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层状磁黄铁矿硫化矿石产于加纳查尔比拉,后者形成太古宙科拉尔绿岩带镁铁质火山及火山沉积地体的一部分。该矿石与石墨-石英-绢云母片岩成互层,并且和该地区伴生的岩石类型一起变质和变形。在数量上,矿石矿物以磁黄铁矿为主,其次为黄铜矿、黄铁矿、闪锌矿、方锌矿、磁铁矿和四方硫铁矿。共存硫化物相的矿物化学表明在587℃及4.98千巴总压时平衡。反映在各种硫化物组合中的硫和氧的逸度差别相当大,但其流体成分在变质作用过程中实际上受到内部控制,而不是由外部强加。共存的磁黄铁矿、黄铁矿和磁铁矿表明,在变质作用的顶点,log fs_2=-2.4,log fo_2=-17.8。据认为,该矿石具有火山沉积类型,后来因地壳运动时的活化/再活化而起了变化。这些成矿金属和硫可能来自火山喷气。
Layered pyrrhotite sulphide ore was produced in Chalpela, Ghana, which forms part of the mafic volcanic and volcanic sedimentary bodies of the Archean Corral greenstone. The ore interbedded with the graphite-quartz-sericite schist and metamorphosed and deformed along with the associated rock types in the area. In terms of quantity, the ore minerals are mainly pyrrhotite, followed by chalcopyrite, pyrite, sphalerite, wurtzite, magnetite and tetragonal pyrite. The mineral chemistry of the coexisting sulphide phase shows equilibrium at 587 ° C and 4.98 kbar total pressure. The differences in fugacity of sulfur and oxygen reflected in the various sulphide combinations are substantial, but their fluid composition is actually controlled internally rather than externally by metamorphism. Coexisting pyrrhotite, pyrite and magnetite indicate that at the apex of the metamorphism log fs_2 = -2.4 and log fo_2 = -17.8. It is believed that the ore has a volcanic sedimentary type that later changed due to activation / reactivation during crustal movement. These metallogenic metals and sulfur may come from volcanic jets.