内蒙古中东部浅覆盖区化探岩屑测量方法研究及靶区优选应用  

Geochemical debris survey method in shallow-covered areas in east-central Inner Mongolia and its application in ore target screening

作　　者：张义[1] 聂凤军[1] 孙彬彬[2] 刘占元[2] 江思宏[1] 胡朋[1] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037 [2]中国地质科学院地球物理地球化学勘查研究所,河北廊坊065000

出　　处：《中国地质》2005年第4期696-705,共10页Geology in China

基　　金：国土资源部矿产资源补偿费项目;中国地质调查局地质大调查项目(200310200001-01)资助

摘　　要：内蒙古自治区中东部二连浩特—东乌珠穆沁旗(东乌旗)一带草原区,地貌景观多为平缓山丘类型。因水系沉积物、风积物以及风化残积物等共存,采样介质的不同将直接影响到地球化学测量效果。在东乌旗的阿太乌拉地区和阿巴嘎旗的莫若格钦两地,对比不同粒度的样品,发现金属矿物微颗粒以物理状态不均匀地混合在岩屑介质内。与小于80目的细粒样品相比,小于4目至大于20目之间粒度的岩屑,化探异常的衬值更大,提取的异常也更准确。采用MapInfo软件提供的IDW插值法成图,得到非常清楚的各种元素之间的空间分布关系,直观地显示出找矿有利地段,对找矿靶区的筛选具有良好的指导意义。笔者通过研究,在工作区内发现几处Cu-Au及Ag-Pb-Zn-Cu异常区,并且初步证实存在带状分布的矿化体,找矿前景良好。实践证明,化探岩屑测量为在浅覆盖地区快速锁定矿产普查范围起到了非常重要的作用。The geomorphologic features in the prairie of the Erenhot-Dong Ujimqin Qi area, east-central Inner Mongolia, are mostly represented by gentle hills and mounds. Because of the mixing occurrence of stream sediments, eolian sediments and weathering residues, the results of geochemical surveys are directly affected by different sample media. Comparison of samples of different grain sizes from the Ataiwula property in Dong Ujimqin Qi and Moruogeqin in Abag Qi shows that micro grains of metallic minerals are mixed inhomogeneously in debris carriers. Compared with fine-grained samples （-80 mesh）, the rock debris of-4 to ＋20 mesh has higher geochemical contrast values, and thus their extracted anomalies are also more accurate. A thematic map is constructed using the IDW （Interpolation Distend Weight） method with the Maplnfo program. It shows very clear spatial relationships among various elements and directly indicates favorable sites for mineral finding, which may well guide the screening of ore targets. The authors have found several Cu-Au and Ag-Pb-Zn-Cu anomaly zones in the study area and preliminarily conformed that there are zonal mineralized orebodies and good ore prospects in the area. Through practice, it is demonstrated that geochemical debris sampling and survey play an important role in the rapid localization of the areal extent for mineral reconnaissance in shallow-covered areas.

关 键 词：浅覆盖 化探方法 有效性 内蒙古 

分 类 号：P632[天文地球—地质矿产勘探]