塔里木盆地西南部—西昆仑地区构造电性特征与A型俯冲模式

TECTONIC ELECTRICAL CHARACTERISTICS AND A-MODEL SUBDUCTING PATTERNS OF SOUTHWEST TARIM BASIN-WEST KUNLUN AREA

鲁新便 石彦 田春来

Lu Xinbian Shi Yan Tian Qulai

地矿部西北石油地质局第一物探大队 乌鲁木齐 830011

No.1 Geophysical Prospecting Party, North-west Bureau of Petroleum Geology, MGMR

本文依据联接塔里木盆地西南部和西昆仑褶皱带的两条大地电磁测深剖面解释结果,研究和分析了测线所经地区的岩石圈地电结构特征。指出塔里木盆地西南缘发育规模较大的逆掩推覆构造带,推覆体宽度约40km,由南向北的推覆距离达20km以上。并依据电性资料划分了构造单元,探讨了各单元的构造接触关系。最后通过对该区均衡重力异常特征、地震活动和岩石圈内部低阻层比面地表陆内变形的综合分析,研究和建立了塔里木西南部和西昆仑之间的陆内俯冲模式,提出该区广泛存在的推覆构造与地壳深部存在陆内俯冲作用有关的观点和认识。

Based on the explanatory results of two magnetotelluric sounding profiles which connect the folded belts of Southwest Tarim Basin with West Kunlun. the geoelectric tectonic characteristics of lithosphere along the measuring areas are studied and analysed. It is pointed out that the width of nappe is about 40km and the nappe distance from south to north is more than 20km within the larger-scale developed overthrust nappe tectonic belt on the southwest edge of Tarim Basin. Moreover, tectonic units are divided and the tectonic contact relations of each unit are approached according to electrical data. Lastly, by means of comprehensive analyses on the characteristics of isostatic gravity anomaly, seismic activity etc. of this area, the intracontinental subducting patterns between Southwest Tarim Basin and West Kunlun are studied and established, and the viewpoint and cognition that the nappe tectonics extensively present in the area relate to intracontinental sub-duction existing in deep earth crust are suggested.

国家重点科技攻关项目85-101-02-01-03专题的部分研究成果

https://doi.org/10.11781/sysydz199503238