本文从李四光教授构造体系理论出发综合应用盆地构造解析、平衡地质剖面恢复等方法,探讨了柴达木盆地构造体系特征及其形成的地球动力学背景和地球动力学模型.柴达木盆地受到印度板块、西伯利亚板块、太平洋板块三大板块的共同影响,围绕中部刚性基底周边发育北部祁连山、南部东昆仑山及西部阿尔金山三大构造体系,每个构造体系都是由主要断裂及其伴生的断层相关褶皱组成三排波浪式冲断构造,低序次断层及其相关褶皱呈斜列式分布于其间,整个盆地可以看成三大构造体系叠合的产物,其根本动力学背景是柴达木地块受到南部印度板块向北挤压、北部阿拉善地块的阻挡及东侧华北板块和西侧塔里木地块的侧滑而形成的力偶环境,结合岩石地球化学和平衡地质剖面恢复与分析结果提出盆地发展经历了早-中侏罗世南北向拉张、新生代多次幕式挤压并叠加东西向侧向走滑与旋转、并于第四纪形成现今的构造面貌的发展历史.%Structural analyses and balanced cross-section restoration were jointly used in this paper to investigate the structural system, the tectonic setting and the geodynamic evolution model of the Qaidam basin. Under the common influence of the India plate, the Siberia plate and the Pacific plate, three structural systems developed around the middle rigid block in Qaidam basin, they are the northern Qilian mountain structural system, the southern Kunlun mountain structural system and the western Altun mountain structural system. Each of the structural system contains three thrust structural belts which consists of several main faults and their relevant folds, the sublevel faults and their relevant folds distributed within the thrust structural belts diagonally, and the structural framework of Qaidam basin could be regarded as a superposition of the three great structural system. The basic dynamic setting is that the Qaidam block was compressed by India plate from south to north on the southern margin, resisted by Alxa plate from north to south on the northern margin and sideslip from north China plate on eastern margin and from Tarim plate on western margin. Combining the analysis of balance profile, the basin preliminary dynamic evolution model was established, it is that the Qaidam Basin experienced expansion within the period of Early Jurassic to middle Jurassic and episodic extrusion composited sideslip within the period of Cenozoic, and the structural framework of Qaidam basin was formed within Quaternary.
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