关键词: 青藏高原, 札达盆地, 沉积序列, 藏南拆离系, 伸展盆地

Abstract: Zanda basin, located in the outhwestern Tibetan Plateau, was developed in the inner of Himalayas. The northeastern border of Zanda basin is the Ayila Rij yu thrust, while its northwestern boundary is the Qusum detachment fault. As the controlling structure, the southern Tibetan detachment system (STDS) formed the southwestern boundary of the Zanda basin. In the basin, there developed a series of Neogene strata, which can be divided into two segments. The lower segment is composed of interlayering fluvial and lake deposits, whereas the upper segment consists exclusively of lake sediments. The lower segment can be divided into three sedimentary cyclothems that is marked by the occurrence conglomerate. The lake deposits in the upper segment are almost composed of latilamina mudstone. The dominant tectonics controling the formation of the Zanda basin is extensional, but this basin experienced contraction perpendicular to the orogen at the same time.

Key words: Tibetan Plateau, Zanda basin, sequences of deposits, Southern Tibetan detachment system, extension basin