祁连山地区大地构造演化及其性质特征

祁连山地区大地构造演化历经了元古代至早古生代的地槽阶段、晚古生代的地台阶段和中、新生代的地洼阶段。地槽阶段元古代为陆块奠基、成长和扩展时期，早古生代为洋壳化板缘构造活动和陆间碰撞构造作用时期。地台阶段大型沉积盆地发育。地洼阶段以陆内造山－造盆作用和块断推覆构造活动为特征。祁连山地区遭受了三次不同性质的造山作用：元古代未托莱运动的陆块挤压褶皱造山作用、加里东晚期祁连运动的陆间碰撞造山作用和中、新生代的陆内块断造山作用。由上，祁连山及其邻区的构造单位由北至南划分如下：（１）走廊地洼；（２）北祁连地穹；（３）中祁连洼陷；（４）南祁连地穹；（５）柴达木地洼。

GEOTECTONIC EVOLUTION AND ITS CHARACTERISTICS IN QILIANSHAN REGION

In geotectonic evolution Qilianshan region has gone through geosynclinal stage from Proterozoic to earlier Palaeozoic era, platform stage in latter Palaeozoic era and diwa stage in Meso-Cenozoic era,Proterozoic era of geosynclinal stage is the period of foundation , growth and development of landmass. Earlier Palaeozoic era is the periods of plate margin tectonism of crust-oceanization and intercontinental collision tectonism. Large sedimentary basins are developed in the platform stage. Intracontinental orogenesis and basin-making prossesses, and block-faulting nappe tectonism are structural features in the diwa stage.Qilianshan region has been undergone three importent orogenesises of different natures:compression-folding orOgenesis of landmass of Tuolai orogeny in last Proterozoic era, intercontinental collision orogenesis of Qllian otogeny in latter Caledonian period and intracontinental block-faulting orugenesis in Meso-Cenozoic era.From the above it can been seen that tectonic units of Qllianshan and its adjacent regions are divided from north to south into following: Zoulang diwa, North Qilian geodome, Centre Qilian depression, South Qiliang geodome and Qaidam diwa.