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根据１５万区域地质调查，将区内的早前寒武纪基底划分为变质上壳岩、中粗粒黑云长英片麻岩、变黑云母钾长花岗岩和变质基性岩四个岩石单元。通过对上述岩石单元岩石类型、地球化学特征、变质变形作用及同位素年代学研究，对其形成时序进行了讨论，由此确定了本区早前寒武纪基底的地质演化轮廓，即在中晚太古时期，本区经历了由玄武安山岩和英安岩双峰式火山建造为主体的上壳岩系的形成阶段，并于２．６Ｇａ遭受角闪岩相变质；随即伴有大规模的ＴＴＧ深成岩浆活动，晚太古末经历绿帘角闪岩相的区域变质作用；至早元古初期，深熔成因的钾质花岗岩侵位，区内已存的早期变质岩石受到该期钾质岩浆的交代改造，并在其成岩之后遭受绿片岩相的区域变质。
Based on the 150,000 regional geological survey, the Early Precambrian basement in the area is divided into four rock units: metamorphic upper crust, middle-coarse black alluvial gneiss, biotite k-long granite and metamorphic basic rock . Through the study of rock types, geochemical characteristics, metamorphism and deformation of rock units and isotopic chronology, the forming sequence is discussed, and the geological evolution profile of the basement of the former Precambrian basement is determined, that is, During the Archean period, the area underwent the formation of the upper crustal rocks dominated by the basaltic andesite and the dacite volcanic eclogite and suffered amphibolite facies metamorphism at 2.6Ga; accompanied by large-scale TTG deep magma In the early Early Proterozoic, the potash-bearing granitic emplacement of the deep-melting was emplaced. The early metamorphic rocks in the area were metamorphosed by the karst magmatism , And undergo metamorphism of the Greenschist facies after its diagenesis.