Geology and Alteration of East Pinolosian Area, Bolaang Mongondow, North Sulawesi Province

Bolaang Mongondow is located on the Eastern North arm of Sulawesi. This area a Neogene-aged magmatic arc composed plutonic and volcanic rocks that indicate mineralization-bearing host rocks. The study aimed to determine geological setting alteration based observations geochemical analysis. method used mapping, followed by laboratory studio data lithology this andesite, diorite, pyroclastic breccia units. Two main faults are Northwest-Southeast trending dextral fault Northeast-Southwest sinistral fault, which causes hydrothermal mineral alteration. Mineral in divided into several zones, including Silicification Zone (massive silica + vuggy silica), Advance Argillic (illite alunite dickite halloysite kaolinite), montmorillonite pyrophyllite), Prophyllitic (chlorite montmorillonite). presence assemblages zones shows characteristics High Sulfide Epithermal deposits with highest level 0.47/ppm Zone.