基于重磁资料在山东齐河——禹城探获矽卡岩型富铁矿:对超深覆盖区找矿的启示  

Discovery of skarn iron-rich deposit based on gravity and magnetic data in the Qihe-Yucheng,Shandong Province:Enlightenment to prospecting of the super-deep coverage area

作　　者：王润生 郝兴中[3] 胡蕾 陈宏杰 刘辉 陈方博 于露 刘伟 方磊 康一鸣 WANG Runsheng;HAO Xingzhong;HU Lei;CHEN Hongjie;LIU Hui;CHEN Fangbo;YU Lu;LIUWei;FANG Lei;KANG Yiming(Shandong Geophysical and Geochemical Exploration Institute,Jinan 250013,Shangdong,China;Shandong Geological Exploration Engineering Technology Research Center,Jinan 250013,Shangdong,China;Shandong Institute of Geological Survey,Jinan 250014,Shangdong,China;School of Geophysics and Information Technology,China University of Geosciences(Beijing),Beijing 100083,China;Geophysical Survey Center,China Geological Survey,Langfang 065000,Hebei,China)

机构地区：[1]山东省物化探勘查院,山东济南250013 [2]山东省地质勘查工程技术研究中心,山东济南250013 [3]山东省地质调查院,山东济南250014 [4]中国地质大学(北京)地球物理与信息技术学院,北京100083 [5]中国地质调查局地球物理调查中心,河北廊坊065000

出　　处：《中国地质》2023年第2期331-346,共16页Geology in China

基　　金：中国地质调查局项目(DD2016005223,DD20190166);山东省重大科技创新工程项目(2018CXGC1601)联合资助。

摘　　要：【研究目的】山东齐河—禹城矿集区内分布近南北向且具有一定同源特征的重磁异常带,前期陆续在北部李屯、南部大张重磁异常内揭露到厚大的矽卡岩型富铁矿床,铁矿勘查工作取得较大进展,但矿集区中部潘店异常区被超深的新生界覆盖,异常规模小、强度弱,深部铁矿体的地球物理信息被极大弱化,且矿致磁异常又一定程度被大规模的磁性岩体异常所掩盖,识别和提取难度较大,因此一直未取得找矿突破。【研究方法】本文充分结合相邻矿区重磁勘查的成功找矿经验,由已知到未知,对潘店重磁异常进行平面剖析和剖面定量反演,实现了研究区构造格架划分、成矿地质体圈定、异常剖析研究及2.5D联合反演的全流程解译。【研究结果】基于高精度重磁资料的综合研究,获取了超深覆盖层下的深部找矿信息,最终在齐河—禹城矿集区中部实现了矽卡岩型富铁矿的找矿新突破,使矿集区内3处重磁异常得以紧密关联,并证实了大张、潘店、李屯三处铁矿床处于同一近南北向的中性岩浆岩带内,开辟了齐河—禹城矿集区内又一处重要的找矿新空间。【结论】本次找矿成果为后续进一步开展超深覆盖层下的深部找矿工作提供了重要参考和指示,同时表明齐河—禹城矿集区内具有广阔的矽卡岩型富铁矿找矿前景。This paper is the result of mineral exploration engineering.[Objective]A nearly N-S trending gravity and magnetic anomaly zone with certain homologous characteristics was identified in the Qihe-Yuchen ore concentration area,Shandong Province.In the early stage,thick skarn iron-rich deposits were successively revealed in the northern Litun and southern Dazhang gravity and magnetic anomalies,and great progress has been made in iron ore exploration.However,the Pandian anomaly area,the central part of the ore concentration area is covered by ultra deep Cenozoic,with small scale and weak intensity,while the geophysical information of deep iron ore body is greatly weakened,and the ore-induced magnetic anomaly is covered by the large-scale magnetic anomaly of diorite to a certain extent,which makes it difficult to identify and extract.Therefore,no prospecting breakthrough has been made in the Pandian anomaly.[Methods]This article fully combines the successful prospecting experience of gravity and magnetic exploration in adjacent mining areas.From known to unknown,the plane analysis and profile quantitative inversion of Pandian gravity and magnetic anomalies were carried out,and the whole process interpretation of structural framework division,delineation of metallogenic geological body,anomaly analysis and 2.5D joint inversion is realized in the study area.[Results]Based on comprehensive study of high-pricision gravity and magnetic data,the deep prospecting information under the ultra deep overburden is obtained,and finally achieved a new prospecting breakthrough of skarn type rich iron ore in the central part of Qihe-Yucheng ore concentration area.The three gravity and magnetic anomalies in the ore concentration area are closely related,which proves that the three iron deposits of Dazhang,Pandian and Litun are in the same nearly north-south neutral magmatic rock belt,opening up another important new prospecting space in the Qihe-Yucheng ore concentration area.[Conclusions]The prospecting results provide important refer

关 键 词：超深覆盖区 矽卡岩型铁矿 重磁异常 重磁联合反演 矿产勘查工程 齐河—禹城 山东省 

分 类 号：P618.31[天文地球—矿床学]