重磁电综合地球物理探测河套盆地深部结构

GRAVITY,MAGNETIC AND ELECTRIC COMPREHENSIVE GEOPHYSICAL PROSPECTING FOR DEEP STRUCTURES IN HETAO BASIN

从地球物理的角度出发,利用重力、磁法及电法勘探对河套盆地第四系深覆盖区展开深入研究,对河套断陷带南北边界断裂——鄂尔多斯北界断裂、色尔腾山前断裂的性质,河套盆地第四纪沉积物特征及厚度,河套沉积基底构造的探测进行了大量研究工作,并利用电法剖面对该区第四纪含水层分布规律进行了初步研究。通过重磁联合反演、天然地震数据,分析并推断了研究区由南向北的4条隐伏断层F1—F4及狼山—色尔腾山前大断裂F5,同时揭露了该区结晶基底的起伏及埋深,研究区南部基底深度2.5-4.2 km,北部中心基底最大埋深可达6 km,北部色尔腾山前断裂带迅速升至0-1 km。

The gravity,magnetic,and electrical methods have been used to reveal the structure developed in the deep covered area of the Hetao Basin. We have carried out a lot of research on the characteristics of the northern and southern boundary faults,the features and thickness of Quaternary sediments and the structures developed in the basement of the Hetao Basin. A preliminary study on the distribution of Quaternary aquifer in this area was made by using electrical resistivity method.The joint inversion results of gravity and magnetic data,and earthquake data have been analyzed.And four concealed fault F1 to F4from south to north and Langshan-Seertengshan piedmont fault F5 have been revealed. The fluctuation and buried depth of the crystalline basement in the area have been revealed. Depth of the basement in the southern part of the study area is about 2. 5 ~ 4. 2 km,and which in the northern part is up to 6 km. North Adjacent to the Seertengshan piedmont fault,the basement rock has been uplifted to about 0—1 km.