塔里木盆地西南地区与相邻中亚盆地白垩系——古近系沉积演化对比

Correlation of Cretaceous—Palaeogene sedimentary evolution in southwestern Tarim Basin and adjacent central Asia basins

塔西南地区位于新特提斯洋北缘,与中亚地区的阿莱盆地、费尔干纳盆地和塔吉克盆地连通。本文综合前人构造研究成果及塔西南地区最新钻井、野外露头资料,发现塔西南地区白垩系—古近系经历了陆相-海相-陆相的沉积演化过程。下白垩统及始新统上部—渐新统发育陆相沉积,为冲积扇-扇三角洲-湖泊沉积体系;上白垩统—始新统下部发育海相沉积,识别出蒸发台地、开阔台地、局限台地和有障壁海岸等沉积相。中亚地区白垩系—古近系受新特提斯洋海侵-海退过程的影响,整体与塔西南地区同步,也经历了陆相-海相-陆相的沉积演化过程。

The southwestern region of the Tarim Basin was located on the northern margin of the Neo-Tethys,and linked with the Alay Basin,Fergana basin and Tajiki Basin in central Asia during the Cretaceous—Palaeogene. In the light of the previous results,and current data of drilling,logging and outcrops,the Cretaceous—Palaeogene strata in the southwestern region of the Tarim Basin has witnessed continental-marine-continental evolution. The continental deposits occur in the Lower Cretaceous strata,the upper part of the Eocene strata and Oligocene strata,and represent the alluvial fan-fan delta-lake deposits. The marine deposits occur in the Upper Cretaceous-lower Eocene strata deposited in the evaporate platform, open platform, restricted platform and barrier coastal environments. Influenced by the transgression and regression of the Neo-Tethys,the Cretaceous—Palaeogene strata in central Asia region had also experienced the same evolution with those in the southwestern region of the Tarim Basin in China.