塔里木盆地北部白垩系—古近系不同段、带沉积体系比较研究

Comparative of Different Segmentations and Zones During Cretaceous and Paleogene in North Tarim Basin

塔里木盆地北部库车坳陷—塔北地区白垩系—古近系发育有冲(洪)积扇、终端扇、三角洲(扇三角洲、辫状河三角洲、正常三角洲)、湖泊、滨岸海滩、潮坪—潟湖等多种沉积相类型。研究区南、北带及东、中、西段在不同沉积演化时期发育的岩性组合、沉积相类型及沉积相平面展布规模方面也有明显差异,北带主体为粗碎屑沉积,发育扇三角洲沉积;南带沉积物粒级相对较细,主体发育辫状河三角洲,这种差异主要受当时古构造位置、古地形坡度、沉积物源远近及古气候控制。

There are many sedimentary facies, which are alluvial fans, terminal fans, fan-delta, braided-delta, meandering-delta, lacustrine facies,lagoon and beach facies,in Cretaceous and Paleogene, Kuche Depression-Tabei area, northern Tarim Basin. The lithology assemblages and sedimentary facies are different in north and south zone, also in the east, middle and west segmentation. The north zones are made up of coarse clastics, which are mainly fan-delta. The south zones are composed of middle and fine clastics,which are mainly braided-delta. The differences are controlled by palaeo-structure, palaeo-topographical gradient, palaeoclimate and the dlistance to provenance.