KARAKTERISTIK TEKSTUR ENDAPAN EMAS SULFIDASI RENDAH SEBAGAI PENENTUAN ZONA BOILING DAN MINERALISASI PADA ENDAPAN EMAS DAERAH POBOYA, KOTA PALU, PROVINSI SULAWESI TENGAH

Poboya is one of the prospects for low sulfidation epithermal mineralization containing precious metals in Central Sulawesi that the mineralization formation process is controlled by the Palu-Koro sinistral strike-slip fault. The results of the structural activity that occurs in the form of fractures become a transport medium for hydrothermal fluids carrying ore minerals in veins with various textures which can describe the conditions for the formation of low sulfidation epithermal deposits that occur. The diversity of ore and vein mineral textures is an attraction for conducting research in this area. This research is to determine the texture characteristics of low sulfidation epithermal deposits and determine the bowling zone and mineralization from the texture of low sulfidation epithermal deposits in the Poboya area. This research uses surface geological mapping methods and drill data with megascopic, petrographic and mineragraphic analysis. Based on the research results, it is known that the vein textures found laterally in the research area are primary textures in the form of massive chalcedonic, Banded Chalcedonic, Crystalline Carbonate (comb) and replacement textures in the form of Lattice Bladed. The vein textures found vertically in drill holes in the research area are primary textures in the form of massive quartz, banded chalcedonic, chalcedonic, colloform, colloform-crustiform, saccharoidal, vuggy and replacement textures in the form of bladed lattice. The ore mineral textures found in the research area from the results of mineragraphic analysis are replacement, disseminated, intergrowth, actual boundary and infilling textures. The vein texture zoning at the research location falls into 2 zones, namely the Chalcedonic Superzone (CH) which is characterized by the dominant presence of chalcedonic texture with a quartz composition and there is a saccharoidal texture with a carbonate composition and the Crustiform - Colloform (CC) zone which is characterized by the presence of colloform and colloform textures. crustiform. The boiling zone was identified at a depth of between 119.25 – 236.50 m below the surface in drill hole C. Mineralization in the research area is generally found along veins, sheeted veins, stockwork and dissemination in source rocks which is dominated by the formation of base metal-bearing ore minerals such as pyrite, chalcopyrite, galena, covellite and sphalerite. Meanwhile, silver and gold are found in small abundance.
Keywords : Low sulfidation epithermal gold deposits, vein texture, ore mineral texture, boiling zone, mineralization, Poboya.