格尔木－额济纳旗地学断面地球动力学模型初探

PRELIMINARY GEODYNAMIC MODEL OF GOLMUD PIIN QI GEOSCIENCE TRANSECT ─EJIN QI GEOSCIENCE TRANSECT

概述格尔木－额济纳旗地学断面研究的地学环境、调查研究内容和初步建立的地球动力学模型．印度板块向北运动为主、西伯利亚板块向南楔入为辅的双向挤压环境是大陆岩石圈最新变形的背景．下地壳的挤压和上地壳的逆冲走滑以及滞后伸展构造组成了岩石图变形的力学系统．

The Golmud─Ejin Qi Geoscience Transect (GET) is located in the northwestern part of China. It starts from the northern margin of the Kunlun Mts., and crosses northerly the Qaidam Basin, Har Lake, Qilian Mis., Hexi Corridor and Beishan, and ends in Ejin Qi near the Sino─Mongolian border. The transect is about 900 km long in all.The article describes the tectonic framework, gives a omprehensive analysis of geophysical field survey data and a preliminary geodynamic model of the geoscience transect from Golmud to Ejin Qi.The model expresses the mechanical state of double compression that consists of the major northward compression of the indian plate and the minor southward compression of the Siberian Plate. The convergent force of the plates results from the uneven flows in the mantle. The compression occurs mainly in the middle and lower crust,in the upper crust thrusting and strike-slipping followed by extension are dominant. These constitute the mechanical system of the newest deformation of the lithosphere.