【摘要】 通过柴达木盆地西部茫崖—赛什腾山地表地质、航磁、重力、大地电磁测深和地震资料的综合分析,认为柴达木盆地夹持在昆北地块与赛什腾构造带之间,其中包括柴达木地块与祁连地块南缘2个一级构造单元和昆北地体北缘,柴达木盆地,赛什腾构造带和祁连地块南部的苏干湖盆地等4个二级构造单元。盆地的总体结构表现为东昆仑山和祁连山相向向盆地挤压对冲,盆地中部沉降的构造格局。盆地内部的构造样式以自盆地边缘至中心以此形成背斜构造为显著特征,背斜两翼多发育逆断层,构成“两断夹一隆”的构造格局。挤压应力主要来自南西方向、北东方向起阻挡作用。在两侧造山带的强烈挤压作用下,侏罗纪时期在祁连造山带南缘形成并不典型的前陆盆地,古近纪至新近纪时期则在祁连造山带与昆仑造山带之间形成双侧前陆盆地,第四纪属挤压坳陷盆地。更多还原

【Abstract】 Based on an integrated analysis of the surface geological, aeromagnetic, gravity, MT and seismic data from the area of Mangnai to Serteng Mountains in the western Qaidam basin, the authors think that the Qaidam basin is sandwiched between the North Kunlun block and Serteng tectonic belt, including two first-order tectonic units-the Qaidam block and the southern margin of the Qilian block-and four second-order tectonic units-the northern margin of the North Kunlun block, Qaidam basin, Serteng tectonic belt and Suhai lake basin in the south of the Qilian block. The general structure of the basin is marked by the tectonic framework of compressional ramp of the East Kunlun Mountains and the Qilian Mountains toward and subsidence of the central part of the basin. The tectonic style inside the basin is characterized by occurrence of anticlines from the margins to center of the basin, with two limbs mostly starting from reverse faults, developing a tectonic pattern of two faults sandwiching an uplift. The compressional stress mainly comes from SW, and the NE direction acts as a resistance. Under the strong compression from the orogenic belts on both sides, in the Jurassic an atypical foreland basin developed on the southern margin of the Qilian orogenic belt; in the Tertiary, a two-side foreland basin formed between the Qilian orogen and Kunlun orogen; in the Quaternary, the Qaidam basin is a compressional, downwarped basin.更多还原