摘要
山东齐河—禹城地区近年来陆续发现矽卡岩型富铁矿床,铁矿勘查及研究工作取得了较大进展.区内中生代燕山晚期闪长岩体作为成矿地质体,奥陶纪碳酸盐岩作为控矿地层,铁矿床主要赋存于二者的接触部位.由于地处厚覆盖区,新生界平均厚度超过800 m,铁矿找矿难度较大.本文以成矿地质体边界识别及深部特征研究为主要目标,利用最新陆地重力与航空磁力资料,结合前期地质及地球物理勘查成果,分别以化极磁异常、剩余重力异常、磁源重力异常作为初始资料,通过多元化重磁位场转换处理方法,对研究区内成矿地质体进行了三种不同方式的边界识别,并对每种边界识别方法的有效性及准确度进行了讨论和评述.最终优选出磁源重力法作为成矿地质体边界识别的最佳方法,取得了良好的效果,大大缩小了找矿范围.以成矿地质体边界识别为基础,通过重磁长剖面2.5D联合约束反演,构建了本区地质-地球物理找矿模型,进而对成矿地质体垂向深部特征进行了综合研究.模型反映了大张、潘店、李屯重磁异常区内闪长岩体的埋深、厚度及侵位等深部特征,显示出三处成矿地质体可能位于同一近南北向中性岩浆岩带内.本次研究为齐河—禹城地区今后铁矿勘查及研究工作提供了重要指示.
Skarn type rich iron deposits have been found in Qihe-Yucheng area of Shandong Province in recent years, and great progress has been made in iron ore exploration and research.The late Yanshan diorite of Mesozoic era in the area is the metallogenic geological body, and the Ordovician carbonate rock is the ore controlling stratum, the iron deposits mainly occur in the contact part.Because of locating in the thick coverage area, the average thickness of Cenozoic is more than 800 m, iron ore prospecting is difficult.This study takes boundary recognition of the metallogenic geological body and study of its deep characteristics as the primary objective, based on the latest land gravity and aeromagnetic data, combined with the previous geological and geophysical exploration results, taking the RTP(Reduced to the pole) magnetic anomaly, residual gravity anomaly and pseudo-gravity anomaly as the initial data, using multiple gravity and magnetic potential field conversion processing method, three different ways of boundary recognition for the metallogenic geological body in the study area are carried out, the effectiveness and accuracy of each method are discussed and commented.Finally, the pseudo-gravity method is selected as the best way to identify the boundary of the metallogenic geological body, which has achieved good results and greatly reduced the prospecting scope.Based on the boundary identification of the metallogenic geological body, the geological-geophysical prospecting model of the area is established through the 2.5 D joint constrained inversion of gravity and magnetic long section, and then the vertical deep characteristics of the metallogenic geological body are comprehensively studied.The model reflects the buried depth, thickness and emplacement of diorite in Dazhang, Pandian and Litun gravity and magnetic anomaly areas, and shows that the three metallogenic geological bodies may be located in the same nearly north-south neutral magmatic belt. This study provides important indications for the future iron ore exploration and research in QiheYucheng area.
作者
王润生
郝兴中
陈大磊
陈宏杰
刘洪波
王洪军
于露
李瑞
刘辉
刘伟
WANG RunSheng;HAO XingZhong;CHEN DaLei;CHEN HongJie;LIU HongBo;WANG HongJun;YU Lu;LI Rui;LIU Hui;LIU Wei(Shandong Geophysical and Geochemical Exploration Institute,Jinan 250013,China;Shandong Geological Exploration Engineering Technology Research Center,Jinan 250013,China;Shandong Institute of Geological Survey,Jinan 250014,China;China Aero Geophysical Survey and Remote Sensing Center for Natural Resources,Beijing 100083,China)
出处
《地球物理学进展》
CSCD
北大核心
2022年第1期59-68,共10页
Progress in Geophysics
基金
全国重要矿集区找矿预测项目“山东省齐河—禹城矿集区找矿预测(DD2016005223)”
重要锡
锰等矿集区矿产地质调查项目“山东省齐河—禹城矿集区矿产地质调查(DD20190166)”联合资助。
关键词
齐河—禹城
成矿地质体
重磁同源异常
位场转换
边界识别
重磁联合反演
Qihe-Yucheng
Metallogenic geological body
Gravity and magnetic homologous anomaly
Potential field transformation
Boundary recognition
Gravity and magnetic joint inversion
作者简介
王润生,男,1987年生,2010年毕业于中国地质大学(北京),工程师,主要从事深部地球物理勘查技术应用研究工作.E-mail:wrs674@126.com。
