【作者】 赵海滨；

【导师】 莫宣学；

【作者基本信息】 中国地质大学（北京） ， 矿物学、岩石学、矿床学， 2006， 博士

【摘要】 西南“三江”位于特提斯与环太平洋两个巨型造山带的结合部,是欧亚、印度、太平洋板块三大巨型板块相互作用的交汇地区,经历了从特提斯形成演化到印度-欧亚大陆碰撞、高原隆升的复杂演化历史。复杂的地质构造环境,形成了该区丰富的矿产资源,成为我国最重要的有色金属与贵金属矿产资源基地之一,也是世界规模的特提斯成矿域的重要组成部分。兰坪盆地位于“三江”造山带的中段,夹持于金沙江断裂带与澜沧江断裂带之间,经历了从晚三叠世到早白垩世弧后盆地-前陆盆地阶段及新生代走滑拉分盆地阶段的演化。此过程形成了铅、锌、铜、银等金属的巨量富集,其中产出有世界级的金顶超大型铅锌矿床,是“三江”成矿带中一个国内外瞩目的金属富集区。其主要成矿作用是在印度板块与欧亚大陆碰撞的大背景下发生的,主要矿床类型为热水沉积改造型矿床,主要成矿时代在始新世-早中新世(约56-21Ma)。喜马拉雅期兰坪盆地东缘的金沙江断裂、西缘的澜沧江断裂和位于盆地中央的“中轴断裂”是本区与深部相连的主要的导矿构造,盆地热卤水的循环和深部含矿流体的上升,均以这些深断裂带作为上升通道。上三叠统三合洞组(T3s)、中侏罗统花开佐组(J2h)、下白垩统景星组(K1j)和南新组(K1n)是区内的重要的矿源层。碳酸盐岩和砂岩是区内重要的赋矿岩石。碳酸盐岩中特别富集元素有Co、Ba、Sc,富集元素有Cu、Pb、Zn、As、Sb等17种元素;砂岩中特别富集元素为Co、Ni、Sb、Sc、Mn、Ba、Th,富集元素有Cu、Pb、Zn、V、P、As等13种元素。对矿石矿物和脉石矿物的地球化学、稳定同位素、放射性同位素和流体包裹体研究显示,兰坪盆地成矿物质具有多来源的特点,既有盆地内浅源地层物质,又有深部物质的参与,流体中既有盆地卤水、大气水,又有岩浆水。兰坪盆地中岩浆岩出露不多,但对有限的岩浆岩露头的研究表明,成矿作用与岩浆岩活动可能有较密切的关系,成矿作用时代与岩浆活动时代相近。本次工作在金顶矿床附近新发现有云煌岩,进一步证实了前人认为兰坪盆地深部有隐伏侵入体存在的推测。岩浆活动为成矿物质的活化提供了热源和部分成矿物质。兰坪盆地可划分东、西两个成矿带。以兰坪—思茅断裂(中轴断裂)为界,东矿带以银、铅、锌为主,西矿带以铜、钴为主。这种矿床的分带性,主要是由不同的矿源层、不同的成矿流体系统、不同的深部壳幔结构、不同的地球化学块体造成的不均一形成了东、西成矿元素的差异。总结区域成矿模型,大致可分为两个阶段,第一阶段矿源层的形成,盆缘岩石特别是更多还原

【Abstract】 Sanjiang area is located at the junction between two giant orogenic belts, the Tethyan and the Circum-Pacific, and affected by the convergence of Eurasian, Indian and Pacific three plates. It has a complicate history from the formation and evolution of the Tethys to India-Eurasia collision and uplift of the plateau. The complicate tectonic settings result in abundant mineral resources. The Sanjiang metallogenic belt thus becomes one of the most important bases of mineral resources for precious and base metals in China, and also an integrate part of the world-scale Tethyan metallogenic belt.Lanping basin is located in the middle part of the Sanjiang orogenic belt between the Jinshajiang fault and the Lancangjiang fault zones. It underwent a two-stage evolution, that is, the stage of back-arc basin / foreland basin from middle Triassic to early Cretaceous, and the stage of slip pull-part basin in the Cenozoic. Huge accumulation of metals such as lead, zinc, copper and silver took place during this process and formed a well-known metal-concentrated region, including the formation of the Jinding world-class super-giant Pb-Zn deposit.Mineralization took place mainly in tectonic settings of India- Eurasia collision in the period from Eocene to early Miocene (about 56-21 Ma). The main type of ore deposits are hydrothermal sedimentary rework type. Himalayan Jinshajiang fault and Lanchangjiang fault on both side of the basin and the“central-axial fault”in the middle of the basin played a role as passageway for ore fluids. These faults are the channels for the deep-seated thermal brine to move up. The upper Triassic Sanhedong formation (T3s) consists of carbonate of shallow marine facies. The middle Jurassic Hakaizuo formation (J2h), lower Cretaceous Jingxing formation (K1j) and Nanxin formation (K1n) are composed of terrestrial red beds of clastic rocks. These formations are main host rocks for ores. The carbonate layer is rich in 17 elements such as Cu, Pb, Zn, As, Sb and so on, especially rich in Co, Ba and Sc. The sandstone is rich in 13 elements, such as Cu, Pb, Zn, V and P, especially in Co, Ni, Sb, Sc, Mn, Ba and Th. Studies in geochemistry, stable and radiogenic isotopes of ores, gangues and fluid inclusions suggest that mineralization in Lanping basin is characterized by multiple sources for metals, from either the strata in the basins or deep in the Earth’s interior. Ore-forming fluids consist of brine in the basin, meteoric water and magmatic fluid.Study on limited outcrops of igneous rocks in the basin suggests that mineralization may somewhat be related to magmatism, although only few igneous rocks crop out within the basin. The ages of mineralization are nearly coeval to those of emplacement of igneous rocks. A minette dike was found near Jingding deposit in this work, confirming inferred hidden intrusions更多还原