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就剪切带金矿床的成矿热液流体的组成、稳定同位素和微量元素特征而言,很难对成矿流体的来源下明确结论。成矿流体有四种可能来源:变质的、岩浆的、地幔排气的、下地壳麻粒岩化和深循环地下水的来源。前三种来源有地球化学证据,因而不能完全排除其可能性。第四种来源因为它与剪切带流体为低盐度、高压力这一特征相矛盾而尚未被大多数科学工作者所接受。同一矿床或同一地区的成矿流体的同位素均一化提供的证据说明均一化发生在成矿流体进入剪切带之前,也就是说,在剪切带之下存在均一的流体带。与剪切带动力作用最密切相关的成矿流体的物理化学参数是温度、压力和相态。流体相分离是剪切带成矿流体的普遍特征,它能反映剪切带对金矿化的控制。流体是剪切带活动性和成矿作用的介质,流体地球化学特征的研究是对成矿流体和成矿元素的来源有较好认识的重要途径之一。在研究剪切带和成矿之间的联系中认识成矿物质来源是非常重要的。如果没有成矿物质来源,甚至在最有利的构造环境,如流体活动和矿质沉淀的化学环境,也不会发生成矿作用。剪切带流体记录有两种方式:一是由流体与围岩间相互反应形成的蚀变矿物组合;另一是蚀变矿物和脉石矿物中的流体包裹体。它们是剪切带流体的地球化学特征研究的主
With regard to the composition, stable isotopes and trace element characteristics of hydrothermal fluids in the shear zone gold deposits, it is difficult to draw a clear conclusion on the origin of the ore-forming fluid. There are four possible sources of ore-forming fluids: metamorphic, magmatic, mantle-derived, lower crustal granulomatization and the source of deep-cycle groundwater. The first three sources have geochemical evidence and can not completely rule out their possibility. The fourth source has not been accepted by most scientific workers because it contradicts the feature of low salinity and high pressure in shear zone fluids. The evidence provided by the isotopic homogenization of the ore-forming fluid in the same deposit or area shows that homogenization occurs before the ore-forming fluids enter the shear zone, that is, there is a uniform fluid zone beneath the shear zone. The physicochemical parameters of the ore-forming fluids that are most closely related to the shear-band motions are temperature, pressure and phase. Fluid-phase separation is a common feature of shear-zone ore-forming fluids and reflects the control of gold mineralization by shear zones. Fluid is the medium of shear zone activity and mineralization. The study of fluid geochemical characteristics is one of the important ways to understand the source of ore-forming fluid and metallogenic element. It is very important to know the source of metallogenic material in the study of the relationship between shear zone and mineralization. Without mineralization sources, mineralization does not occur even in the most favorable tectonic setting, such as chemical activity of fluid activities and mineral deposits. There are two ways to record fluid in shear zone: one is the alteration mineral assemblage formed by the mutual reaction between fluid and surrounding rock; the other is fluid inclusions in altered minerals and gangue minerals. They are the study of geochemical characteristics of shear zone fluids