综合地球物理方法找矿应用:以智利科皮亚波地区月亮山磁铁矿型IOCG矿床为例  

Application of integrated geophysical method in prospecting:A case study of the magnetite-type IOCG deposits in the Moon Mountain exploration area,Copiapo,Chile

作　　者：李天成[1,2] 方维萱 王磊[1] 陈家乐[1] 张平[1] LI Tiancheng;FANG Weixuan;WANG Lei;CHEN Jiale;ZHANG Ping(China Non-Ferrous Metals Resource Geological Survery,Beijing 100012,China;Beijing Institute of Geology for Mineral Resources,Beijing 100012,China)

机构地区：[1]有色金属矿产地质调查中心,北京100012 [2]北京矿产地质研究院,北京100012

出　　处：《地质力学学报》2022年第1期22-35,共14页Journal of Geomechanics

基　　金：国土资源部公益性行业科研专项基金(201511016-1);国家科技支撑计划(2006BAB01B09);科技部科研院所技术开发专项(2011EG115022)。

摘　　要：智利科皮亚波地区地处海岸山带东侧的智利铁带北段,已发现多个中—大型磁铁矿型IOCG矿床,该类矿床的形成与大洋俯冲背景下陆缘弧中性—铁镁质火山岩和火山-沉积建造中早白垩世中酸性岩浆岩的侵入中心密切相关。该成矿带大面积被第四系砂砾层覆盖,在成矿地质特征研究基础上,采用综合地球物理方法对覆盖层下隐伏矿床(体)进行定位预测成为技术关键并具有现实需求。通过深入研究科皮亚波地区磁铁矿型IOCG矿床的成矿地质特征,并采用航磁深部地质解译初选勘查靶区,结合磁铁矿型IOCG矿床成矿地质-物性参数统计分析,建立了勘查区磁铁矿型IOCG矿床成矿地质-地球物理异常模式,采用综合地球物理方法在月亮山勘查区第四系覆盖区圈定的深部靶位经钻孔验证,发现了大型隐伏磁铁矿型IOCG矿床。Many medium to large magnetite-type IOCG deposits have been found in the Copiapo area of Chile,which is located in the north fragment of the Chilean iron belt on the east side of the coastal mountain belt.The formation of these deposits is closely related to the neutral mafic volcanic rocks in the continental margin arc under the background of ocean subduction and the intrusion center of Early Cretaceous intermediate-acid magmatic rocks intruded in the volcanic sedimentary formation.The metallogenic belt is largely covered by Quaternary gravel layer.Using integrated geophysical methods with metallogenic geological characteristics to locate the concealed deposits(ore-bodies)under the overburden has become a key technology and a practical demand.We conducted an in-depth study of the metallogenic geological characteristics of magnetite-type IOCG deposits in the Copiabo area,and interpreted the preliminary exploration target by aeromagnetic deep-geological interpretation.Combining the interpretation results with the statistical analysis of metallogenic geological-physical parameters of magnetite-type IOCG deposits,a metallogenic geological-geophysical anomaly model of magnetite-type IOCG deposits in the Copiabo area is established.A large concealed magnetite-type IOCG deposit was found and verified by drilling in the deep target area delineated in the Quaternary coverage area of the Moon Mountain exploration area by using the integrated geophysical method.

关 键 词：智利海岸山带 阿塔卡玛断裂带 岩浆弧 地质-地球物理建模 IOCG矿床 综合地球物理 

分 类 号：P612[天文地球—矿床学] P631[天文地球—地质学]