【作者】 霍亮；

【导师】 孙丰月；

【作者基本信息】 吉林大学 ， 矿物学、岩石学、矿床学， 2010， 博士

【摘要】 西昆仑地区位于青藏高原北部,塔里木盆地南缘,矿产资源丰富,是我国重要的多金属成矿带之一。根据西昆仑造山带库地—其曼于特蛇绿岩带、麻扎—苏巴什蛇绿岩带、不同时期侵入岩、火山岩的大地构造环境的判别,论文确立了西昆北洋和西昆中洋两个大洋的存在。西昆北洋位于塔里木地块及西昆中带之间,西昆中洋位于西昆中带和西昆南带之间。西昆北洋的存在时限是中元古代至海西期末。西昆中洋根据苏巴什蛇绿岩的年龄及岩石化学特征,认为其在海西期已经为成熟的大洋,闭合的时间为印支期末。根据两个大洋的确立,认为西昆仑造山带经历了内部造山和边缘造山过程,初步探讨了其动力学演化过程:1.古元古代基底形成;2.中元古代地块的裂解;3.加里东、海西期西昆北复合造山带形成;4.印支期西昆中带、西昆南带内部造山阶段;5.燕山、喜山期西昆南带边缘造山阶段。并确定了西昆仑的三条构造带的大地属性:西昆北带为加里东期、海西期复合造山带;西昆中带为基底隆起及加里东、海西、印支花岗岩带;西昆南带为羌塘地块。经研究,课题组研究认为西昆仑造山带的主攻矿种是铜、铁、金、铅锌、稀有金属,主攻的矿床类型有热水喷流沉积矿床、中低温热液矿床、矽卡岩型矿床、造山型金矿床等。西昆仑造山带的区域成矿规律可以总结为:时间上,以海西期、印支期为主要成矿时代,海西期主要矿床有阿克塔什块状硫化物铜矿床、萨洛依块状硫化物铜矿床、特格里曼苏生物化学沉积铜矿床等;印支期主要矿床有矽卡岩型班迪尔铜矿床、色尔洪铜铁矿点等;其次是加里东期和元古代,加里东期的主要矿床有热水喷流沉积型切列克其菱铁矿床和黑恰菱铁矿床;元古代为沉积变质型老并铁矿床;而燕山期成矿较弱。空间上,成矿带呈带状分布,可以分为西昆北Cu、Pb、Zn、Au、Fe成矿带、西昆中Cu、Mo、Au、Fe(Co)、W、Sn成矿带、西昆南Fe(Co)、Mn、Au、Sb、Ag、稀有金属成矿带。论文在吉林大学地球科学学院地质流体实验室采用Linkam THSM-600型冷热台的进行了大量的流体包裹体测试,确定了各典型矿床(点)成矿流体的均一温度、盐度、密度、压力,并计算了成矿的深度,为西昆仑造山带的研究工作积累了大量的资料。热水喷流沉积型菱铁矿床包裹体均一温度为中低温(切列克其191.6-380℃;黑恰168-176℃),成矿流体具有高(中)盐度(切列克其32.93-34.52%(NaCl);黑恰6.72—11.38%(NaCl)),中(低)等密度(切列克其1.09-1.1g/cm~3;黑恰0.93—0.98 g/cm~3)的特点。古海水深度分别为2.19km(切列克其),1.83km(黑恰)。西昆仑造山带的造山型金矿化点包裹体均一温度低(帕西木125.1-168.3℃,叶尔羌149-165℃),矿化点流体具有低盐度(帕西木0.87-3.37%(NaCl);叶尔羌1.05-1.22%(NaCl)),低密度(叶尔羌0.92-0.93 g/cm~3;帕西木0.93-0.96 g/cm~3)的特点,成矿深度浅(0.9-1.0km)。西昆仑造山带的中低温热液脉型矿床包括卡兰古铅锌矿床和布斯拉津铜钼矿化点的流体包裹体均一温度低(卡兰古160—180℃;布拉斯津148.2—185℃),流体有中低盐度(卡兰古1.39—15.55%(NaCl);布斯拉津6.29-7.30%(NaCl)、低密度(卡兰古0.85—1.03 g/cm~3;布斯拉津0.93-0.97 g/cm~3)的特点,成矿深度浅(1.48km)。西昆仑造山带的矽卡型矿床受印支期花岗闪长岩和中酸性斑岩和石炭系大理岩联合控制。流体包裹体均一温度为200～240℃,矿床的流体盐度从早期至晚期由高变低(0.87～33.04%(NaCl)),流体低密度(0.92～1.0 g/cm~3),成矿深度浅(1.57km)。本次研究对三个矿区内的岩体进行了LA-ICP-MS锆石U-Pb年龄的测定,分别确定了色尔洪矿区内花岗闪长岩年龄为240.6±1.4Ma,斯如伊迭尔金铅锌多金属矿化点区内花岗闪长岩年龄12.86±0.88Ma。布斯拉津矿区内细粒花岗岩和闪长岩年龄分别为449±2.3Ma和446±2.1Ma。论文对布斯拉津辉钼矿进行了Re-Os测年,年龄为434.1±4.6Ma—441.4±2.1Ma。论文剖析了典型矿床的地质特征,结合本次流体包裹体研究获得的成矿温压等数据,以及部分矿区内测得的岩体及矿石年龄的数据,确定了矿床的不同成因类型。包括热水喷流沉积型矿床—切列克其铁矿床、黑恰铁矿床;矽卡岩型矿床—色尔洪铜铁矿点;生物化学沉积型矿床—特格里曼苏铜矿床;中温热液脉型矿床—卡兰古铅锌矿床、布斯拉津铜钼矿化点;造山型金矿床—叶尔羌金矿点、帕西木金矿化点,并建立了不同类型矿床的成因模式。论文对西昆仑造山带全区的15景TM、ETM+遥感图像研究,通过遥感图像的构造解译,划分出三个构造带和造山带各次级线形及环形构造,并运用ENVI及ERDAS等软件对遥感图像提取铁染及羟基等矿化蚀变信息。并分析了构造与找矿、矿化及蚀变信息与找矿之间的关系。最后,论文采用遥感矿化、蚀变信息与地质、化探等综合信息,对西昆仑造山带进行了以矿床成因类型为主的成矿远景区的划分,共圈出了13个A级远景区,25个B级远景区,21个C级远景区。矿床成因类型包括热水喷流沉积型矿床、与岩体有关的中低温热液脉型矿床、矽卡岩型矿床,块状硫化物型矿床、沉积变质型矿床等。并指出找矿潜力西昆南带>西昆北带>西昆中带。更多还原

【Abstract】 Western Kunlun belt, one of most important polymetallic metallogenic belts in China, is located in the north margin of Qinghai-Tibet plateau, south of Tarim basin where there are lots of mineral resources.Based on the study on the distributing of the intrusions of different stages and two ophiolite belts which were Kudi-Qimanyute and Mazha-Subashi ophiolite belt, make sure the presence of the two oceans. They are North Ocean of Western Kunlun between Tarim massif and middle of Western Kunlun belt and Middle Ocean of Western Kunlun between middle of Western Kunlun belt and south of Western Kunlun belt. The existence of the North Ocean of Western Kunlun is from Mesoproterozoic to Hercynian. Based on age and chemical characteristics of rocks of Subashi ophiolite, Middle Ocean of Western Kunlun was considered as a matured ocean during the period of Hercynian, closed in the end of Indosinian.According to the establishment of the two oceans, it was considered that Western Kunlun orogenic belt