【作者】 黄震；

【导师】 岳书仓； 徐晓春；

【作者基本信息】 合肥工业大学 ， 矿物学岩石学矿床学， 2005， 博士

【摘要】 云南澜沧江火山-侵入岩带位于云南省西部澜沧江流域中南段,兰坪盆地和思茅盆地之西缘,范围包括自兰坪到思茅的沿澜沧江河谷及两岸大致呈南北向分布的狭长地带。该区区域构造、岩浆作用及成矿条件复杂,有着良好的铜成矿背景,现已发现有近200处的铜多金属矿床（点）,是我国西南铜、银、多金属矿集区的重要组成部分。因此该区自“七五”和“八五”以来一直是地质矿产部门非常重视的重点矿业资源调查、勘探及开发区。 论文工作根据研究区自然地理条件和以往工作基础,采取突出重点、集中突破的方式,认真进行了野外区域路线踏勘和矿床、矿点的地质观察和研究,对区域相关火成岩进行了认真取样,并选择科登涧、金满、水泄、宋家坡4个代表性矿床作重点研究,系统地采集了大量的矿区岩石和矿石标本,并选取合适的地质样品进行相关的测试与分析,在此基础上,结合前人研究成果进行综合理论分析和探讨。论文取得的主要成果和创新认识如下: 1、根据云南澜沧江火山-侵入岩带岩石化学和地球化学研究,认真分析了区域构造-岩浆演化,赞同朱勤文等（1991;1993）和莫宣学等（1993;1998）的观点,初步认定:昌宁-孟连带的洋脊/洋岛型火山岩、蛇绿岩与南澜沧江火山-侵入岩（南澜沧江弧火山岩带及临沧-勐海花岗岩带）,共同构成了成对分布的洋脊火山岩-蛇绿岩-弧岩浆带,昌宁-孟连带是古特提斯主洋盆残迹,南澜沧江带是该洋盆向东俯冲形成陆内造山运动的产物。 2、云南澜沧江火山-侵入岩带中的中三叠世火山岩以酸性岩为主,岩石微量元素和稀土元素显示该火山岩具有岛弧性质。地层学及Sm-Nd同位素地质年代学研究表明,其成岩年龄（228±56Ma）与区域（西带）大规模花岗岩基的侵入时代（190～240Ma）（王义昭等,2000）大体同时,反映中三叠世特提斯洋已经闭合、陆块发生碰撞俯冲作用,在总体挤压的背景下局部发生拉张,澜沧江断裂再次活动,致使深部物质熔融,沿断裂带上涌、喷发,因此该火山岩应为“后碰撞型”岛弧火山岩。 3、云南澜沧江火山-侵入岩带铜多金属矿床发育,综合分析和对比区域矿床地质及分布特征显示,该带北段和南段明显不同。北段兰坪盆地西缘主要发育脉状铜多金属矿床,受澜沧江断裂带控制明显,赋矿围岩为二叠系至第三系,主要是由下二叠统经上三叠统到上侏罗统砂岩、粉砂岩和页岩组成的碎屑岩建造、火山岩建造及含盐红色碎屑岩建造,矿体主要以脉状或透镜状产出;南段思茅盆地西缘铜多金属矿床类型多样,既发育赋存于沉积地层中的脉状矿床,也发育赋存于火山-次火山岩体中的浸染状、细脉浸染状斑岩型矿床,还发育火山-沉积岩系中的层状、似层状块状硫化物矿床。 4、区域脉状铜多金属矿床成矿流体包裹体地球化学研究表明,其成矿流体包裹体类型简单,以液相和气液两相包裹体为主:均一温度不高,显示成矿为中低温度;流体包裹体成分显示为Na⁺+（K⁺）+Ca²⁺+Cl^-+SO₄^2-型,表明成矿流体主要是以大气降水补给的热卤水:成矿流体气相组成主要为H₂O和CO₂,还原性烃类气体的存在并与氧化性气体的反相关关系显示其与盆地有机质的密切关系及其在成矿过程中的重要性。结合成矿地质背景、矿床地质特征及矿床矿物氢氧同位素的分析,认为该带中的矿床成矿物质来源复杂,主要是深循环的大气降水对相关岩石的淋滤萃取,可能有地幔物质参与成矿,但是次要的,成因上应为受深断裂控制的、大气降水补给的热卤水型矿床。 5、云南景谷宋家坡铜矿床产于英安斑岩体及其围岩中三叠统火山岩地层中,矿床原生矿化相对较弱,次生硫化物富集,地表氧化强烈。矿床地质及同位素地质年代学研究表明,宋家坡铜矿床的成矿作用与赋矿英安斑岩的成岩作用关系密切、时间相近,原生矿化属斑岩型铜矿化;而且,该矿床成矿经历了后期盆地热卤水的淋滤富集和表生氧化作用的改造。从全球构造上看,宋家坡斑岩型铜矿床位于特提斯-喜马拉雅铜矿带这一全球性的斑岩铜矿带上,更多还原

