KOMPOSISIS MASERAL DALAM PENENTUAN LINGKUNGAN PENGENDAPAN BATUBARA, LAPANGAN SEMBARATA, BERAU, KALIMANTAN TIMUR

• Main Author: URSULA AIPASSA, VIRONIA
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/69598
• Institution: Institut Teknologi Bandung

Coal seams surrounding research area, Sambarata field, Berau, East Kalimantan in Latih Formation which is one of coal bearing in East Kalimantan. This formation is deposited in the delta plain environment. Tropical climate with high rainfall of this area yielded highmoor peat in a humicacid forming environment that can be reflected by the vary macerals composition and their low content of ash and sulphur. Reconstruction of peat depositional facies is carried out by using three diagrams, which is having relatively different index. These parameters are gelification index (GI), tissue preservation index (TPI), groundwater influences (GWI) and vegetation index (VI). Maceral type variation of the coals were observed by petrographic examination from 28 coal samples. The coals are dominated by maceral group of vitrinite and scattered points in reconstruction diagrams show relatively different results. The first group of coal is deposited in limno-telmatic condition in marsh– fen area, lower delta plain environment. This first group environment characterized by its desmokolinite maceral dominated, which convinced angiosperm tree/small tree originated. The Second group of coal is deposited in telmatic condition in swamp area, upper delta plain environment. This second enviromnent characteristized by its telokolinite maceral dominated, which convinced woody plant originated. The similarities and differences in maceral type characteristics in the coals describe their geological setting when occurred. The differences of coal type reflect climate influence and differences in peat depositional environment.