has experienced interior and peripheral orogenic stage, and its dynamic evolution is determined:1.the formation of basement in Paleoproterozoic; 2. plate lysis in Mesoproter-ozoic; 3.formation of North of Western Kunlun belt which is Caledonian and Hercynian complex orogenic belt; 4. stage of interior orogen between middle of Western Kunlun belt and south of Western Kunlun during the periods of Indosinian; 5. stage of peripheral orogen south of Western Kunlun belt during the periods of Yanshan and Himalayan. And identified the three western Kunlun tectonic belt: North of Western Kunlun belt is Caledonian and Hercynian composite orogenic belt; Middle of Western Kunlun belt is basement uplift and the granites of Caledonian, Hercynian, Indosinian; South of Western Kunlun belt is Qiangtang block.According to the study, we believe that the main minerals of the Western Kunlun orogenic belt are copper, iron, gold, lead, zinc and precious metals,and the main types of deposits are sedimentary exhalative deposits, medium-low temperature hydrothermal deposits, skarn-type deposits,orogenic gold deposits and so on. The regional metallogenic regularity in Western Kunlun orogenic belt can be summarized that the period of Hercynian and Indosinian were the main ore-forming age. Deposits in Hercynian are mainly Aketasshi massive sulphide copper deposits, Saluoyi massive sulfide copper deposit, Tegelimansu biochemical sedimentary copper deposits, etc. The main deposits in Indosinian are Bandier skarn copper deposit and Seerhong skarn copper iron Mineralization spots. Caledonian and Proterozoic are the second important ore-forming periods.The main deposits in Caledonian are Qieliekeqi and Heiqia siderite deposits which are sedimentary exhalative deposits. In Proterozoic formed Laobing Proterozoic sedimentary Metamorphic iron deposit. The mineralization is weak during the period of Yanshanian. Zonal distribution of ore belt can be divided into Cu, Pb, Zn, Au, Fe metallogenic North of Western Kunlun belt, Cu, Mo, Au, Fe (Co), W, Sn metallogenic Middle of Western Kunlun belt, Fe (Co), Mn, Au, Sb, Ag rare metal metallogenic South of Western Kunlun belt.During the period of writing the paper a lot of fluid inclusions tests were made, using Linkam THSM-600-type cold-hot desk in the laboratory of geological fluids of the college of the Earth Sciences, Jilin University. We got a lot of results of ore-forming fluids homogenization temperature, salinity, density and pressure, and we calculated the depth of mineralization of the typical deposits. The results accumulated large amounts of data for the Western Kunlun orogenic research.Homogenization temperatures of fluid inclusions in the sedimentary exhalative deposits are medium and low(Qieliekeqi 191.6-380℃; Heiqia just 168-176℃). Ore-forming fluid has a high (or moderate) salinity (Qieliekeqi 32.93-34.52% (NaCl); Heiqia just 6.72-11.38% (NaCl)), moderate (or low) density characteristics (Qieliekeqi 1.09-1.1g/cm~3; Heiqia 0.93-0.98 g/cm~3). Ancient water depth was 2.19km (Qieliekeqi), 1.83km (Heiqia).Homogenization temperatures of fluid inclusions in Western Kunlun orogenic gold mineralization plots is low(Paximu 125.1-168.3℃, Yeerqiang 149-165℃), mineralization fluid with low salinity (Paximu 0.87-3.37% (NaCl); Yeerqiang 1.05-1.22 % (NaCl)), low density characteristics (Yeerqiang 0.92-0.93 g/cm~3; Paximu 0.93-0.96 g/cm~3), ore-forming depth is shallow (0.9-1.0km).Homogenization temperature of fluid inclusions in the medium-low temperature hydrothermal deposits which include Kalangu lead-zinc deposit and Busilajin copper-molybdenum mineralization plots is low (Kalangu 160-180℃; Busilajin 148.2-185℃), with moderate to low salinity (Kalangu 1.39-15.55% (NaCl); Bulasijin 6.29-7.30% (NaCl)), and low density characteristics (Kalangu 0.85-1.03 g/cm~3; Busilajin 0.93-0.97 g/cm~3). Ore forming depth is shallow (1.48km).In Western Kunlun orogenic belt, skarn-type deposits are controlled by the Indo-granodiorite and intermediate-acid porphyry and Carboniferous marble. Fluid inclusion homogenization temperature is from 200℃to 240℃. From early to late stage, fluid salinity decreased (0.87 ~ 33.04% (NaCl)); fluid shows low density (0.92 ~ 1.0 g/cm~3), and shallow depth (1.57km).According to the study of U-Pb zircon by LA-ICP-MS, the age of three rocks was respectively determined.1.The age of granodiorite in Seerhong deposit is 240.6±1.4Ma;2. The age of granodiorite in Siruyidieer lead-zinc mineralization plots is12.86±0.88Ma;3. The age of fine-grained granite and diorite in Bujinlasi deposit is 449±2.3Ma and 446±2.1Ma. According to the result of molybdenite Re-Os dating, the age of Busilajin Molybdenum deposit is 434.1±4.6Ma-441.4±2.1Ma.On the basis of the geological studies above, combining with the results of the study of fluid inclusions, and the age of the intrusions and ore in deposits, different genetic types of deposits were determined. Including sedimentary exhalative deposits– Qieliekeqi iron ore deposits and Heiqia iron deposits; skarn-type deposit Seerhong copper iron mineralization plot, biochemical sedimentary deposits– Tegelimansu copper deposit; the hydrothermal vein type deposits - Kalangu zinc-lead deposit and Busilajin copper-molybdenum mineralization plot; orogenic gold deposits -Yeerqiang and Paximu gold mineralization point. In the end, we established the genetic models of different types of deposits.15 TM, ETM + remote sensing images of Western Kunlun orogenic belt were studied in the paper. According to the construction interpretation of remote sensing image, three tectonic belts and the secondary line and ring structures of orogenic belt were divided. By using the software of ENVI and ERDAS to remote sensing image, extraction such as iron mineralization and hydroxyl alteration information are made. And analyses the relationship of structure and exploration, of mineralization-alteration information and exploration.In the end, according to the remote sensing mineralization, alteration, geology geochemical and other comprehensive information, we devided Western Kunlun orogenic belt metallogenic perspective by origin type of the deposits, including 13 A leve prospect areas, 25 B level prospect areas and 21 C level prospect areas. Genesis types include sedimentary exhalative deposits, medium-low temperature hydrothermal vein-type deposits and skarn-type deposits which are related to intrusions, massive sulfide deposit, sedimentary-metamorphic deposits, and so on. The results are as followings: South of Western Kunlun is the best potential prospecting region; the second is North of Western Kunlun; the least is Middle of Western Kunlun.更多还原