AMT法在四川广元宝轮地区中浅部地质调查中的应用

发布时间：2018-04-28 10:19

本文选题：音频大地电磁法 + 中浅部勘探　；参考：《地质学报》2017年03期

【摘要】：音频大地电磁法(AMT)作为一种中浅部勘探技术,相较于传统直流电法,具有工作效率高、不受高阻层屏蔽和对低阻层分辨率较高等优点。本文基于四川广元宝轮地区深部地质调查的需求,依托研究区物性测试成果和地质构造背景,建立包含逆冲断层、飞来峰构造和岩体构造的典型地电模型,使用正演软件开展大地电磁正演模拟,分析了方法的有效性;然后在垂直构造走向的方向开展AMT勘探工作,采用NLCG反演技术获取高精度二维电性剖面,结合研究区物性测试成果和地表地质调查成果,开展地质地球物理综合解释并建立沿剖面方向的地质模型,查明了梨树坝断层的深部展布特征、飞来峰构造及主要地质体的深部边界与规模等地质问题。研究结果表明:音频大地电磁法是开展中浅部地质调查的有效手段,能较好分辨出中浅部具有电性差异的不同规模地质要素。
[Abstract]:Audio frequency magnetotelluric method (AMT), as a medium and shallow exploration technology, has the advantages of high working efficiency, no shielding from high resistance layer and high resolution to low resistivity layer, compared with the traditional DC method. Based on the requirement of deep geological survey in Guangyuan Baolun area, Sichuan province, a typical geoelectric model including thrust fault, Feilai peak structure and rock mass structure is established based on the physical property test results and geological structure background of the study area. Magnetotelluric forward modeling is carried out using forward modeling software, and the validity of the method is analyzed, then AMT exploration is carried out in the direction of vertical structural strike, and the high precision two-dimensional electrical profile is obtained by using NLCG inversion technique. Combined with the results of physical property test and surface geological survey in the study area, the geological geophysical comprehensive interpretation and the geological model along the section are established, and the deep distribution characteristics of the Lishuba fault are found out. Feilefeng structure and deep boundary and scale of main geological bodies and other geological problems. The results show that the Audio magnetotelluric method is an effective means to carry out the middle and shallow geological survey, and it can distinguish the different scale geological elements with electrical difference in the middle and shallow areas.
【作者单位】：成都理工大学地球探测与信息技术教育部重点实验室;中国地质大学(北京);宁夏回族自治区地质矿产勘查开发局;
【基金】：中国地质调查局项目“龙门山构造带深部地质调查”(编号1212011220263) 国家自然科学基金项目(编号41274078)资助成果
【分类号】：P631.325

【相似文献】