本文選題：天寶山鉛鋅礦床 + 成礦階段��； 參考：《中國地質(zhì)大學(xué)(北京)》2017年碩士論文

【摘要】：天寶山鉛鋅礦床位于揚(yáng)子板塊西南緣,是川滇黔鉛鋅礦集區(qū)的重要組成部分之一。本文通過野外觀察、室內(nèi)鑒定、地球化學(xué)等方法,系統(tǒng)研究天寶山鉛鋅礦床的成因,并對區(qū)域鉛鋅成礦動力學(xué)背景進(jìn)行初步的探討。天寶山鉛鋅礦床產(chǎn)在震旦系燈影組白云巖地層中,具有后生成礦特征,礦體受構(gòu)造斷裂控制明顯,礦區(qū)內(nèi)巖漿巖不發(fā)育,未見中酸性侵入巖,僅發(fā)育輝綠巖脈。根據(jù)礦石、礦物組合特征及其組構(gòu)和穿插關(guān)系,將成礦期次劃分為黃銅礦-閃鋅礦-黝銅礦-毒砂階段和閃鋅礦-方鉛礦-黃鐵礦-方解石階段,其中黃銅礦-閃鋅礦-黝銅礦-毒砂階段的成礦溫度為300~370℃,為中-高溫?zé)嵋撼傻V,閃鋅礦-方鉛礦-黃鐵礦-方解石階段成礦溫度為150~250℃,為中-低溫?zé)嵋撼傻V。硫化物δ34S值指示成礦流體中的硫來源于巖漿熱液,成礦晚期脈石方解石的C-O同位素指示該階段成礦熱液中的碳和氧來源于溶解了海相碳酸鹽巖的沉積建造水和巖漿熱液混合。不同成礦階段的閃鋅礦微量元素特征指示黃銅礦-閃鋅礦-黝銅礦-毒砂階段具有巖漿熱液成礦特征,閃鋅礦-方鉛礦-黃鐵礦-方解石階段具有低溫?zé)嵋撼傻V特征。因此認(rèn)為,天寶山鉛鋅礦床屬于中溫?zé)嵋好}型鉛鋅礦床,前期主要是巖漿熱液參與成礦,后期有地層建造水和大氣降水加入。前人研究川滇黔礦集區(qū)鉛鋅礦床的成礦年齡在190~230Ma之間,本文對區(qū)域上三疊系碎屑巖進(jìn)行綜合研究,厘定了區(qū)域鉛鋅成礦的動力學(xué)背景。研究結(jié)果顯示,川滇黔礦集區(qū)三疊系盆地沉積環(huán)境與鉛鋅成礦構(gòu)造動力學(xué)背景相一致,形成于印支期造山運(yùn)動背景下。印支造山運(yùn)動引起板塊碰撞拼合,產(chǎn)生強(qiáng)烈擠壓作用,導(dǎo)致越北古陸和江南古陸抬升被剝蝕,碎屑物源向內(nèi)陸搬運(yùn)并沉積成巖,同時(shí)盆地流體向內(nèi)陸運(yùn)移,深部流體沿構(gòu)造斷裂上升,在川滇黔接壤區(qū)沉淀成礦。
[Abstract]:Tianbaoshan lead-zinc deposit is located in the southwest margin of Yangtze plate and is one of the important components of Sichuan Yunnan Guizhou lead-zinc deposit concentration area. By means of field observation, laboratory identification and geochemistry, this paper systematically studies the genesis of Tianbaoshan lead-zinc deposit, and preliminarily discusses the dynamic background of regional lead-zinc mineralization. The Tianbaoshan lead-zinc deposit occurs in dolomite strata of Dengying formation of Sinian system and has the characteristics of post-forming ore deposits. The orebody is obviously controlled by structural faults, magmatic rocks are not developed in the mining area, no intermediate-acid intrusive rocks are found, but only diabase veins are developed. According to the characteristics of ore and mineral assemblages and their fabric and intercalation relationships, the metallogenic stages are divided into chalcopyrite, sphalerite, tetrahedrite and arsenopyrite, and sphalerite galena, pyrite and calcite. The metallogenic temperature of chalcopyrite-sphalerite-pyrite-arsenopyrite stage is 300 ~ 370 鈩，

本文編號：2002555