【Abstract】 Lancangjiang volcanic-intrusive rock belt lies in the middle southern segment of the western Yunnan province, the middle Lancangjiang River, the western border of the Lanping basin and the Simao basin, whose range includes the narrow and long zone of the stream-valley along the Lancangjiang River form Lanping to Simao of Yunnan province which almost presents the southern-northern direction. The region is complicated in geological structure, magmatism and mineralization conditions, which has the good copper mineralization background. Almost 200 copper-polymetallic ore deposits have been found by now. It is also the important component of the southwestern copper, silver-polymetallic deposits concentration area in China. So it is taken into account by the Ministry of Geology and Mineral Resources of China as the important zone of the mineral resource survey, exploration and developing region.This work for the degree of Doctor of Philosophy was based on the natural geographical conditions of the region and the achievements in scientific research of the former. The field work’s method was making the importance clearly and concentrating power to breakthrough difficult questions. The reconnaissance of the field regional geological line and spots as well as the observation and researching of the mineral deposits were carefully carried through. The regional igneous rocks were carefully sampled. And four representative mineral deposits were chosen for emphatic researching, which are Kedengjian, Jinman, Shuixie and Songjiapo. A lot of magmatic rocks and ores specimens were systematically picked up, and the suitable geological samples were chosen for relevant test and analysis. Based on these above, combining the scientific productions for synthetic-theoretical analysis and probing of the former people, the major outcomes and innovational cognitions are as follows:1. In accordance with the lithochemistry and the lithogeochemical studies of the Lancangjiang volcanic-intrusive rock belt of Yunnan province, the regional tectonic-magmatic evolution has carefully discussed in the paper. The author agrees with the standpoints of Zhu Qinwen et al (1991; 1993) and Mo Xuanxue et al (1993; 1998), and mainly considers that the volcanic rocks of the oceanic ridge / oceanic island type and the ophiolites in Changning-Menglian belt and the volcanic-intrusive rocks in the southern Lancangjiang belt (the arc volcanic rock belt in the southern Lancangjiang River and the granite belt in Lincang-Menghai), jointly form the volcanic rocks of oceanic ridge-ophiolite-arc magmatic rock belt distributing in couples. Changning- Menglian belt is the vestiges of the major oceanic basin of the paleo-Tethy, the southern Lancangjiang belt is the product of orogenic movement in intracontinent that the oceanic basin dived to the crust of the east of the basin.2. The middle Triassic volcanic rocks in the volcanic-intrusive rock belt of Lancangjiang River are the acid rocks in majority. The geochemical studies of trace element and the rare earth element indicate the volcanic rocks are similar to island arc volcanic rocks. The research of the stratigraphy and the Sm-Nd isotopic geochronology show that diagenetic age of the volcanic rocks (228±56Ma) and the intrusive epoch of the regional (the western belt) large scale granite batholith (190~240Ma) (Wang Yizhao et al, 2000) are simultaneous roughly. This reflects the Tethyan ocean in the middle Triassic period had closed, the landmass had occurred collision and subduction. At the background of compression in overall, pull-apart in local, the Lancangjiang fault moved again, which made the anatectic magma product, upwelled and erupt along the faulted zone. So the volcanic rocks shouldbe the "post-collision type" island arc volcanic rocks.3. The copper-polymetallic ore deposits are widely distributed in the Lancangjiang volcanic-intrusive rock belt of Yunnan province. Synthetical analysis and constasting of the regional ore deposits geological characteristics and distribution regularities of the belt show that the n更多还原