陕甘川邻接区基于MAPGIS的金成矿远景区预测  

PREDICTION OF PERSPECTIVE DISTRICTS OF GOLD MINERALIZATION USING MAPGIS IN THE ADJACENT AREA OF SICHUAN,GANSU AND SHAANXI PROVINCES

作　　者：曾佐勋[1] 周继彬[1] 刘立林[1] 胡以铿[1] 樊春[1] 杨巍然[1] 

机构地区：[1]中国地质大学地球科学学院,武汉430074

出　　处：《地学前缘》2001年第2期415-420,共6页Earth Science Frontiers

基　　金：国土资源部"九五"攻关项目! (95 0 2 0 0 2 0 1) ;地质力学开放实验室基金!项目 (dlkf 9812 )

摘　　要：陕甘川邻接区金矿床的展布与滑脱挤出构造、特别是不均匀滑脱关系非常密切。为了定量分析不均匀滑脱与金矿的关系 ,专门研制了自动追踪断裂求取弧形滑脱断裂曲率的计算机软件。经MAPGIS空间分析和多次实验证实 ,区内大中型以上金矿与曲率大于 4的点的密度区关系密切。用Grsip软件 ,对研究区进行断裂密度统计 ,再与金矿床进行MAPGIS空间分析 ,发现断裂密度在 10 0 2 40时 ,对金矿最有利。将研究区的印支—燕山期岩体依出露面积大小划分了大、中、小岩体和岩脉 4种规模的侵入岩。对侵入岩与金矿床MAPGIS空间分析 ,得出了中、小型岩体和岩脉的成矿有利区间分别为岩体边界向外扩展 70 ,6 0和 40个MAPGIS单位的环带。在进行MAPGIS空间分析过程中 ,还分析出研究区的金矿与该区应力异常区也有密切关系 ,但金矿与地层的关系不密切。最后 ,利用MAPGIS空间分析工具对陕甘川邻接区以上金成矿有利因素进行相交分析 ,圈定出 14个一级金矿远景区 ,19个二级金矿远景区和 11个三级金矿远景区。The gold deposits in the adjacent area of Sichuan, Gansu and Shaanxi provinces are closely related to the décollement\|extrusion tectonics, especially to the inhomogeneous décollement. In order to analyze the relationship between the inhomogeneous décollement and the gold deposits, the authors programmed the software to determine the curvatures of the arcuate décollement faults. Through the spatial analysis with MAPGIS and repeated trial, it is considered that the gold deposits in this area are related to the points where the curvatures of the décollement fault are larger than 4. The spatial analysis of MAPGIS indicates that the fracture intensity between 100 and 240 is favorable to gold deposits and that the favorable ranges of magma bodies are the ring ranges with 70, 60 and 40 MAPGIS radial units centred by the boundaries of middle, small magma bodies and veins, respectively, and that the large magma bodies are not favorable to gold deposit. The MAPGIS spatial analysis also indicates that gold deposits are related to the anomalous ranges of the principal stresses, but not closely related to the strata. With the intersection analysis of the favorable factors to the gold mineralization, the authors predicted 14 first\|grade, 19 second\|grade and 11 third\|grade perspective districts of gold mineralization in the study area.

关 键 词：GIS 松潘-甘孜地区 金矿床 成矿远景 成矿预测 滑脱挤出构造 地理信息系统 

分 类 号：P618.51[天文地球—矿床学]