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峨嵋山大岩浆省由大量的溢流玄武岩及其伴生的镁铁和超镁铁侵入岩组成。攀西地区的一些层状辉长岩体形成于260Ma,与早期报道的峨嵋山大岩浆省的年代相同。这些岩体中含有巨大的钒钛磁铁矿床,矿体呈似层状及透镜状产在层状辉长岩体的下部层位,不同于典型的层状岩体(如布什维尔德岩体)的磁铁矿床。地球化学资料表明,攀西地区含磁铁矿的岩体是从高度演化的基性岩浆中结晶而成,因为富硅的岩浆分离使得母岩浆高度富集铁、钛和钒。相对围岩来说,磁铁矿石形成较晚,是从氧化物矿浆中结晶的产物。矿石中有丰富的含水矿物相,流体的参与对氧化物矿浆的形成有重要的作用。
The Emei Mountain large magmatic province consists of a large number of overflow basalts and associated mafic and ultramafic intrusive rocks. Some of the layered gabbro bodies in the Panxi area formed at 260 Ma, the same age as the earlier reported Emei Mountain Magma province. These rock masses contain a huge vanadium-titanium magnetite deposit. The orebodies are stratified and lenticular in the lower layer of layered gabbro, which is different from the typical layered rock mass (such as the Bushwild rock mass) Magnetite deposit. Geochemical data show that magnetite-bearing rock masses in Panxi are crystallized from highly evolved basic magmas because the magmatic separation enriched in silicon makes the parent magma highly enriched in iron, titanium and vanadium. Relative to the surrounding rock, the magnetite ore is formed late, is the product of crystallization from the oxide slurry. Ore is rich in water-bearing mineral phase, the fluid involved in the formation of oxide ore has an important role.