【摘要】：哀牢山構(gòu)造帶是我國重要的貴金屬和有色金屬成礦區(qū)帶。長安銅鉬金礦集區(qū)位于哀牢山金屬成礦帶西南部的金平推覆體中南部,由長安金礦、銅廠銅鉬礦和長安沖銅鉬礦等多金屬礦床組成。礦集區(qū)內(nèi)巖漿活動主要發(fā)生在喜山期,巖石類型為從基性到中酸性的巖石系列,包括輝長巖、輝綠巖、正長巖、正長斑巖、花崗斑巖和少量花崗閃長巖組合,多呈巖基或小巖株產(chǎn)出,多類型多期次巖體侵入最終構(gòu)成復(fù)式巖體,屬于準(zhǔn)鋁質(zhì)-弱過鋁質(zhì)的堿性富鉀巖類。巖石地球化學(xué)特征與哀牢山-金沙江構(gòu)造帶南段堿性帶內(nèi)的堿性巖漿巖特征一致,巖漿為來源于含金云母的尖晶石相地幔的部分熔融形成富鉀質(zhì)堿性巖漿。鋯石LA-ICP-MS U-Pb定年結(jié)果表明礦集區(qū)內(nèi)巖漿活動發(fā)生于37~21Ma。其中,形成于35~21Ma的花崗斑巖和正長斑巖對斑巖型銅鉬礦和破碎蝕變巖型金礦的形成有直接或間接控制作用。礦集區(qū)內(nèi)主要發(fā)育兩組走向北西、傾向北東的逆沖斷裂和走向北東傾向北西的層間走滑斷裂構(gòu)造。它們在空間上控制了巖體和礦體的空間分布,是導(dǎo)礦和儲礦構(gòu)造。長安礦集區(qū)內(nèi)的斑巖銅鉬礦體呈板狀、疊瓦狀、透鏡狀、條帶狀、斑雜狀及塊狀產(chǎn)于斑巖和碳酸鹽接觸地帶。圍巖蝕變具有明顯的分帶性,即從巖體向碳酸鹽巖依次為云英巖化、矽卡巖化和碳酸巖化。其中,鉬礦主要分布在云英巖化帶,銅礦主要分布在矽卡巖化帶。金礦分布于巖體外部構(gòu)造破碎帶中,圍巖主要為粉砂巖類,硅化、黃鐵礦化和碳酸巖化蝕變明顯,礦化主要與硅化和黃鐵礦化有關(guān)。穩(wěn)定同位素結(jié)果表明斑巖銅鉬礦成礦物質(zhì)和成礦流體主要來源于巖漿,金礦成礦物質(zhì)來源于巖漿,成礦流體為巖漿流體和地下水的混合物。成礦作用形成于35~21Ma。構(gòu)造地質(zhì)學(xué)、巖石學(xué)、同位素地質(zhì)學(xué)分析結(jié)果表明新生代巖漿沿礦集區(qū)內(nèi)北西向和北東向兩組斷裂交匯地帶侵入,巖漿期后熱液與圍巖發(fā)生交代作用,形成云英巖化、矽卡巖化和碳酸巖化蝕變,Cu、Mo等成礦物質(zhì)以硫化物的形式析出,形成銅鉬礦。同時,中低溫流體沿構(gòu)造帶向外運移,在遠離巖體的構(gòu)造破碎帶中與地下流體會合,致使成礦流體的物理化學(xué)條件發(fā)生巨大變化,促使攜帶金元素的絡(luò)合物分解,在發(fā)生硅化、黃鐵礦化和碳酸巖化蝕變的同時金隨石英、黃鐵礦或方解石一起沉淀,形成金礦床。
[Abstract]:Ailaoshan tectonic belt is an important metallogenic zone of precious metals and nonferrous metals in China. Changan copper-molybdenum gold deposit is located in the south and central of Jinping nappe in the southwest of Ailaoshan metallogenic belt. It is composed of Changan gold deposit, Tongchang copper-molybdenum deposit and Changan chong copper-molybdenum deposit and other polymetallic deposits. Magmatic activity in the ore concentration area mainly occurred in the Himalayan period, and the rock types are from basic to intermediate acid rock series, including gabbro, diabase, syenite, granitic porphyry and a small amount of granodiorite assemblage. Most of them occur in rock base or small rock, and many types of intrusions constitute complex rock bodies, which belong to the type of alkaline potash rich rocks with quasi-aluminite and weak peraluminite. The petrogeochemical characteristics are consistent with the alkaline magmatic rocks in the alkaline zone of the southern Ailaoshan-Jinshajiang structural belt. The magma is derived from the partial melting of the spinel mantle containing phlogopicite to form potash alkaline magma. The results of zircon LA-ICP-MS U-Pb dating indicate that magmatic activity occurred in the ore concentration area at 37 ~ 21 Ma. Among them, granitic porphyry and syenite porphyry formed in 35~21Ma have direct or indirect control on the formation of porphyry copper-molybdenum deposit and broken altered rock type gold deposit. There are two groups of thrust faults trending to the north and east and interlayer strike-slip faults trending to the north to the west in the ore concentration area. They control the spatial distribution of rock mass and orebody in space and are ore-conducting and ore-storage structures. The porphyry copper-molybdenum bodies in Changan ore concentration area are plate-like, imbricate, lenticular, banded, variegated and massive in porphyry and carbonate contact zone. The alteration of the surrounding rock has obvious zonation, that is, from the rock mass to the carbonate rock, it is followed by quartzization, skarnization and carbonatilization. The molybdenum ore is mainly distributed in the dolomization zone, and the copper deposit is mainly distributed in the skarn zone. The gold deposit is distributed in the structural fracture zone outside the rock mass, and the surrounding rock is mainly siltstone, silicification, pyrite and carbonatizing alteration. The mineralization is mainly related to silicification and pyrite mineralization. The results of stable isotopes show that the ore-forming material and ore-forming fluid of porphyry copper-molybdenum ore are mainly derived from magma, the ore-forming material of gold ore comes from magma, and the ore-forming fluid is a mixture of magmatic fluid and groundwater. The mineralization was formed at 35 ~ 21 Ma. The results of tectonic geology, petrology and isotopic geology analysis indicate that the Cenozoic magma intruded along the intersection zone of faults in the NW and NNE directions in the ore concentration area, resulting in the metasomatism of the hydrothermal solution and the surrounding rock in the post-magmatic period, resulting in the formation of dolomite. Skarn and carbonatized alteration, Cu,Mo and other ore-forming materials precipitate in the form of sulphide to form copper-molybdenum ore. At the same time, the intermediate-low temperature fluid moves outward along the tectonic belt and converges with the underground fluid in the tectonic fracture zone far from the rock mass, which results in great changes in the physical and chemical conditions of the ore-forming fluid, which promotes the decomposition of the complex carrying gold elements and silicification. At the same time, gold deposits are precipitated with quartz, pyrite or calcite during the alteration of pyrite and carbonatite to form gold deposits.
【學(xué)位授予單位】：中國地質(zhì)大學(xué)(北京)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：P618.41;P618.65;P618.51

