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对浙江省内花岗质岩石样品薄片在偏光显微镜下鉴定,试图建立矿物学与微构造之间的联系,确定裂隙分布矿物学控制因素,并调查微裂隙与交代变质蚀变之间的关系.薄片显示花岗质岩石主要由斜长石、钾长石、石英和云母组成.其中长石和云母解理发育,在结构上更易于变形,而石英则表现为均质特征,其中的裂隙比其他矿物(长石、云母)中更发育.这些解理和裂隙接纳流体进入并造成交代变质.在此过程中,黑云母被白云母交代而形成石英并释放出钾,这些钾进而交代斜长石而形成钾长石.值得关注的是,一些矿物颗粒边界显现出很少的变形,如钾长石-斜长石边界和石英-石英边界呈现较低程度的颗粒间碎裂,并变得可能比以前更坚硬,这是因为重结晶作用和交代作用胶结了以前的碎裂结构.最后,变形作用影响到整个岩石,为流体通过岩石打开通道,进一步的微裂隙对大规模钾交代变质作用的发生至关重要.研究区内花岗岩的矿物学及裂隙特征表明,交代作用可以作为可靠的构造标志,用以恢复浙江花岗岩现代和古裂隙的几何特征.
The sample of granitic rocks in Zhejiang Province was identified under a polarizing microscope in an attempt to establish the relationship between mineralogy and microfacies, determine the mineralogical control factors of fracture distribution and investigate the relationship between microfacies and alteration metamorphism. The flakes show that the granitic rocks are mainly composed of plagioclase, potassium feldspar, quartz and mica, of which feldspar and mica are cleverly developed and structurally more susceptible to deformation, whereas quartz is characterized by homogenization with fissures therein The minerals (feldspar, mica) are more developed, and these cleavages and fissures admit fluids and cause metamorphism, during which the biotite is replaced by muscovite to form quartz and release potassium, which in turn concretes plagioclase It is noteworthy that some of the mineral grain boundaries show little deformation and it is possible that the feldspar-plagioclase boundary and the quartz-quartz boundary exhibit a lower degree of intergranular fragmentation Harder than before, because the recrystallization and metasogenesis cemented the previous fragmented structure. Finally, the deformation affected the entire rock, opening the passage for fluid through the rock, with further micro-cracks on the large Scale K metasomatic metamorphism is of crucial importance.The mineralogical and fracture characteristics of granites in the study area indicate that the metasomatism can be used as a reliable tectonic marker to restore the geometric characteristics of the modern and ancient fractures of Zhejiang granite.