STUDI ALTERASI DAN PENENTUAN ZONA ALIRAN FLUIDA HIDROTERMAL BERDASARKAN KRISTALINITAS ILLIT DAERAH CIBITUNG, KABUPATEN PANDEGLANG, BANTEN

• Main Author: AQNI SINDU BRAMASTHA, YUNAV
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/36756
• Institution: Institut Teknologi Bandung

The research area is under PT. Aneka Tambang dan PT. Cibaliung Sumberdaya, located in District of Cibitung, Pandeglang Regency, Banten with area 11.24 km2 (coordinates 9248750 – 9252800 mU, dan 571200 – 574200 mT) universal Transverse Mercator (UTM) projection. The study aims to determine the geological conditions, type and distribution of alteration and mineralization, and determine the zone of hydrothermal fluid flow. The method is literature study, mapping and observation, petrography and mineragraphy analysis, kinematic and dynamic analysis, and interpretation of spectral data and illite crystallinity. The research area is characterized by hills and valley of volcanic products and karst plains with mature geomorphic stages. The units of rock in research area can be divided into four units there are Lapilli-Tuff Unit, Andesite-Tuff Unit, Claystone Unit and Calcarenite Unit. The geological structure observed are sheeting joints and faults with NW-SE direction they are Kiarapayung Fault, Citeluk Fault and Cibarengkok Fault. The alteration zones in research area Alunite-Kaolinite-Quartz Zone, Quartz- Dickite-Kaolinite Zone, Illite-Smectite-Pyrite Zone, and Montmorillonite-Calcite- Chlorite Zone. Quartz vein show massive texture, crudely banded colloformcrustiform, and lattice bladed with pyrite and hematite minerals indicating epitermal low sulphidation system. Vectoring zone of hydrothermal fluid flow based on the illite crystallinity shows high value zones in the Kiarapayung area and has a NWSE trend. The alteration zone in the Kiarapayung area is the Alunit-Kaolinite- Quartz zone which is intepreted as zone of the hydrothermal fluid flow. Based on the type of alteration and the texture and presence of pyrite and hematite on quartz veins that refer to the Buchanan model it is interpreted that there is still hope of mineralization potential zone below the surface around the open zone in Kiarapayung.