S-A多重分形法在地球化学异常圈定中的对比应用——以甘肃文康地区为例  

Comparative Application of S-A Multifractal Method to Geochemical Anomaly Delineation:A Case Study of the Wenkang Area,Gansu Province

作　　者：牛旭刚 周宏[3] 张文纲 牛永杰 郭东宝 丁国林[1,2] 王茂 NIU Xugang;ZHOU Hong;ZHANG Wengang;NIU Yongjie;GUO Dongbao;DING Guolin;WANG Mao(Key Laboratory of Strategic Mineral Resources in the Upper Yellow River,Ministry of Natural Resources,Lanzhou,Gansu 730000;Lanzhou Institute of Mineral Exploration,Bureau of Nonferrous Metals Geological Exploration of Gansu Province,Lanzhou,Gansu 730000;Gansu Nonferrous Metal Geological Exploration Bureau,Lanzhou,Gansu 730000)

机构地区：[1]自然资源部黄河上游战略性矿产资源重点实验室,甘肃兰州730000 [2]甘肃省有色金属地质勘查局兰州矿产勘查院,甘肃兰州730000 [3]甘肃省有色金属地质勘查局,甘肃兰州730000

出　　处：《地质与勘探》2023年第4期817-827,共11页Geology and Exploration

基　　金：中国地质调查局“甘肃省文康金矿带岸门口及外围地区矿产地质调查”项目(编号:12120113048000)资助。

摘　　要：通过对甘肃省陇南文康地区的地质背景分析,采用区域1∶5万水系沉积物测量的17种常量元素含量数据,分别运用传统统计学方法、S-A (能谱密度-累计面积)多重分形滤波法,确定成矿元素(以Au为例)异常下限值,圈定化探异常。结果表明,与传统方法相比,S-A多重分形法所圈定的异常面积小、数量多,传统统计法圈定的面积较大;两种方法圈定的异常展布方向基本一致,与研究区内已知的矿点吻合度高。本次研究认为S-A多重分形法所圈定的异常基本位于传统方法所圈定异常的内带之中,重点突出,与矿床空间位置对应关系较好,便于野外开展工作。同时在传统异常周边提取了部分低背景区的弱异常,这些弱异常可作为下一步找矿工作的新靶区。Through the analysis of the geological background of the Wenkang area in Longnan,Gansu Province,by using the content of 17 major elements obtained from regional 1:50000 stream sediment measurements,the traditional statistical method and S-A(energy spectral density cumulative area)multifractal filtering method were used to determine the lower limit of the anomaly of ore-forming elements(taking Au as an example)and delineate geochemical anomalies.The results show that compared with traditional methods,the anomalies delineated by S-A multifractal method have a smaller area and larger quantity,while the areas delineated by traditional statistical methods are larger.The anomaly distribution directions delineated by the two methods are basically consistent,and agree well with the known mineral occurrences in the study area.This study suggests that the anomalies delineated by the S-A multifractal method are mostly located within the inner zone of the anomalies delineated by traditional methods,with a prominent focus and a good correspondence with the spatial location of the deposits,making it convenient for field work.In addition,weak anomalies in some low background areas were extracted around traditional anomalies,which can serve as new targets for future mineral exploration work.

关 键 词：地球化学异常 S-A多重分形法 地质统计学 因子分析 异常圈定 文康地区 甘肃 

分 类 号：P632[天文地球—地质矿产勘探] P595[天文地球—地质学] O14.4[理学—数学]