新疆北山西段裂谷演化及金矿成矿规律

新疆北山裂谷构造带,呈北东东—北西西向展布,是在塔里木地块太古界、元古界的基础上开裂演化而成,总体呈两地块夹裂谷的构造格局,经历了∈、O-S、C-P三次大规模的裂开与闭合、由南向北迁移的演化模式。在该裂谷带晚古生代沉积盖层中分布着一系列不同类型的金矿(点),并划分了多个Au成矿亚带。本文所论为新疆北山晚古生代金(铜)Ⅴ级成矿带金矿的成矿规律。根据赋矿岩系划分为6类,矿石建造划分为四类,分别为石英脉型、破碎蚀变岩型、破碎蚀变岩型 石英脉型、中酸性岩浆热液型,以石英脉 破碎蚀变岩型为主。控矿因素为沉积建造(火山岩—碎屑岩及炭质岩系)、韧—脆性断裂、岩浆岩等;成矿时代为华力西晚期、印支期、燕山期和喜山期,成矿作用与各期构造活动同步或准同步。

RIFT EVOLUTION AND GOLD METALLOGENICS IN THE WEST SECTION OF THE NORTH MOUNTAIN,SINKIANG

The rift structural zone in the north mountain of Sinkiang,striking in NEE and NWW directions,was formed by dehiscence on the basis of the Archean and Proterozoic Tarim massifs.In general,it presents a structural pattern of a rift intercalated in two massifs,which passed three phases of dehiscence and convergence during Cambrian,Ordovician-Silurian and Carboniferous-Permian periods and,evolution model of transference from south to north.A series of different types of gold deposits(occurrences) are distributed in the late Paleozoic sedimentary covers in the rift zone,which are divided into many gold mineralized sub-zones.The gold mineralization in the later Paleozoic gold(copper) V-grade metallogenic zone in the north mountain,Sinkiang is discussed in this paper.Six types of ore-bearing rock series and four types of ore formation have been distinguished.They are: quartzvein type,fractured-altered rocks,fractured-altered rocks quartz-vein type,intermediate-acid magmatic hydrothermal type and quartz-vein fractured-altered rock type.The major ore-controlled factors are sedimentary formation(volcanic rock-detrital rock-carbonaceous rock series),ductile-brittle fault and magmatic rocks.The metallogenic age is the late Variscan period,Indosinian period,Yanshanian and Himalayan periods.Mineralization occurred in the same or almost same time with tectonic activities in each period.