滇西北中甸红山铜矿矿床地质特征及找矿标志

Geological Characteristics and Prospecting Criteria of Hongshan Copper Deposit in Northwest Yunnan Province

红山铜多金属矿床是滇西北中甸红山—雪鸡坪多金属成矿带上的大型铜多金属矿床,在漫长的地质演化过程中,区域经历了复杂而又频繁的构造—岩浆活动,成矿地质条件优越。详细探讨了区域成矿地质背景、矿床地质特征,厘定了矿床成因及成矿标志。研究表明:①矿区主要出露曲嘎寺组、图姆沟组灰岩、中酸性火山岩,碳酸盐岩过渡层是矿区重要的赋矿层位;②矿区构造发育,角岩、矽卡岩接触带多发育层间裂隙和构造角砾岩破碎带,是有利的赋矿部位;③矽卡岩型铜矿(化)体(V_1～V_4矿体群)多呈层状、似层状产出,产状较稳定、矿化均匀,钼矿体(V_(11))含矿岩性以石英闪长玢岩、二长花岗岩为主,厚度变化较大且品位较低;④矿区于印支期发育矽卡岩型铜矿体,至燕山期被含钼成矿热液进一步富化,形成热液叠加—改造的斑岩-矽卡岩型Cu多金属矿床;⑤矿区地表露头、侵入岩、构造、物化探异常及矿化为有利的找矿标志。

Hongshan Copper-polymetallic Deposit is a large polymetallic deposit in Zhongdian Hongshan-Xuejiping polymetallic metallogenic belt in Northwest Yunnan Province.The mining area is experienced a long and complex tectonic-magmatic activity,which is characterized by the superior metallogenic geological conditions.The geological characteristics of the mining area and deposit are discussed,the deposit genesis and prospecting criteria are analyzed.The research results show that:①the mining area is mainly occurred limestone and intermediate-acid volcanic rock in Qugasi Formation and Tumugou Formation,and the orebodies are mainly hosted in the transition-layer of carbonate;②structure of the mining area is well developed,the interlayer fractured-zone and tectonic breccia fractured-zone in the contract zone between hornstone and skarn are the favorable ore-bearing position;③the skarn-type copper orebodies (mineralization) are occurred with layered and stratiform-like,which are characterized by steady occurrence and uniform mineralization,the molybdenum orebodies are occurred in quartz diorite porphyrite and adamellite,which are characterized by varied thickness and low grade;④the skarn-type copper orebodies have developed in Indo-Chinese Epoch,and enriched by hydrothermal ore-forming with molybdenun in Yanshanian,the genesis of Hongshan porphyry-skarn type deposit can be attributed to hydrothermal superimposed reformation;⑤the surface occurrence,intrusive rock,structures,geophysical-geochemical anomaly and mineralization can be taken as the favorable prospecting Criteria in Hongshan mining area.