本文關(guān)鍵詞： 東天山 覺羅塔格 阿齊山鉛鋅礦 地球化學(xué) 礦床成因　出處：《中國地質(zhì)大學(xué)(北京)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：新疆東天山阿齊山鉛鋅礦位于新疆東天山覺羅塔地區(qū)阿齊山-雅滿蘇島弧帶地區(qū)。本文對(duì)阿齊山鉛鋅礦進(jìn)行深入的野外地質(zhì)調(diào)查,運(yùn)用巖石地球化學(xué)、電子探針、流體包裹體測溫及穩(wěn)定同位素、Sm-Nd等時(shí)線測年,對(duì)礦床的成礦地質(zhì)特征、大地構(gòu)造背景、物質(zhì)來源、礦化時(shí)代等進(jìn)行了研究,對(duì)阿齊山鉛鋅礦床成因取得如下認(rèn)識(shí):阿齊山鉛鋅礦賦存下石炭統(tǒng)雅滿蘇組安山質(zhì)凝灰?guī)r中。礦石類型主要為浸染狀、條帶狀、塊狀礦石為主。成礦經(jīng)歷了4個(gè)階段:以石榴子石-透輝石為主的熱液成礦早期階段,礦物包裹體測溫揭示,均一溫度為288℃;綠簾石-透閃石-磁鐵礦為主的熱液成礦晚期階段,均一溫度達(dá)到最高,為340℃;硫化物階段以石英-綠簾石-綠泥石為主的均一溫度降低至224℃;方解石等碳酸鹽階段,溫度最低,到達(dá)130℃。阿齊山鉛鋅礦區(qū)火山巖屬中-基性系列,屬鈣堿性系列,原始地幔微量元素標(biāo)準(zhǔn)化圖中巖石表現(xiàn)富集輕稀土元素(LREE)和大離子親石元素(LILE,如Rb、Th、K),虧損重稀土元素(HREE)和高場強(qiáng)元素(HSFE;如Nb、P、Ti),為典型的島弧火山巖特征;在球粒隕石標(biāo)準(zhǔn)化REE分布型式中,輕稀土分餾明顯,但是重稀土分布平緩,顯示輕稀土相對(duì)重稀土富集的現(xiàn)象。阿齊山鉛鋅礦石榴子石屬于鈣鐵榴石-鈣鋁榴石系列,由中心向邊緣進(jìn)行剖面分析,其主量元素具有一定規(guī)律變化,SiO_2和CaO基本無變化,TFeO呈遞增趨勢,Al_2O_3含量減少,反映在石榴子石形成早期,可能為酸性環(huán)境;形成過程中成礦溶液由酸性向弱堿性演化。石榴子石早期矽卡巖階段為Pb、Zn等金屬硫化物富集提供了有利空間。測得硫化物的δ~(34)S主要集中在-5‰左右,具有典型火山熱液硫同位素特征。與鉛鋅礦、黃銅礦共生的蝕變礦物(石榴子石、綠簾石)Sm-Nd等時(shí)線年齡為292Ma,代表著阿齊山鉛鋅礦形成于晚石炭世火山-巖漿作用晚期,與晚石炭世淺成斑巖體侵入有關(guān)。結(jié)合以上研究初步判定為火山熱液型鉛鋅礦床。
[Abstract]:The AQishan Pb-Zn deposit in East Tianshan, Xinjiang, is located in the AQishan Yarmansu Island Arc Zone in Jolata area, East Tianshan, Xinjiang. In this paper, an in-depth field geological survey of the AQishan Pb-Zn deposit was carried out, and geochemistry and electron probe were used to investigate the Pb-Zn deposit. Fluid inclusion temperature measurement and stable isotopic Sm-Nd isochron dating have been carried out to study the metallogenic geological characteristics, tectonic background, material source and mineralization age of the deposit. The genesis of the AQishan Pb-Zn deposit has been recognized as follows: the AQishan Pb-Zn deposit exists in Anshan tuff of the Lower Carboniferous Yamansu formation. The ore types are mainly disseminated and banded. The ore-forming process has experienced four stages: the early stage of hydrothermal mineralization, which is mainly garnet and diopside, the homogenization temperature of mineral inclusions is 288 鈩，

本文編號(hào)：1497778