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热液对石英的淋滤是结晶岩石中固相线以下常见的蚀变类型之一。它常件随钠和(或)钾的交代作用,从而增强了岩石原始矿物成分的重要蚀变。根据系统的矿物成分和流体包裹体研究,对蚀变作用的物理化学条件进行了估计。H_2O-NaCl体系低盐度的流体,在350±50℃条件下,被圈闭成密度变化很大的液体包裹体。最初相对于石英不饱和性是由成分相似但密度、温度不同的流体混合作用所致。在混合时的温度条件下,石英在中等密度(混合后的密度)中的溶解度高于其在两种初始流体中的溶解度,因而引起了石英的溶解。据获得的微构造标志(微裂隙及与石英溶解作用有关的流体包体的轨迹)和重建的应力场资料的结合,确定了流体迁移的几何学。利用矿物学和流体包体研究所获得的数据建立了地球化学模型。
Leaching of quartz by hydrothermal leaching is one of the common types of alteration below the solidus in crystalline rocks. It is often accompanied by the exchange of sodium and / or potassium, which enhances the important alteration of the original rock mineral composition. Based on the systematic study of mineral composition and fluid inclusions, the physico-chemical conditions of alteration are estimated. H_2O-NaCl system of low salinity fluid, at 350 ± 50 ℃ conditions, was trapped into a very large density of fluid inclusions. Initially with respect to quartz unsaturation is caused by the mixing of fluids of similar composition but different density and temperature. The quartz’s solubility in medium density (mixed density) is higher than its solubility in both initial fluids under mixing temperature conditions, thus causing the dissolution of quartz. The geometry of the fluid migration is determined by the combination of acquired microcosmic markers (microcracks and trajectories of fluid inclusions associated with quartz dissolution) and reconstructed stress field data. Geochemical models were established using data obtained from mineralogy and fluid inclusions studies.