铜陵市林家冲老硐地质特征及其找矿意义  

Geological characteristics and prospecting significance of Linjiachong old mining adit in Tongling city

作　　者：赵坦 张纪田 梁树旺 ZHAO Tan;ZHANG Jitian;LIANG Shuwang(The East China Metallurgical Geological Exploration Insstitute,Hefei 230068,China)

机构地区：[1]华东冶金地质勘查研究院,合肥230088

出　　处：《地质找矿论丛》2023年第3期319-325,共7页Contributions to Geology and Mineral Resources Research

摘　　要：铜陵市林家冲老硐中的金矿化脉产于石英闪长斑岩中,位于辉石闪长岩的外接触带;围岩蚀变和金的矿化严格受曹家冲断裂带的次级断裂控制,与金矿化相关的热液蚀变有黄铁绢英岩化、硅化和黄铁矿化;金矿化类型为石英-黄铁矿脉型。林家冲老硐附近的迪龙冲金矿亦产于石英斑岩中,但在控矿构造特征和金矿化类型方面二者具有一定差异。研究认为,不同的控矿构造中均可以出现蚀变和多矿化,但矿化类型和矿化规模可有区别;舒家店地区的3个岩体(石英闪长斑岩、辉石闪长岩和石英二长闪长岩)均为铜、金矿的成矿岩体和赋矿岩石;舒家店地区的铜矿化和金矿化是同期不同矿化阶段的关系,斑岩型铜(金)矿床位于热液活动的中心部位(与辉石闪长岩范围相当),而脉状金矿床(点)则产于热液活动中心周边的岩体或地层中,受断裂(裂隙)的控制,这一特点与斑岩矿床的分带规律是一致的。Au mineralization veins in the Linjiachong old mining adit occur in quartz dioxide at the outer contact zone of pyroxene diorite Wall rock alteration and Au mineralization are strictly controlled by sub-faults of Caojiachong fractured zone.Hydrothermal alteration related to Au mineralization includes pyrite phyllic alteration,silicification,pyritization.Au mineralization belongs to quartz-pyrite vein type.The near-by Dilongchong Au deposit occurs in quartz porphyry.Characteristics of ore-control structure and Au mineralization type of the Linjiachong old mining adit differs from those of Dilongchong Au deposit.Study on the Au mineralization shows that alterations and muti-mineralization types occur in different ore-control structures and the difference is the scale and type of mineralization.There are three intrusive bodies(quartz dioritic porphyry,pyroxene diorite and quartz monzonitic diorite)in Shujiadian area.They are all the host rock of Au,Cu ore deposit.Au mineralization and Cu mineralization are the products of different mineralization stage.Porphyritic Cu(Au)deposit(mineralization)occurs at center of hydrothermal activity corresponding to scope of pyroxene diorite,vein type Au deposit(occurrence)at periphery of the center or in strata around the intrusive body and controlled by fault or fracture.Such characteristics is coincided with zoning of porphyritic deposit.

关 键 词：林家冲老硐 金矿脉 石英-黄铁矿脉型金矿 成矿机制 铜陵市 安徽省 

分 类 号：P613[天文地球—矿床学] P618.51[天文地球—地质学]