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红湖绿岩带的岩浆演化伴随约2730和2700Ma间周围岩基的侵位,经历了漫长的火山活动时期(约在2992和2733Ma间)。该区的主要金矿床及与之伴生的强蚀变岩石,在空间上与巨大、多相的剪切系(变形带)有关,它在区域范围横切火山岩系。含金侵入体的U—Pb法年龄测定结果表明,这些大型构造制约了变形的主要阶段以及2720Ma以后的金矿化作用,即值得注意的晚于火山活动期。变形带的形成与周围岩基的底辟侵位有关。在该绿岩带东段和中段所进行的详细研究揭示出,与金矿化伴生的强蚀变作用无论是时间上和空间上均与邻近岩基周围发育的接触变质晕有关。沿变形带,蚀变组合记录了环绕围岩中广泛反映接触热变质梯度的热梯度情况。镁铁质火山岩,通过绿片岩相变质作用蚀变为石英、铁白云石、绢云母、绿泥石、方解石组合;而通过角闪岩相变质作用,则蚀变为石英、黑云母、白云母、柘榴石、红柱石、十字石、堇青石、硬绿泥石组合。根据对坎贝尔矿山和迪肯森(现为A.W.怀特)矿山的研究,认为金矿化与热变质作用高峰期是同时的,但接在大多数碳酸盐蚀变之后的却发生在剪切变形史晚期。综合证据表明,伴有金矿化的接触热变质作用、变形作用和强烈蚀变作用是同时代的产物,并直接与岩基侵位作用有关。
The magmatic evolution of the Honghu greenstone belt has experienced a long period of volcanic activity (about 2992 and 2733 Ma) with the emplacement of rock mass around 2730 and 2700 Ma. The major gold deposits in the area and their associated strongly altered rocks are spatially related to the vast and heterogeneous shear zones (deformation zones) that transect volcanic rocks in the area. U-Pb dating of gold-bearing intrusions shows that these large structures constrain the major stages of deformation and gold mineralization after 2720 Ma, which is noteworthy later than volcanic activity. The formation of deformation zone is related to the emplacement of diabase in the surrounding rock foundation. A detailed study conducted in the eastern and middle sections of the Greenstone Belt reveals that the strong alteration associated with gold mineralization is related both to the metamorphic halo developed in the vicinity of the surrounding rock mass temporally and spatially. Along the deformation zone, the combination of alteration records the thermal gradients that widely reflect the thermal metamorphic gradients in the surrounding rocks. The mafic volcanic rocks are altered into quartz, iron dolomite, sericite, chlorite and calcite by green metamorphism facies metamorphism. By amphibolite facies metamorphism, alteration to quartz, biotite and muscovite , Garnet, andalusite, aragonite, cordierite, and chlorite combinations. According to a study of the Campbell and Dickenson (now AW White) mines, the peak of gold mineralization and thermal metamorphism is considered to be simultaneous, but most of the carbonate alteration occurs after shear deformation Late history The comprehensive evidence shows that the contact thermal metamorphism accompanied by gold mineralization, deformation and intense alteration are the products of the same age and are directly related to the emplacement of the rock mass.