中甸岛弧岩浆岩地球化学特征及斑岩型铜矿成矿研究

【作者】 刘学龙；

【导师】 李元； 李文昌；

【作者基本信息】 昆明理工大学 ， 构造地质学， 2009， 硕士

【摘要】 本文“中甸岛弧岩浆岩地球化学特征及斑岩型铜矿成矿研究”,是在云南省地质调查局承担的国家重点基础研究发展计划(973计划)项目：巨型矿床形成保存及资源潜力课题的资助下完成的。中甸岛弧位于西南三江构造火成岩带义敦岛弧南端,西以乡城-格咱深大断裂为界,东部和南部与甘孜-理塘结合带和扬子板块西南边缘相连,是晚三叠世甘孜-理塘洋壳向德格-中甸陆块俯冲的产物,为我国近年来新发现的重要铜多金属成矿带。该区强烈的构造-岩浆活动贯穿于岛弧造山作用的始终,丰富的成矿作用发育于岛弧造山的不同时代、不同环境,产出了普朗、雪鸡坪等大中型斑岩铜多金属矿床和矽卡岩型铜多金属矿床(红山),也形成了燕山期蚀变花岗岩-热液石英脉型钨、钼中型矿床(休瓦促和热林),构成了斑岩型、矽卡岩型和浅成热液型多类型多矿种的铜多金属成矿带。普朗斑岩型铜矿是印支期斑岩铜矿的典型代表,为近年来国内外众多学者所关注和研究。本文以中甸岛弧岩浆岩及普朗斑岩型铜矿床作为研究对象,在大陆动力学理论和多岛弧盆成矿论的指导下,以野外地质调查为基础,分析了中甸岛弧岩浆岩的时空分布规律,地球化学特征及与成矿的关系。应用Ar-Ar精确测年技术手段厘定了中甸岛弧侵入岩的时空分布关系,了解了不同构造体系构造-岩石组合分布与演化序列,研究了成岩成矿时代及成矿作用过程。采用了“岩石探针与地球化学示踪技术”。通过对不同时代、不同构造-岩浆系统的岩石地球化学的研究,探讨了岩浆源区,成岩成矿的大地构造背景,查明了普朗斑岩型铜矿的成矿作用过程及地球化学元素的时空演化和分布规律,并对中甸斑岩型铜矿的成矿模式进行了研究。更多还原

【Abstract】 The article, Arc magmatic rocks geochemical characteristics and porphyry copper deposit metallogeny research, is completed in funding from the subject of the National Basic Research Program of China(973 program):The formation of giant deposits in the preservation and resource potential, which was undertaken by Yunnan Geology Survey.Zhongdian arc located in the southern of Yidun arc of southwest Sanjiang tectonic igneous rock band. Western bounded by Xiangcheng-Geza deep faults, Eastern and southern connected to Ganzi-Litang suture zone and the southwestern edge of the Yangtze plate, It is a product of Ganzi-Litang oceanic crust diving to the Zhongdian Landmass in late Triassic and the importance of China’s newly discovered copper-polymetallic metallogenic belt in recent years. The region strong tectonic magmatic activity throughout the island island-arc orogenesis from beginning to end, Rich mineralization developed in the different times and in different circumstances of island arc orogenesis, which ouputed the super-large-medium sized Pulang and Xuejiping porphyry copper-polymetallic deposit in Indosinian, bred the skarn-type polymetallic deposits(Hongshan),and also formed Yanshanian altered granite-hydrothermal quart vein type tungsten, molybdenum medium-sized deposit(Xiuwacu and Relin), constituted porphyry, skarn and epithermal multi-type and multi-minerals copper-polymetallic metallogenic belt.Pulang porphyry copper deposit is typical representative of the Indosinian porphyry copper deposit,that concerned and researched by many scholars at home and abroad in recent years.This paper, Zhongdian island arc magmatic rocks and the Pulang typical porphyry copper deposit, as a object of study, under the guidance of continental dynamics theory and Multi-mineralization theory of island arc and basin, analysised temporal and spatial distribution of of island arc magmatic rocks in Zhongdian based on the geological survey, geochemical characteristics and relations to mineralization. Use the Ar-Ar accuracy dating technology to determine the Zhongdian island arc intrusive rocks in the relationship between spatial and temporal distribution, understanded the different tectonic system structure-distribution and evolution of rock sequences, studied the diagenetic ore-forming epoch and the mineralization process. Adopted the probe rocks and geochemical tracer technology.Through the studying rocks geochemical of different times and different tectonic-magma system, discussed the magma source region, diagenetic mineralization tectonic setting,identified mineralization process of Pulang porphyry copper and geochemical elements’the evolution and distribution of spatial and temporal,and studied the metallogenic model of Zhongdian porphyry copper deposit.更多还原