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Kosice矿床是斯洛伐克第二大的菱镁矿床(150Mt),位于Gemeric的东部。其镁质碳酸盐矿体赋存于石炭纪石灰石和含白云石的石灰石中,同时下盘黑色片岩中也含有被铁质碳酸盐交代的薄层碳酸盐透镜体。在华力西期造山运动(M1)中,古生代岩石受到了低级变质作用(绿泥石带)。镁交代作用始于白云岩1的结晶作用,其后形成菱镁矿,最终沿裂隙形成铁菱镁矿。铁质碳酸盐包括早期铁白云石-白云石,铁白云石和后期含方解石和石英的菱铁矿。根据碳酸盐矿物对地质温度计,白云石1结晶作用发生在300~340℃。这一结果与M1的变质矿物组合(绿泥石,白云母-伊利石)吻合。铁白云石的结晶作用发生在320~370℃.少量细脉中可见白云石2,绿泥石和伊利石-多硅白云母,它们是由于阿尔卑斯期造山运动M2变质作用形成的更晚的矿物组合。 菱镁矿的流体包裹体(FI)研究,显示存在不同成分的热卤水,卤水成分变化相当于NaCl含量21~42wt％,但其它成分的盐含量高于NaCl,溶解的CO2含量也有变化。两相包裹体均一温度(Th)的范围为164~217℃,含石盐子晶包裹体均一温度的范围为217~344℃。富CO2包裹体(盐度相当于NaCl含量1-22wt％,CO2的密度为0.28~0.77 g·cm-3,均一温度为289~344℃)在菱镁矿中是次要的,但这种包裹体在与矿石伴生的石英中是主要的,并且与含石盐
The Kosice deposit is Slovakia’s second largest magnesite deposit (150Mt), located in the eastern part of Gemeric. The magnesian carbonate orebodies occur in Carboniferous limestone and dolomite-containing limestone, while the lower plate black schist also contains thin carbonate lens bodies that are replaced by iron carbonate. Paleozoic rocks were subjected to low-grade metamorphism (chlorite belt) in the Wahleysian orogeny (M1). Magnesium metasomatism began with the crystallization of dolomite 1, followed by the formation of magnesite and eventually the formation of iron magnesite along the fracture. Iron carbonates include early iron dolomite-dolomite, iron dolomite and later siderite containing calcite and quartz. According to the carbonate minerals on the geothermometer, the crystallization of dolomite 1 occurs at 300-340 ° C. This result is consistent with the metamorphic mineral assemblage of M1 (chlorite, muscovite-illite). The crystallization of iron dolomite occurs at 320- 370 ° C. Dolomite 2, chlorites and illite-polysilicites are visible in a few fine veins, which are later mineral assemblages due to M2 metamorphism in the Alpine orogeny . Magnesite fluid inclusions (FI) study shows that there are different compositions of hot brine, brine composition changes equivalent to NaCl content of 21 ~ 42wt%, but other components of the salt content is higher than NaCl, dissolved CO2 content also varies. The homogenization temperature (Th) of the two-phase inclusions ranged from 164 ℃ to 217 ℃, and the homogenization temperature range of the salt-bearing salt-bearing brine inclusions ranged from 217 ℃ to 344 ℃. CO2-rich inclusions (salinity equivalent to 1-22 wt% NaCl, CO2 density 0.28-0.77 g · cm-3, and homogenization temperature 289-344 ° C) are secondary to magnesite, but this The inclusions are dominant in quartz associated with ores, and are associated with stone-containing salts