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羌塘盆地东部基底由前石炭纪吉塘岩群组成,沉积盖层为晚古生代一白垩纪地层。其中,中生代海相地层在盆地内分布广泛,沉积体系多样,构造古地理转换频繁。中生代盆地包括南羌塘坳陷、唐古拉山隆起带、北羌塘坳陷等3个构造单元,内部又可以划分出不同时期多个次级凹陷和凸起。盆地的发展和演化既受南、北两侧板块结合带控制,又受盆地内部被分划性断裂带围限的各断块差异性活动约束,依次经历了晚三叠世前陆盆地阶段,“北羌塘”早-中侏罗世伸展裂陷盆地发育阶段,多玛侏罗纪-早白垩世早期被动大陆边缘陆表海盆地发展阶段、晚期前陆盆地阶段,晚白垩世南羌塘山间压陷盆地演化阶段。实质上,该盆地是不同时期原型盆地有序叠加而构成的大型叠复式盆地。
The basement of the eastern Qiangtang Basin consists of the former Carboniferous Jitang Group, and the sedimentary cover is Late Paleozoic-Cretaceous. Among them, the Mesozoic marine strata are widely distributed in the basin, the sedimentary system is diverse, and the tectonic paleogeography is frequently converted. The Mesozoic basin consists of three tectonic units such as the southern Qiangtang depression, the Tanggula uplift and the northern Qiangtang depression, and multiple secondary depressions and protrusions in different periods can be distinguished within the Mesozoic basin. The development and evolution of the basin are not only controlled by the combination of the south and north plates, but also influenced by the different activities of the fault blocks within the basin, which are limited by the dividing fault zone. They experienced successively the stages of the Late Triassic foreland basin, “North Qiangtang” Early-Middle Jurassic extensional rifting basin development stage, the Dama Jurassic-Early Cretaceous passive continental margin continental shelf development stage, the late foreland basin stage, the Late Cretaceous South Qiangtang Mountain Indented basin evolution stage. In essence, the basin is a large-scale superimposed basin composed of an orderly superimposition of prototype basins in different periods.