The Occurrence and Genesis of Silicified Coals in Tanjung Redeb, Embalut, and Loa Kulu, East Kalimantan, Indonesia

Autor: Mulyono Dwiantoro, Teti Indriati, Agus Haris Widayat, Mirza Dian Rifaldi, Miqdam Furqany, Komang Anggayana, Andy Yahya Al Hakim
Rok vydání: 2021
Předmět:
Zdroj: Indonesian Journal on Geoscience. 9
ISSN: 2355-9306
2355-9314
DOI: 10.17014/ijog.9.1.27-43
Popis: The occurrence and genesis of silicified coals in Tanjung Redeb, Embalut, and Loa Kulu have been described and reconstructed by means of petrography and geochemistry. The silicified coals are black, hard, and contain dispersed fine-grained silica minerals. Silica (SiO 2 ) contents vary from 58 to 76%, and LOI (mostly represents organic matter) ranges from 23 to 40% of the bulk silicified coal samples based on the ICP-INAA analysis. Microscopic examination shows the presence of quartz, chalcedony, and amorphous opal. Silicification occurs both as layers and nodules within the coal seams. The layer type is usually thin layers (
Databáze: OpenAIRE