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作者对由古生代基底和一些火山沉积盆地组成的法国中央地块西北部不同的Au-As-Sb矿化剪切带进行了矿物学、地球化学、流体包裹体(微地热温标和拉曼光谱分析)以及稳定同位素研究。结果表明,从早期脆性变形阶段到温度最低的晚期水热活动阶段,在裂隙带中有多期流体循环,其中晚期以大气降水流体渗透为主。在大部分矿床中,原来主岩的矿物(石英、斜长石、正长石,黑云母土绿泥石)依次转化为下列以钾云母为主的矿物组合:(1)白云母-石英-锐钛矿;(2)石英-多硅白云母-铁白云石;(3)石英-伊利石-铁白云石。在Villeranges矿床,对新鲜岩石和蚀变岩石作了物质质量平衡计算,并进行了物质迁移的模拟。其结果表明,在成矿期,热水流体含有H_2O、CO_2、S和(Au、Sb),并在蚀变时进入岩石,岩石则释放出Na、Ba、Sr,与此同时,Si、Fe、Ca、Mg、Al、Ti和K在本来位置上重新组合形成石英、铁白云石、钾云母、铁钛矿、黄铁矿和方解石。根据fo_2—fs_2—PH—T—P资料和物质迁移计算的结果,对水热系统作了总体恢复。
The authors performed mineralogical, geochemical, and fluid inclusions of different Au-As-Sb mineralized shear zones in the northwestern part of the French central mass consisting of Paleozoic basalts and volcanic sedimentary basins (microthermal geothermal and Raman spectroscopy ) And stable isotope studies. The results show that there are many periods of fluid circulation in the fracture zone from the early stage of brittle deformation to the late stage of hydrothermal activity with the lowest temperature, of which the fluid infiltration is mainly dominated by the precipitation in the late stage. In most of the deposits, the minerals of the original host rock (quartz, plagioclase, orthoclase and biotite chlorite) are successively converted into the following mineral assemblages based on potassium mica: (1) muscovite-quartz- Anatase; (2) Quartz-polysiliciferous-iron dolomite; (3) Quartz-illite-iron dolomite. In the Villeranges deposit, the mass balance of fresh and altered rocks was calculated and the material migration was simulated. The results show that the hydrothermal fluid contains H_2O, CO_2, S and (Au, Sb) during the mineralization period and enters the rock during the alteration, while Na, Ba and Sr are released from the rock. At the same time, Si, Fe , Ca, Mg, Al, Ti and K are recombined at their original positions to form quartz, iron dolomite, kalium, ferrotitanium, pyrite and calcite. According to the results of fo_2-fs_2-PH-T-P data and material migration calculation, the hydrothermal system was restored.