内蒙古苏尼特左旗地区韧性剪切带及其控矿作用研究——以巴彦温都尔金矿为例
The Ductile Shear Zones and their Ore-Control Process in Sunitezuoqi Area, Inner Mongolia: A Case Study on Bayanwenduer Gold Deposit
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摘要: 对区域地质分析表明,在晚古生代,由于南北两大板块对接碰撞及其后持续挤压作用,致使区内韧性剪切带发育,由北至南形成3条大型韧性剪切带.它们对区内金矿床(点)的分布具有明显的控制作用.剪切带经历了自华力西晚期至燕山早期3个韧性变形时期,每个时期均伴随不同阶段金元素的活化、迁移以及富集成矿.深壳剪切活动为金成矿提供了热动力和容矿空间;同时剪切带活动过程中,伴随了区内多期次岩浆活动,也为金成矿提供热动力和成矿物质.通过对巴彦温都尔金矿剪切带内金矿脉特征分析表明:剪切带内裂隙是金元素富集成矿的有利部位;总结了苏尼特左旗地区与韧性剪切带有关的金矿床的成矿演化模式,并初步指出在区内金矿勘查中应注意的找矿方向.Abstract: Based on the regional geological analysis,we know that there are 3 large-scale ductile shear zones from north to south in the studied area,which were caused by the collision and continual extrusion between South Plate and North Plate during the late Paleozoic Era.The ductile shear zones controlled the distribution of the gold deposits in the area.Three ductile deformation periods could be marked out from the late Variscanic period to the early Yanshanian period,and accompanied by gold activation,transfer and enrichment for different stages.The shear of deeper earth's crust andmagmatic activities provided the heat power andm inerallogenic elements and hold space for gold mineralization.The characteristics of gold vein (in Bayanwenduer shear cane) show that the fissures in shear canes are the favoredplace for enrichmentof Au element.Them etallogenic model of gold deposit related with ductile shear canes in Sunitezuoqi area,and ore-founding direction for gold are put forward.