基于综合地球物理资料研究余下—铁炉子断裂带及邻区深部构造特征及其地质意义  

Geological significance and deep tectonic features of the Yuxia-Tieluzi Fault zone and adjacent area based on comprehensive geophysical data

作　　者：许文强 袁炳强 姚长利[1,2] XU WenQiang;YUAN BingQiang;YAO ChangLi(School of Geophysics and Information Technology,China University of Geosciences,Beijing 100083,China;Key Laboratory of Geo-detection(China University of Geosciences,Beijing),Ministry of Education,Beijing 100083,China;School of Earth Sciences and Engineering,Xi'an Shiyou University,Xi'an 710065,China)

机构地区：[1]中国地质大学地球物理与信息技术学院,北京100083 [2]地下信息探测技术与仪器教育部重点实验室(中国地质大学,北京),北京100083 [3]西安石油大学地球科学与工程学院,西安710065

出　　处：《地球物理学进展》2021年第3期977-992,共16页Progress in Geophysics

基　　金：中国地质调查局资源调查与评价项目(12120113040300-03,[2016]03012-06)资助。

摘　　要：通过整理、收集研究区近年来新测地球物理数据,结合钻井和地质等资料以及前人研究成果,利用新方法处理了研究区重磁数据,讨论了余下—铁炉子断裂带及邻区重磁异常特征及地质意义,推断了研究区断裂构造,结合地震和电法对研究区构造特征进行了定性和定量分析,并探讨了该断裂带对研究区的地质意义.结果表明,余下—铁炉子断裂带为近EW向复合型岩石圈断裂带,受多期构造演化和构造应力影响,其埋深较大、切割深度较大,断裂性质呈多期次性、复杂性、多样性和活动性,在渭河盆地和秦岭地块的断裂性质不一.该断裂带在渭河盆地内呈隐伏深大断裂带,断裂带及邻区深部构造稳定性较差,更新世以来深部构造仍在活动,同时结合该断裂带周围深、浅部地质构造的分异性和不稳定性说明了该区有孕育发生中小、中强地震的构造条件,推测存在中小地震发生的可能性.余下—铁炉子活动断裂带具区域性控(导)岩(矿)作用,控制了盆地南缘的形成和发展,断裂带周围及与其他断裂的交汇处附近是该区"一热两气"和矿藏等资源主要分布区.The new geophysical measurement data was collected and neatened in the study area in recent years. Combined with drilling, geological data and previous research results. The gravity and magnetic data are processed by new methods. The characteristics and geological significance of gravity and magnetic anomalies are analyzed in the Yuxia-Tieluzi Fault(YTF)zone and adjacent area. The faults were inferred. The tectonic features of the study area were qualitatively and quantitatively analyzed by seismic and electrical data. And the geological significance of the YTF zone to the study area was discussed. The results indicate that the YTF zone is a near-EW composite lithosphere fault zone, which was affected by multi-stage tectonic evolution and tectonic stress. It has large burial depth and large cutting depth. The properties of faults are multi-stage, complex, diverse and active, and there are different fault properties in Weihe Basin and Qinling Block.The YTF zone is a hidden deep fault zone in the Weihe Basin. The deep tectonic stability of the fault zone and adjacent areas is relatively poor. Deep structures are still active since the Pleistocene. At the same time, the differentiation and the instability of geological structures in deep and shallow around the fault zone indicates that there are tectonic conditions for the occurrence of small and medium and strong earthquakes in this area, and the possibility of small and medium earthquakes is speculated. The YTF active zone has regional control(guide) rock(mine) function, which controls the formation and development of the southern margin of the Weihe Basin. And around the fault zone and near the intersection with other faults are the main distribution areas of resources such as"Geothermal, Gas soluble in geothermal water, soluble helium gas"and mineral deposits.

关 键 词：综合地球物理 重磁异常 构造特征 余下—铁炉子断裂带 渭河盆地 

分 类 号：P541[天文地球—构造地质学] P631[天文地球—地质学]