本文關(guān)鍵詞： 礦床地質(zhì) 礦床成因 礦化富集規(guī)律 查涌銅多金屬礦床　出處：《吉林大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：查涌銅多金屬礦床位于青海省玉樹地區(qū),大地構(gòu)造位置屬特提斯—喜馬拉雅構(gòu)造域一部分,位于岡瓦納大陸與歐亞大陸碰撞擠壓地帶,屬于三江多金屬成礦帶。礦區(qū)出露地層主要為三疊系巴塘群第二巖組。礦區(qū)發(fā)育不同時(shí)期的巖漿巖,出露面積均較小,以侵入巖為主,包括晚印支期花崗閃長巖、燕山期石英閃長巖和喜山期輝長巖(33.1±1.8Ma)。其中脈狀銅礦體穿切該輝長巖體,間接限定了成礦時(shí)代,并且?guī)r石地球化學(xué)研究表明巖體具大陸溢流拉斑玄武巖特征,形成于印度板塊與歐亞板塊碰撞后伸展環(huán)境。目前查涌銅多金屬礦區(qū)圈定了4個(gè)主礦體,包括CuI-1、CuI-3、CuI-4、Cu-Pb-Zn-Ag-MoI-5。主要金屬礦物包括黃銅礦、黃鐵礦、方鉛礦、閃鋅礦和少量輝鉬礦等。礦石結(jié)構(gòu)主要包括固溶體分離結(jié)構(gòu)和交代結(jié)構(gòu)等,礦石構(gòu)造以浸染狀構(gòu)造、脈狀構(gòu)造及交錯(cuò)網(wǎng)脈狀構(gòu)造等為主。同時(shí)相應(yīng)圍巖蝕變主要有鉀化、黑云母化、硅化、絹云巖化和碳酸鹽化,呈線性蝕變特征,顯示高溫-低溫的變化特征。利用槽探、鉆探工程進(jìn)行揭露,發(fā)現(xiàn)多條脈狀、透鏡狀礦體,受區(qū)內(nèi)北西西向斷裂構(gòu)造控制明顯。通過對成礦流體研究,表現(xiàn)為包裹體類型簡單,主成礦階段流體顯示中高溫(363.7~415.9℃)、低鹽度(0.53~6.29wt%)、低密度(0.53~0.59g/cm3)的特點(diǎn),通過激光拉曼成分分析,成礦流體中富含H2O、CH4、N2和少量CO2,屬于H2O-NaCl-CH4-N2±CO2體系。計(jì)算求出成礦壓力50~60MPa,對應(yīng)深度5.63~6.22km。硫同位素研究表明成礦流體主要來源于地層還原硫(三疊系地層),并混入部分巖漿硫。鉛同位素顯示主要來源于上地殼,并混入少量下地殼鉛。此次尚未對成礦年齡進(jìn)行測定,但通過測定輝長巖體成巖年齡限定了成礦年齡,屬于喜山期。礦床形成構(gòu)造背景為印度板塊與歐亞板塊碰撞后伸展環(huán)境。通過上面諸多方面研究,進(jìn)而確定其成因類型為中高溫?zé)嵋好}型銅多金屬礦床。通過對查涌銅多金屬礦床礦化富集規(guī)律研究發(fā)現(xiàn),構(gòu)造控礦為該地區(qū)銅多金屬礦床最為顯著特征。具體表現(xiàn)為:走向上礦體相對富集于近東西向斷裂帶內(nèi)及近東西向與北西向斷裂帶交匯處。垂向上礦體相對富集在斷裂產(chǎn)狀變緩部位,從深部向淺部依次為Mo-Cu-Pb、Zn、Ag,呈現(xiàn)一定的元素分帶。橫向上礦脈集中分布呈一系列北東向等距相間平行分布。側(cè)伏規(guī)律上礦脈總體向NWW方向側(cè)伏,從東向西呈現(xiàn)Mo-Cu-Pb、Zn、Ag分帶,其中以西Pb、Zn、Ag品位較高,為進(jìn)一步找礦方向,以東深部巖芯具良好輝鉬礦化信息,指示深部存在隱伏中酸性巖體。
[Abstract]:The Chayong copper polymetallic deposit is located in the Yushu area of Qinghai Province. The geotectonic position is part of the Tethys Himalayan tectonic domain and is located in the collision and compression zone between Gondwana and Eurasia. It belongs to the Sanjiang polymetallic metallogenic belt. The exposed strata of the mining area are mainly the second rock formation of the Triassic Batang group. The magmatic rocks developed in different periods of the mining area are relatively small, with intrusive rocks, including the late Indosinian granodiorite. The Yanshanian quartz diorite and the Himalayan gabbro (33.1 鹵1.8 Ma), in which the vein-like copper ore body pierced the gabbro body, indirectly defined the metallogenic age, and the petrogeochemical study indicated that the rock mass has the characteristics of continental spillway tholeiite basalt. Formed in the extensional environment after the collision of the Indian plate and the Eurasian plate. At present, four main orebodies have been delineated in the Chayong copper polymetallic ore area, including CuI-1C CuI-3U CuI-4U Cu-Pb-Zn-Ag-MoI-5. the main metal minerals include chalcopyrite, pyrite, galena, etc. The ore structure mainly consists of solid solution separation structure and metasomatism structure, ore structure is dominated by disseminated structure, vein structure and staggered vein structure, and the corresponding wall rock alteration is mainly potassium, the ore structure is mainly composed of solid solution separation structure and metasomorphic structure, and the ore structure is dominated by disseminated structure, vein structure and staggered vein structure, etc. Biotite, silicification, sericite and carbonization show linear alteration characteristics, showing the characteristics of high-temperature and low-temperature variations. By means of trough exploration and drilling engineering, many veins and lenticular orebodies have been discovered. It is obviously controlled by the NW-trending fault structure in the area. By studying the ore-forming fluids, the fluid inclusions are characterized by simple inclusions. In the main ore-forming stage, the fluid shows the characteristics of moderate high temperature (363.7U 415.9 鈩，

本文編號：1542394