应用奇异值分解技术提取滇东南锡-钨多金属矿化航磁异常  

Singular Value Decomposition(SVD)used to extract aero-magnetic anomalies related to Sn-W polymetallic mineralization in SE Yunnan,China

作　　者：朱旭 陈永清[1] 赵彬彬 ZHU Xu;CHEN Yongqing;ZHAO Binbin(School of Earth Sciences and Resources,China University of Geosciences,Beijing 100083,China;Sinomine Resource Group Co.,Ltd.,Beijing 100089,China)

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]中矿资源集团有限公司,北京100089

出　　处：《地质通报》2021年第5期764-771,共8页Geological Bulletin of China

基　　金：国家重点研发计划课题《“三联式”数字找矿模型与深部定量成矿预测》(编号:2016YFC0600509);国家自然科学基金项目《深部找矿信息提取与找矿模型建立》(批准号:41672329);《成矿系统自组织临界性与矿床空间定位预测》(批准号:41972312)。

摘　　要：滇东南锡-钨多金属矿集区位于扬子陆块、华夏陆块及印支陆块的交汇处,区内分布一系列与晚白垩世大规模岩浆作用密切相关的锡、钨、铜、银、铅、锌多金属矿床。对滇东南1200000航磁数据化极处理后,应用奇异值分解(SVD)技术提取航磁数据中与锡-钨多金属矿化有关的深部地质结构和地质体特征分量。通过定义不同的滤波器,选择相应的特征分量进行重构,获得反映深部及浅层的地质结构和地质体空间分布的图像。研究表明:①研究区深部存在2种磁性特征的基底,即强磁性基底(哀牢山岩群、大红山岩群和瑶山岩群)和弱磁性基底(昆阳群和猛硐岩群);②与矿化密切相关的花岗岩体显示为环绕负磁异常发育正磁异常,环形正磁异常可能反映了接触交代矿化蚀变带的空间分布;③环绕负磁异常发育正磁异常区域是进一步找寻锡-钨多金属矿床的最佳靶区。The Sn-W polymetallic ore-concentrated area in SE Yunnan is located at the junction of the Cathaysian Massif,Yangtze Massif,and Indo-China Massif,where there are a series of Sn,W,Cu,Ag,Pb,Zn polymetallic deposits closely related to the Late Cretaceous magmatism.The Singular Value Decomposition( SVD) was applied to extract aero-magnetic anomaly components reflecting the deep geological structures and geological bodies associated with the Sn-W polymetallic deposits and mineralized granitic intrusives from the aero-magnetic data of the SE Yunnan district at a scale of 1 ∶200 000. The results show that there are two metamorphic basements,one with strong magnetism( Dahongshan Group,Ailaoshan Group and Yaoshan Group),and the other with weak magnetism( Mengdong Group);granitoids closely related to W-Sn polymetallic mineralization in the study area shows a ring positive magnetic anomaly around a negative magnetic anomaly,which may reflect a contact skarnization zone around a granitic intrusion;and the ring positive magnetic anomalies around negative magnetic anomaly are the best targets for further exploration of Sn-W polymetallic deposits.

关 键 词：奇异值分解(SVD) 航磁致矿异常 锡-钨多金属矿床 花岗岩体 滇东南 

分 类 号：P618.44[天文地球—矿床学] P618.67[天文地球—地质学]