MINERALIZATION PARAGENESIS STUDY OF BATUBESI AREA, WEST BELITUNG DISTRICT, BANGKA BELITUNG PROVINCE

• Main Author: Fakhri Anwar Putra, M.
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/71721
• Institution: Institut Teknologi Bandung

The research area is located in Batubesi area, Burung Mandi urban village, Damar sub-district, West Belitung district. This area is included in IUP PT. TIMAH Tbk. region and is still actively being mined for its tin and iron ore. Skarn deposit is the dominant deposit system that is developing in Batubesi area. So far, no research has been done on mineralization paragenesis study in this area. Therefore, this research intends to learn about mineralization paragenesis to have more detailed knowledge about skarn deposit in Batubesi area. This study aims to determine rock core profile in Batubesi Area, provide an overview about rock core subsurface cross section and determine the mineralization paragenesis phase that is developing in Batubesi area. The data used in this study is primary data that are received from 4 rock core samples that has already in half core form, 20 thin section samples, 7 polished section samples, 234 logging photos and 4 logging descriptions. The methods used in this study research are megascopic petrology analysis and petrography and mineragraphy analysis. Rock core profile in this research area is divided to 4 major zones, namely hematitic claystone zone, skarn zone(which divided more to 3 sub types, banded like texture skarn, magnetite skarn, and garnet skarn), hornfels zone/metamorphic rock zone, and granite intrusion zone. Based on petrography and mineragraphy analysis on rock samples, the mineralization paragenesis that is developing in this area is divided to 4 main phases, the first phase is metamorphic phase that is characterized by muscovite and sericite occurence, the second phase is early alteration phase which is progradation skarn alteration that is characterized by garnet and pyroxen mineral, the next phase is late alteration phase which is retrogradation skarn alteration that is characterized by magnetite, chlorite, quartz and sulfide minerals occurence, and the last phase is supergene and oxidation phase which characterized by goethite, hematite, limonite and jarosite mineral occurence. This phase is a result of strong influence from meteoric water and erosion process.