新疆红山糜棱岩型、超糜棱岩型金矿床地质特征及成矿条件分析

红山金矿区大地构造背景属天山地槽北天山地向斜褶皱带,位于康古尔与苦水断裂间狭长的含金韧性剪切带东段北缘,出露地层为中下石炭统.华力西中晚期的多期次岩浆活动、韧性剪切作用和构造活动叠加形成了一系列金及多金属矿床,已成为新疆东部主要的产金基地.通过对红山金矿床地质特征的研究,从宏观及微观尺度进行成矿条件分析,发现金的富集与多金属硫化物,尤其是与方铅矿关系密切.其主要特征是贫黄铁矿,多金属硫化物较少,局部富含方铅矿,金的分布极不均匀.金具多源性,主要来自岩浆,少量来自围岩.剪切作用多次叠加及强烈糜棱岩化,使金矿物与多金属硫化物多沿糜棱面理及显微裂隙分布,最终导致工业矿体侵位,形成糜棱岩型、超糜棱岩型金矿床.

STUDY ON GEOLOGICAL FEATURES AND METALLOGENETIC CONDITIONS OF THE MYLONITE-TYPE AND SUPER-MYLONITE-TYPE GOLD DEPOSIT AT HONGSHAN, XIANJIANG

The geotectonic backgound of the gold field of Hongshan belongs to the area-syncline fold belt of theTianshan geosynclice in the northern Tianshan Mountains. It locates in the north edge of east section of the long, narrow and gold containing ductile shear belt between the Kanguer and Kushui fault. The stratum cropped out is the middle-lower Carboniferous. A series of gold-metal deposits were formed by the magmatic activities, ductile shearing action and the tectonic activity superposition in the middle-later period of Variscan, it has become a main base for gold production in eastern Xinjiang. By studying the geological features of gold deposit in Hongshan, the essay is to analyze the metallogenetic condition from macroscopic and microcosmic corner. It showed that the enrichment of gold is closely related to the polymetallic sulfide, especially the galena. The chief features are the lack of pyrite and polymetallic sulfide and the partly enrichment of galena, with the ununiformity of gold distribution. The gold has a wide source, mainly from magma and a few from country rock. The gold minerals and polymetallic sulfide are distributed along the fissures and mylonitic texture under the frequent shearing action and the strong mylonitize. So the industrial deposits are invaded at last, forming mylonite-type or super-mylonite-type gold deposit.