复合成矿系统理论:揭开西南特提斯成矿之谜的关键

本文总结了"三江特提斯复合造山与成矿作用"和"中国西南特提斯典型复合成矿系统及其深部驱动机制"两轮国家重点基础研究发展规划项目研究进展及其重大突破,主要内容包括以下四个方面:(1)构建了西南特提斯从原特提斯、古特提斯、中特提斯到新特提斯增生-碰撞造山演化模式,揭示复合造山与构造体制转换机制;(2)创建复合成矿系统理论体系,揭示复合造山带巨量金属富集机理。通过对西南特提斯成矿域典型矿床系统剖析,厘定了增生造山海底喷流型Cu-Pb-Zn-Ag、增生-碰撞造山岩浆热液型Cu-Mo-Sn-W、碰撞造山盆地卤水-热液型Pb-Zn-Ag-Cu和碰撞造山斑岩-矽卡岩型Au-Cu-Mo四类复合成矿系统;(3)通过同位素地球化学、地球物理场和成矿系统等综合研究,分析了西南特提斯岩石圈结构以及大规模成矿作用,解析深部动力学机制和成矿机制;(4)构建矿床成因模式和勘查模型,理论指导找矿取得突破。

The theory of composite metallogenic system: Key of recovering metallogenic mystery in the SW Tethys

The recent research advances were summarized from the two National Basic Research Programs of China, including "The Superimposed Orogenesis and Metallogenesis in the Sanjiang Tethys" and "The Typical Composite Mineral Systems and Their Deep Driving Mechanism in the Tethyan Domain in SW China". The SW Tethys Orogen is one of the important branches of the eastern Tethyan Orogen, and thus it bears significance for the development of the Tethyan belt within Southeast Asia. This study is crucial for understanding the processes of superimposed orogenesis which led to the formation of the SW Tethys Orogen and recovering typical composite mineral systems and their deep driving mechanism. This paper also summarized recent important breakthroughs of these two programs as follows:(1) the accretionary-collisional evolution model and structural system transformation from Proto-Tethys, Palaeo-Tethys, Meso-Tethys to Neo-Tethys were proposed, and evolution process of the composite orogen were analyzed by a case of Changning-Menglian Tethys Ocean; (2) by analyzing typical deposits the Tethyan domain in SW China, the theoretical system of composite metallogenic system is established to reveal the mechanism of huge metal enrichment in composite orogenic belt, including accretionary orogenic VMS type Cu-Pb-Zn-Ag, accretionary-collisional orogenic magmatic-hydrothermal type Cu-Mo-Sn-W, collisional orogenic MVT-hydrothermal type Pb-Zn-Ag-Cu, and porphyry and collisional orogenic skarn Au-Cu-Mo deposits; (3) based on isotopic geochemistry, geophysical field, and mineral system, we have analyzed crustal architecture and large-scale mineralization, deep dynamics and metallogenic geodynamics of the Tethyan domain in SW China; and (4) the genetic model and exploration model of the deposit were constructed to guide the breakthrough in prospecting. This paper is not only useful for interpretation of the theory of composite metallogenic system but also significant for mineral exploration in the area especially for finding large deposits.