULT-UPLIFT

张臣 郑多明 李江海

Zhang Chen Zheng Duoming Li Jianghai

柯坪断隆与巴楚隆起古生代无论在地层系统、岩石组合、古生物及沉积相特征等方面均存在可比性,表明柯坪断隆和巴楚隆起前中生代是连为一体的,同属塔里木盆地的组成部分.中生代柯坪巴楚隆起形成雏形,柯坪地区缺失中生代沉积.新生代由于受欧亚板块南缘地体增生,板块碰撞远距离效应和西南天山地区复活造山影响,在上新世末-更新世初,柯坪断隆沿柯坪塔格沙井子断裂发生强烈挤压形成柯坪逆冲推覆构造带.柯坪断隆构成推覆构造带的上部掩冲构造层,巴楚隆起向西北延伸的部分构成推覆构造带的下伏构造层.地面油气显示不能证明地下已无油气藏存在,不能排除在该区找到大型逆冲断层遮挡圈闭型及牵引背斜圈闭型油气藏的可能.

Stratigraphic sequence,rock assemblage,palaeontologic species and sedimentary facies of Palaeozoic Era in Keping region bear comparison with Bachu region.It indicates that Keping and Bachu uplifts were connected in preMesozoic.They were a part of Tarim Basin.Embryonic form of KepingBachu uplift formed in Mesozoic.Mesozoic sediment was lacunae in Keping region.The region was effected by the accretion of southern margin of Eurasian Plate,far distance effect of plate collision and orogeny of southwest Tianshan Mauntains in Cenozoic.Keping thrust belt was formed along Kepingtage Shajingzi fault.Keping uplift constituted the upper thrust nappe of the thrust belt,the northwest extension part of Bachu uplift constituted the underlying structural layer of the thrust belt.It is possible to find oil and gas pools of thrust fault covered trap type and traction fold type.

10.11743/ogg20010406