甘肃祁连山西段金矿分布特征及控矿因素分析

GEOLOGICAL CHARACTERISTICS AND ORE-CONTROLLING FACTORS OF GOLD DEPOSITS IN WESTERN QILIAN,GANSU PROVINCE

祁连西段是甘肃省重要的金成矿带,分布有鹰嘴山、寒山、阳凹大泉、车路沟、金湾子等金矿床,近年又新发现豹子沟南、滴水山、牛毛泉、积阴功台金矿,显示出较大的区域找矿潜力。本文通过典型金矿床和新发现金矿成矿地质条件分析,总结了甘肃祁连山西段金矿的空间分布特征、控矿因素。初步研究认为祁连山西段主要的金矿床呈带状分布于阿尔金走滑断裂与北祁连褶皱断裂构造带交汇部位,明显受不同规模、不同序次的韧、脆性断裂构造破碎带控制;成矿与区域内不同规模中酸性—中基性岩体及岩脉有关;古生代火山碎屑岩、浅变质碎屑岩为主要容矿岩性及含矿建造;矿体普遍具有延深大于延长、深部明显富集的特征。新发现金矿多以化探异常查证为重点,不断浓缩异常源,实现找矿突破。本文对祁连山西段的金矿勘查具有指导意义,对该地区的金矿研究也提供了重要的基础资料。

The studying area is located in the Subei-Xiangmaoshan Au-Cu-Pb-Zn metallogenic subzone of North Qilian Cu-Pb-Zn-Au-W-Mo metallogenic belt. The dominant mineral species are Au, Cu, W, Mo, Pb-Zn,Ag and Fe. As one of the most important and potential area of gold-mineralizing, the typical gold deposits are Yingzuishan, Hanshan, Yangaodaquan, Chelugou, Jinwanzi, South Baozigou gold deposits, all of which have similar metallogenic settings and show the large gold prospecting potential in West Qilian. The spatial-distributing characteristics and ore-control factors of gold deposits are concluded, and the direction and methods of gold exploration are pointed out in the article. According to the comparison of geological characteristics and ore-controlling factors, it is concluded that the gold deposits are occurred in the NE, NW faults, and influenced by the magma intrusive activity. The ore-bearing rocks are mainly the pyroclastic and shallow metamorphic clastic in Paleozoic. The typical characteristics of gold ore bodies in Western Qilian are that the depth the vein lies underground is greater than the length of the vein, the gold grade is more higher in the depth. The author also suggested that the working methods of further exploration is middle-large scale geochemical survey in order to achieve prospecting breakthrough with the check and testify of geochemical abnormities. It is significant to the gold prospecting and studying in West Qilian.