关键词: 柴达木盆地, 北, 前陆盆地, 构造格局, 构造演化, 冲断层, 推覆体

Abstract: The northern margin area of Qaidam basin is divided into four structural zones, from north toward south, the Qilianshan fault-folding mountain system, the thrust-overthrust structural zone, the foreland decollement-detachment zone and low strain zone in the foreland basin. For all the fault-folding structural zones, their forming time shows a tendency becoming younger and younger southward. The overall configuration shows the north boundary of foreland basin is at Qaidam basin's northern margin and southern Qilian fault-folding mountain system are enhanced and fixed during the Indo-China cycle and Indo-China movement by the end of Triassic,so determining the basic development configuration of foreland basin in the foremont area. The Yanshan cycle and Yanshan movement by the end of Cretaceous,exerted very intensive influence on the thrust-overthrust structural zone. It makes the center of subsidence and deposition shifted into the basin and formed some structural trapment preliminarily. During the Himalayan cycle period two tectonic movements occurred in Qaidam basin both of bigger scale. The movement that occurred by the end of Oligocene shows strongest influence on Qaidam northern marginal foreland decollement-detachment zone,not only pushing the center of subsidence-deposition further into the basin but also forming structural trap related in this zone. All the fault-folding tectonic zones at the basin's northern margin area are basically fixed by one most intensive structural movement at the end of Pliocene.

Key words: Qaidam basin, north, foreland basin, tectonic configuration, tectonic evolution, thrust fault, over-thrust body