【參考文獻】

相關(guān)期刊論文 前10條

1 方維萱,胡瑞忠,謝桂青,蘇文超;云南哀牢山地區(qū)構(gòu)造巖石地層單元及其構(gòu)造演化[J];大地構(gòu)造與成礦學(xué);2002年01期

2 黃波;梁華英;莫濟海;謝應(yīng)雯;;金平銅廠銅鉬礦床賦礦巖體鋯石LA-ICP-MS U-Pb年齡及意義[J];大地構(gòu)造與成礦學(xué);2009年04期

3 侯增謙,鐘大賚,鄧萬明;青藏高原東緣斑巖銅鉬金成礦帶的構(gòu)造模式[J];中國地質(zhì);2004年01期

4 鄧軍,楊立強,翟裕生,孫忠實,陳學(xué)明;構(gòu)造-流體-成礦系統(tǒng)及其動力學(xué)的理論格架與方法體系[J];地球科學(xué);2000年01期

5 吳海威,張連生,嵇少丞;紅河-哀牢山斷裂帶——喜山期陸內(nèi)大型左行走滑剪切帶[J];地質(zhì)科學(xué);1989年01期

6 林清茶;夏斌;張玉泉;;中國西部喀喇昆侖—昆侖山地區(qū)火山巖的~(40)Ar-~(39)Ar年齡及地質(zhì)意義[J];地質(zhì)科學(xué);2007年02期

7 TRAN My Dung;;Regional Metallogenesis of the Chang'an Gold Ore Deposit in Western Yunnan:Evidences from Fluid Inclusions and Stable Isotopes[J];Acta Geologica Sinica(English Edition);2010年06期

8 張玉泉,夏斌,梁華英,劉紅英,林清茶;云南大平糜棱巖化堿性花崗巖的鋯石特征及其地質(zhì)意義[J];高校地質(zhì)學(xué)報;2004年03期

9 和中華;王勇;莫宣學(xué);曾普勝;喻學(xué)惠;劉和林;;云南金平長安金礦成礦物質(zhì)來源——來自礦石及地層、巖漿巖的成礦元素含量證據(jù)[J];東華理工大學(xué)學(xué)報(自然科學(xué)版);2008年03期

10 孫崇波;王道永;;哀牢山造山帶九甲—安定金礦帶礦化地質(zhì)特征及控礦因素分析[J];礦物學(xué)報;2011年S1期

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