GEOLOGY, ALTERATION AND MINERALIZATION IN THE PANGULIR AREA, SUMBAWA DISTRICT, WEST NUSA TENGGARA PROVINCE

• Main Author: Yulanda, Maspamil
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/80342
• Institution: Institut Teknologi Bandung

The research area is administratively located in Pangulir, Ropang District, Sumbawa Regency, West Nusa Tenggara Province. The coordinates of the study area is at 557569- 558708 mE and 9008857-9010736 mN zone 50S datum WGS 1984, with a study area of approximately 2,095 m2. Pangulir area is a concession area owned by PT Sumbawa Jutaraya as a greenfield prospect that is being explored. The Pangulir area has relatively complex geological conditions and is patterned with NW-SE and NE-SW structures originating from N-S trending subduction that undergoes compression. In general, there are four main rock units found in the study area, consist of andesite lava, tuff, diorite, and microdiorite. Alteration zones found in the study area are propylitic zone (chlorite + illite - smectite + calcite + pyrite), argillic zone (kaolinite + illite - smectite + quartz + pyrite), argillic intermediate zone (illite - smectite + chlorite + kaolinite + pyrite), and silicification zone. Metallic minerals found in the study area are pyrite, arsenopyrite, chalcopyrite, sphalerite, galena, and covellite. The presence of gold (Au) and silver (Ag) minerals associated with the occurrence of basemetal sulfide minerals such as chalcopyrite, sphalerite, galena, arsenopyrite, and black sulfide minerals as well as the presence of calcite/carbonate veinlets and crustiform - colloform textures and high base metal content indicate the presence of intermediate sulfidation epithermal deposits in the study area..