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

关键词:  塔西南地区  中亚盆地  沉积构造演化  沉积体系  沉积序列对比  白垩系  古近系

Key words:  southwestern Tarim Basin  central Asia basin  sedimentary-tectonic evolution  depositional system  correlation of depositional sequences  Cretaceous  Palaeogene

摘要:

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。

Abstract:

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.