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通过对中甸峨眉山玄武岩中超基性—基性岩包体的岩相学、电子探针、扫描电镜和能谱分析,发现在光学显微镜下呈黑色不透明的物质,在电子显微镜下表现为硅酸盐和尖晶石族氧化物为主的超显微隐晶—非晶质集合体。结合超微晶矿物晶体化学和元素地球化学分析认为,该物质是一种具熔浆和超临界性质及地幔流体属性的富铁(微晶)玻璃,是深部地质过程中,包含于幔源岩浆并与其同步运移但互不混熔的地幔流体作用遗留的微观踪迹物质。该地幔流体在伴随幔源岩浆的结晶成岩过程中,表现出由硅酸盐→尖晶石→磁铁矿→铬铁矿→钛铁矿的熔离作用,并相应触发主岩和包体岩石的交代蚀变和金属矿化,是推动和引发地壳中成岩成矿的重要动力源和物质源。由此进一步认识到,滇西地区上地幔发育峨眉地幔柱活动,为该区二叠纪之后的不同部位和不同矿种的内生多金属成矿提供了有利的深部地质背景条件。
By means of petrography, electron probe, SEM and EDS analysis of the ultrabasic-basic rock inclusions in Emeishan Basalts in Zhongdian County, it was found that the material which is black and opaque under optical microscope shows silicic acid under the electron microscope Salt and spinel-based superfine cryptocrystal-amorphous aggregates. Based on the crystallographic and elemental geochemical analyzes of ultrafine-crystalline minerals, it is considered that this material is an iron-rich (microcrystalline) glass with magmatic and supercritical properties and mantle fluid properties. It is a component of deep-geological processes that include mantle-derived magmas And with its migration of migration but not mixed with the mantle fluid left behind by the micro-trace material. The mantle fluid during the process of crystalline diagenesis accompanied with mantle magma shows the melting of silicate → spinel → magnetite → chromite → ilmenite and correspondingly triggers the formation of host rock and enclave rock The explanation of alteration and metal mineralization is an important source of power and material for the promotion and initiation of diagenetic mineralization in the crust. Therefore, it is further recognized that the development of Emei mantle plume in the Upper Mantle of western Yunnan provides favorable deep geological background conditions for endo-polymetallic mineralization of different parts and different mineralizations in the area after Permian.