基于高精度重磁方法在圈定超基性岩体中的应用研究  

Application of high precision gravity and magnetic method in delineation of ultrabasic rock mass

作　　者：罗睿 区小毅 黎海龙 莫亚军 杨富强 朱国器 LUO Rui;OU Xiaoyi;LI Hailong;MO Yajun;YANG Fuqiang;ZHU Guoqi(Geological Survey Institute of Guangxi Zhuang Autonomous Region,Nanning 530023,Guangxi,China;Geophysical Investigation Institute of Guangxi Zhuang Autonomous Region,Liuzhou 545005,Guangxi,China;China-ASEAN Geoscience Cooperation Center(Nanning),Nanning 530023,Guangxi,China)

机构地区：[1]广西壮族自治区地质调查院,广西南宁530023 [2]广西壮族自治区地球物理勘察院,广西柳州545005 [3]中国-东盟地学合作中心(南宁),广西南宁530023

出　　处：《矿产与地质》2022年第2期265-274,共10页Mineral Resources and Geology

基　　金：广西壮族自治区自然资源厅2018-2019年度找矿突破战略行动地质勘查项目(桂国土资函〔2018〕752号、自然资函〔2019〕647号)共同资助。

摘　　要：桂北元宝山地区是广西重要的多金属成矿区带之一,该地区广泛出露基性—超基性岩体,而基性—超基性岩体与铜、镍、钴、铬等多金属矿产关系十分密切。通过开展1∶1万高精度重磁测量和岩(矿)石物性参数统计,结合研究区成矿地质条件,确定了磁力高、重力高为该铜镍多金属矿区识别基性—超基性岩体的关键标志,重磁综合研究成果表明两者异常具有很好的同源性。利用不同的数据处理和异常分离方法,获取了研究区地球物理场特征,厘清了断裂构造展布格架;深入分析了局部重磁异常特征,并对重点异常25号岩体进行了2.5D人机交互反演拟合计算,获取了岩体的空间形态特征;利用界面反演计算获得了研究区基性—超基性岩体的埋深分布与走向展布规律,提出了研究区内的有利找矿地段。该研究成果对今后利用重磁方法寻找与基性—超基性岩体密切相关的铜镍等多金属矿方面的工作具有重要的指导作用。Yuanbaoshan area in North Guangxi is one of the important polymetallic ore-forming belts in Guangxi.The basic-ultrabasic rock mass is widely exposed in this area,which is closely related to copper,nickel,cobalt and chromium polymetallic mineral resources.In the study area,1∶10000 high-precision magnetic and gravity survey and statistical work of rock(ore)physical parameters are carried out,on the basis of the geological and metallogenic condition of the study area,it is determined that the high magnetic value and high gravity value are the key indicators to identify the basic-ultrabasic rock mass in the copper-nickel polymetallic mining area.The comprehensive gravity and magnetic research result shows that the two anomalies have the good homology.With the different data processing and anomaly separation methods,the characteristics of geophysical field of the study area is obtained,and the distribution framework of fault structure is clarified.The characteristics of local gravity and magnetic anomalies is deeply analyzed,and the 2.5D human-computer interactive inversion fitting calculation is carried out for the key anomaly No.25 rock mass,and the spatial morphological characteristics of the rock mass is obtained.The buried depth distribution and striking distribution of basic-ultrabasic rock mass in the study area are obtained by interface inversion calculation,and the favorable prospecting sections in the study area are pointed out.The research results have an important guiding role for the future work to apply gravity and magnetic methods to explore for copper and nickel polymetallic mineral resources that are closely related to the basic-ultrabasic rock masses.

关 键 词：高精度重磁 超基性岩体 小波分析 界面反演 桂北地区 

分 类 号：P631.1[天文地球—地质矿产勘探] P631.2[天文地球—地质学]