GEOLOGIC FACTORS CONTROLLING MINERAL CONTENT IN SELECTED TERTIARY COALS - SOUTHERN KALIMANTAN
DOI:
https://doi.org/10.30556/imj.Vol12.No2.2009.565Keywords:
syngenetic and epigenetic minerals, geologic factors, maceral, Asem-Asem coalAbstract
Geologic aspects, particularly geologic history and depositional environment, have a main role in the distri- bution of mineral matter in association with maceral composition in coal. The Asem-Asem coals include Miocene and Eocene coals, which are associated with clay minerals, quartz, pyrite and carbonate. The average mean mineral content of the Miocene coals (3.9%) is lower than that of the Eocene coals (6.7%). This indicates that the lower content reflects the balance of the subsidence rate and the peat accumulation rate during the Miocene was absolutely different from those during the Eocene. Consequently, this influ- enced the mineral input to the respective peats. The lower mineral content of the Miocene coals is associated with the bright lithotypes or the vitrinite-rich coals. Otherwise, the higher one of the Eocene coals is associ- ated with dull lithotypes or the vitrinite-poor coals.
Methods applied in this study include optical microscopy (reflected-white light and fluorescence mode), X- ray diffraction and scanning electron microscopy (SEM).
Clay minerals dominated by kaolinite were deposited in a fresh water environment during peat formation. Most of the minerals are syngenetic in origin. However, some of them are considered to be epigenetic (these clays are in fissures). Quartz is mostly syngenetic, although epigenetic quartz is present. Pyrite takes place as grains and a replacement mineral in organic matter. Calcite is mostly epigenetic occurring in fractures and fissures.
References
Clymo, R.S., 1987. Rainwater-fed peat as a pre- cursor of coal. In: Scott, A.C. (ed.), Coal and coal bearing strata: recent advances. Geologi- cal Society of London, Special Publication, 32, pp. 171-185.
Darman, H. and Sidi, F.H., 2000. An outline of the geology of Indonesia, Indonesian Association of Geologists, Jakarta, 192 p.
Davis, R.C., Noon, S.W. and Harrington, J., 2007. The petroleum potential of Tertiary coals from Western Indonesia: relationship to mire type and sequence stratigraphic setting. Interna- tional Journal of Coal Geology, vol.70, issues 1-3, p. 35-52.
Katili, J.A., 1989. Evolution of the Southeast Asian arc complex. Geology of Indonesia, 12, p. 113- 143.
Koesoemadinata, R.P., Hardjono, Usna, I. and Sumadirdja, H., 1978. Tertiary coal basins of Indonesia. CCOP Technical Bulletin 12, p. 45- 86.
Lyons, P.C., Whelan, J.F. and Dulong, F.T., 1989. Marine origin of pyritic sulphur in the Lower Bakerstown coal bed, Castleman Coalfield, Maryland (USA). International Journal of Coal Geology, 12, p. 329-348.
Miller, R.N. and Given, P.H., 1978. A geochemi- cal study of the inorganic constituents in some low-rank coals. Coal Research Section, Penn- sylvanian State University, 314 p.
Panggabean, H., 1991. Tertiary source rocks, coals and reservoir potential in the Asem- Asem and Barito Basins, Southeastern Kalimantan, Indonesia. PhD Thesis, the Uni- versity of Wollongong, 224 p. (unpublished).
PT. Arutmin Indonesia, 1986. Geology of block 6 South Kalimantan, Indonesia. PT. Arutmin report, 22 p (unpublished).
Sikumbang, N., 1986. Geology and tectonic of pre- Tertiary rocks in the Meratus Mountains, Southeast Kalimantan, Indonesia. PhD Thesis, the University of London, 400 p (unpublished).
Siregar, M.S. and Sunaryo, R., 1980. Depositional environment and hydrocarbon prospects, Tanjung Formation, Barito Basin, Kalimantan. Proceedings of Indonesian Petroleum Asso- ciation, 9th Annual Convention, Jakarta, p. 379- 400.
Stach, E., Mackowsky, M.-TH., Teichmüller, M., Taylor, G.H., Chandra, D. and Teichmüller, R., 1982. Stach’s textbook of coal petrology. Stuttgart, 535 p.
Witts, D., 2008. Borneo and the evolution of the Makassar Straits: sedimentology, stratigraphy and provenance of the Cenozoic Barito Basin, SE Kalimantan, Borneo. Ph D Project. South- east Asia Research Group.
Downloads
Issue
Section
License
Indonesian Mining Journal provides immediate open access to its content on the principle that making research freely available to the public to supports a greater global exchange of knowledge.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
