#TITLE_ALTERNATIVE#

• Main Author: (NIM: 12008005) ; (Pembimbing: Dr. Ir. Chalid Idham Abdullah ; Dr. Ir. Bambang Priadi), ARINA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/18058
• Institution: Institut Teknologi Bandung

Study area is located at N 0o 19' - 1o 15' and E 123o 23'- 123o 43'. Administratively, located in Bone Bolango Regency, Gorontalo Province, Indonesia. Study site is one of the copper and gold mining prospect of PT. Gorontalo Minerals. <br /> <br /> <br /> <br /> <br /> This study used data from six cores. Macroscopic observation, microscopic observation which includes petrographic analysis, mineragraphic analysis, and clay minerals analysis using XRD (X-Ray Difraction) and also geochemical assay data observation were done for each core. <br /> <br /> <br /> <br /> <br /> Based on these observations, we got the result that the study area is consisted of three rock units, namely: Volcanic Rock Unit of Bilungala Volcanic Rocks, Diorite Intrusion Unit of Boliohito Diorite, and Quartz Diorite Intrusion Unit of Boliohito Diorite. In the study area there are six alteration zones, those are: Quartz-Chlorite-Sericite-Calcite Zone, Kaolinite-Montmorillonite Zone, Quartz-Chlorite-Actinolite-Biotite Zone, Quartz-Chlorite-Actinolite-Calcite Zone, Massive Silica Zone, and Silica-Iron Oxide Zone. Mineralization process in the study area is consisted of two types, porphyry copper and supergene enrichment types. The mineralization process formed three zones, namely: Oxidation Zone, Chalcocite-Covellite Zone, and Chalcopyrite-Bornite Zone. <br /> <br /> <br /> <br /> <br /> The age of rocks in the study area is estimated Middle Miocene-Late Miocene, the older rock was crystal tuff of Volcanic Rock Unit, then was intruded by diorite of Diorite Intrusion Unit resulting Quartz-Chlorite-Sericite-Calcite and Kaolinite-Montmorillonite alteration. After that, all rock units were intruded by quartz diorite of Quartz Diorite Intrusion Unit that carried Quartz-Chlorite-Actinolite-Biotite and Quartz-Chlorite-Actinolite-Calcite alteration. Massive Silica Zone was formed by another intrusion on the eastern of section#7(48578N). Porphyry copper mineralization occured simultaneously with diorit and quartz diorit intrusions then supergene enrichment process occured with the intensity increasing of weathering and the rise and fall of water table, this process formed Silica-Iron Oxide Zone .