文档介绍：安徽铜陵冬瓜山铜金矿床和胡村铜钼矿床蚀变特征及成矿作用摘要冬瓜山铜金矿床和胡村铜钼矿床是安徽铜陵狮子山铜等多金属矿田中的重要矿床。本文在全面认识铜陵狮子山矿田的区域地质背景和矿床地质特征基础上,系统研究了冬瓜山矿床和胡村矿床深部岩浆岩体的地质特征及其蚀变与矿化,确定了岩体和围岩中的蚀变类型、蚀变分带及蚀变矿物组合特征,再结合前人研究成果,探讨了冬瓜山矿床和胡村矿床的成矿作用及成因。研究认为,冬瓜山铜金矿床和胡村铜钼矿床都具有上下两部分矿体,上部为矽卡岩型矿体,下部为斑岩型矿体;冬瓜山深部矿床蚀变分带具有一定的规律,自岩体中心向围岩依次为钾长石化蚀变带(钾长石化、硅化)一石英一绢云母蚀变带(绢云母化、硅化)一矽卡岩化带一角岩一大理岩化带,而胡村深部虽然发育斑岩型矿床类型蚀变,但分带不明显;与世界各主要构造带斑岩型矿床相比,冬瓜山矿床主要发育钾长石化,而世界斑岩型矿床以黑云母化为主; 冬瓜山矿床外围青磐岩化蚀变带不发育,虽然发育有泥质蚀变,但不足以成带; 冬瓜山矿床下部矿体蚀变可分为三种:钾硅酸盐化蚀变、石英一绢云母化蚀变和矽卡岩化蚀变;钾硅酸盐化蚀变产于靠近岩体中心部位,主要表现为强烈的钾长石化和硅化:石英一绢云母化蚀变叠加在钾硅酸盐化蚀变之上,发育在岩体及其接触带上,矿物组合以石英、绢云母、黄铁矿为主;矽卡岩化蚀变主要发育在沉积地层中以及岩体与围岩接触带上,矽卡岩化的矿物组合以石榴子石、透辉石、方解石或以橄榄石、蛇纹石、透辉石、斜硅镁石、绿泥石为主。与典型斑岩型矿床对比,虽然冬瓜山矿床和胡村矿床下部矿体的蚀变分带相对不完整或不甚明显,但矿化都与侵入岩体有关,且两个矿床的下部矿体均呈浸染状、细脉浸染状或网脉状产出,矿床流体包裹体、微量元素和同位素地球化学研究结果也表明,成矿作用与燕山期岩浆作用密切相关。因此,冬瓜山铜金矿床和胡村铜钼矿床都应属于矽卡岩一斑岩型矿床。关键词:蚀变特征;成矿作用;冬瓜山铜金矿床;胡村铜钼矿床;安徽铜陵 The Alteration characteristics andMineralization in Dongguashan Copper—gold deposit and Hucun Copper—molybdenum deposit ofTongling, Anhui pr0Vince ABSTRACT Dongguashan Copper—gold deposit and Hucun Copper-molybdenum deposit are important deposits in Shizishan copper-polymetallic ore—field of Tbngling region, Anhui Province. Based on the general understanding of the regional geological background andgeological featuresofTbngling Shizishan ore field,the geological f-eatures,alteration and mineralization of Dongguashan Copper—gold deposit and Hucun Copper—molybdenum deposit were alteration type,alteration zoning and mineral assemblages ofintrusions and wall—rock were confirmed. Combing with preVious achieVements of other scholars, the mineralization andgenesis ofDongguashan and Hucun deposits were discussed. According topriVous materials,the ore bodies ofDongguashan Copper—gold deposit and Hucun copper-molybdenum deposit both haVe two upper part is skarn type,and the deeper part isporphyry alteration zone of Dongguashan deep deposit is regularly potassic alteration (K—f色ldspation, silicincation)_phyllicalteration(sericitiza