Characteristics of the Triassic Source Rocks of the Aitutu Formation in the (West) Timor Basin

Asep Kurnia Permana, Aries Kusworo, Andi Heri Prastian

Abstract


DOI:10.17014/ijog.v1i3.192

The Triassic rocks of the (West) Timor Basin have been identified that was mainly deposited in the  marine environment. The fine grained clastics and carbonate  rocks of this Triassic marine  facies are considered to be the most promising source rocks potential in this basin. In this paper we present geochemical and petrographic data from outcrop samples of the Triassic carbonate Aitutu Formation, due to emphasized the organic maturation, kerogen type of the organic matter and the origin of the organic matter.  A representative of selected sample were subjected to the Rock-Eval Pyrolisis, vitrinite reflectance and thermal alteration index, bitumen extraction, were analyzed on the GC-MS. The samples were collected from marine deposit of the Triassic Sequence. The TOC values of the analyzed sample range between rich and rich organic richness (0.51% - 9.16%, wt.%, TOC), which consists mainly of type II and III kerogen and the organic matter consider to be predominantly oil/gas prone and gas prone potential. The thermal maturity assessed from Tmax, TAI, and vitrinite reflectance shows an immature to early peak mature stage of the organic matter. The GC-MS analyses of the biomarkers indicate mainly the organic matter derived from mixed source rocks facies containing alga debris and higher plant terrestrial origin.


Keywords


source rock potential; Triassic Aitutu Formation; (West) Timor Basin

References


Audley-Charles, M.G. 1968. The Geology of Portugese Timor. Memoirs of the Geological Society of London, 54, 76pp.

Audley-Charles , M.G. and Carter, D.J., 1972. Paleogeographical significance of some aspects of Paleogene and Early Neogene Stratigraphy and tectonics of the Timor Sea region. Paleogeography, Paleoclimatology, Paleoecology, 11, p.247-264.

Bird, P.R., 1987. The geology of the Permo-Triassic Rocks of Kekneno, West Timor. Unpublished Phd Thesis. University of London, 368pp.

Charlton, T.R., 2001. The petroleum potential of West Timor. Proceedings, Indonesian Petroleum Association, 28th Annual Convention and Exhibition, 1, p.301-317.

Charlton, T.R., 2002. The petroleum potential of East Timor. APEA Journal, p.351-369.

Cook, S.E., 1986. Triassic sediments of East Kekneno, West Timor. Unpublished Ph.D thesis. University of London, 384pp.

Kraus G.P. and Parker K.A., 1979. Geochemical evaluation of petroleum source rock in Bonaparte Gulf-Timor Sea region, Northwestern Australia. American Association of Petroleum Geologists Bulletin, 63 (11), p.2021-2041.

Permana, A.K., 2012. Laporan Akhir Penelitian Stratigrafi Cekungan Timor. Pusat Survei Geologi-Bandung, 123pp. (Unpublished).

Pedersen, T.F. and Calvert, S.E., 1990. Anoxia vs. Productivity : what control the formation of organic carbon rich sediment and sedimentary rocks. American Association of Petroleum Geologists Bulletin, 74 (4), p.454-466.

Peters, K.E., Fraser, T.H., Amris, W., Rustanto, B., and Hermanto, E., 1999. Geochemistry of crude oils from Eastern Indonesia. American Association of Petroleum Geologists Bulletin, 83, p.1927-1942.

Price, P.L., O’Sullivan, T., and Alexander, R., 1987. The nature and occurrence of oil in Seram, Indonesia. Proceedings, Indonesian Petroleum Association, 16th Annual Convention and Exhibition, p.141-173.

Waples, D.W. and Machihara, 1991. Biomarker for Geologist-A Practical Guide to the Application of Steranes and Triterpanes in Petroleum Geology. American Association of Petroleum Geologists. Methods in Exploration Series, 9, 91pp.

Wilson, J.L., 1975. Carbonate facies in geological hystory, New York, Springer-Verlag. 471pp.


Full Text: PDF

Refbacks

  • There are currently no refbacks.


Creative Commons License
Indonesian Journal on Geoscience by https://ijog.geologi.esdm.go.id/index.php/IJOG/index is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.

 

Indexing Site :

Follow us on:


shopify visitor statistics
View My Stats