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青海南部存在着巨大的成矿潜力,研究该区的构造变形与成矿作用的关系,对于认识区内众多矿床(化)的构造背景和控矿要素具有重要意义。新生代的走滑断裂和逆冲推覆构造是大陆碰撞造山带成矿理论中晚碰撞阶段在青藏高原东、北缘的重要构造形式。走滑断裂呈北西向,控制着藏东一系列走滑拉分盆地和斑岩的产出;逆冲推覆构造走向北西,整体自南向北呈现很好的分带特征,可分为根带、中带和前锋带。研究区存在两种类型矿床,分别为走滑断裂控制的斑岩型矿床和逆冲推覆构造控制的热液型矿床。其中,切过地壳尺度的走滑断裂因减压作用导致含水地幔的部分熔融,进而导致富含挥发分的含矿斑岩上涌、侵位,形成纳日贡玛斑岩型钼(铜)矿;逆冲推覆作用是流体长距离迁移的动力来源,逆冲推覆构造前锋带的逆冲断层上(下)盘破碎带或次级断层附近是成矿流体迁移的疏导系统和金属汇聚、淀积的重要场所。
There is a huge potential for mineralization in southern Qinghai Province. Studying the relationship between tectonic deformation and mineralization in the area is of great significance for understanding the tectonic setting and ore-controlling elements of many deposits in the area. The Cenozoic strike-slip faults and thrust nappe structures are important tectonic forms in the eastern and northern margins of the late collision stage of the continental collision orogenic belt in the eastern and northern Qinghai-Tibet Plateau. The strike-slip faulting is northwesterly and controls the output of a series of strike-slip sub-basins and porphyries in the eastern Tibet. The thrust nappe structure moves to the northwest and presents a good zoning characteristic from south to north, Belt, belt and striker belt. There are two types of deposits in the study area, namely porphyry-type deposits controlled by strike-slip faults and hydrothermal deposits controlled by thrust nappe structure. Among them, the strike-slip faults crustally crushed by the depressurization result in the partial melting of the hydrous mantle, which leads to upwelling and emplacement of ore-bearing porphyries rich in volatile matter, resulting in the formation of the Nazigongma porphyry molybdenum (copper) ore . The thrust nappe is the source of long-distance fluid migration. The upper (lower) plate fault zone or the secondary fault near the thrust belt in the thrust nappe structure is the divergent system and metal convergence of ore-forming fluid migration. An important place to deposit.