Keywords
basement fractured reservoir
Discrete Fracture Network
3D Geocellular Modeling
How to Cite
Abstract
DOI: 10.17014/ijog.4.3.121-141
A detailed geological mapping and fracture characterization had been performed in Bantimala area, South Sulawesi, Indonesia. The geology of the studied area is composed of pre-Tertiary metamorphic, sedimentary, and igneous rocks which tectonically mixed forming a mélange complex. Located on the southeastern margin of Sundaland, the tectonic strongly influences the fracture occurrences in the studied area. A total of 3,841 fractures comprising shear fractures, extension fractures, veins, and joints have been measured and analyzed. The common fracture orientations are NW - SE, W - E, NNE - SSW, and ENE - WSW trends. Fractures developing in Bantimala have clearly been controlled by lithology and structure position (i.e. fault zones and fold hinge). The orientation of fractures in Bantimala area is different on each lithology, showing that the fracture system was complex. Fracture intensity in schist is higher compared to the other lithologies. The 3D fracture modeling through 3D geocellular modeling was generated using the result from field data measurements and analyses. Discrete Fracture Network (DFN) was built by fifty-one fracture sets that were analyzed from field measurement data. However, the estimation of average fracture porosity from modeling varies significantly depending on lithology. The value of fracture porosity is relatively small, varied from 0.0004 to 0.0029 %. A high fracture porosity number is observed in an area with a significant fracture intensity and most crosscutting of fracture which in turn is controlled by faults and lithology. A mélange complex can have high potential as a basement fractured reservoir target, where fracture distributions and their attributes will vary depending on the lithology as well as local deformation.
References
Allmendinger, R.W., Cardozo, N., and Fisher, D.M., 2012. Structural Geology Algorithms: Vectors and Tensors. Cambridge, England, Cambridge University Press, 289pp. DOI:10.1017/CBO9780511920202
Bergman, S.C., Coffield, D.Q., Talbot, J.P., and Garrard, R.A., 1996. Tertiary Tectonic and magmatic evolution of western Sulawesi and the Makassar Strait, Indonesia: evidence for a Miocene continent-continent collision. In: Hall, R. and Blundell, D. (eds.), Tectonic Evolution of Southeast Asia, Geological Society Special Publication No. 106, p.391-430. DOI:10.1144/GSL.SP.1996.106.01.25
Berry, R.F. and Grady, A.E., 1987. Mesoscopic structures produced by Plio-Pleistocene wrench faulting in South Sulawesi, Indonesia. Journal of Structural Geology, 9, p.563-571. DOI:10.1016/0191-8141(87)90141-6
Coffield, D.Q., Guritno, N., Wilson, M.E.J., and Ascaria, N.A., 1997. Petroleum Systems of South Sulawesi, Indonesia. In: Howes, J.V.C. and Noble, R.A. (eds.), Proceedings of the Conference on Petroleum Systems of SE Asia and Australasia, p.1001-1010.
Dershowitz, W., Klise, K., Fox, A., Takeuchi, S., and Uchida, M., 2002. Channel Network and Discrete Fracture Network Modeling of Hydraulic Interference and Tracer Experiments and the Prediction of Phase C Experiments. SKB Report IPR-02 - 29. Stockholm, SKB.
Fisher, N.I., Lewis, T., and Embleton, B.J.J., 1987. Statistical Analysis of Spherical Data. Cambridge University Press, 329pp. DOI:10.1017/CBO9780511623059
Fossen, H., 2010. Structural Geology. Cambridge University Press, 463pp. DOI:10.1017/CBO9780511777806
Garrard, R.A., Supandjono, J.B., and Surono, 1988. The Geology of The Banggai-Sula Microcontinent, Eastern Indonesia. Proceedings, Indonesian Petroleum Association, 17th Annual Convention, p.23-52.
Hall, R. and Smyth, H.R., 2008. Cenozoic arc processes in Indonesia: identification of the key influences on the stratigraphic record in active volcanic arcs. In: Draut, A.E., Clift, P.D., and Scholl, D.W. (eds.), Lessons from the Stratigraphic Record in Arc Collision Zones, The Geological Society of America Special Paper 436. DOI:10.1130/2008.2436(03)
Hasan, K., 1991. The Upper Cretaceous Flysch Succession of the Balangbaru Formation, Southwest Sulawesi. Proceedings, Indonesian Petroleum Association, 20th Annual Convention, p.183-208.
Koestler, A.G., Milnes, A.G., and Keller, P., 1995. Quantification of fault/fracture systems and their flow behaviour - Based on field analogues. GEO-RECON A.S. Report No. 9501.168, Munkedamsveien 59, 0270 Oslo, Norway.
Koning, T. and Darmono, F.X. , 1989. The geology of the Beruk Northeast Field, Central Sumatra-oil production from pre-Tertiary basement rocks. Proceedings, Indonesian Petroleum Association, 13th Annual Convention, p.385-406.
Koning, T., 1985. Petroleum Geology of the Ombilin Intermontane Basin, West Sumatra. Proceedings, Indonesian Petroleum Association, 14th Annual Convention, p.117-137.
Nelson, R.A., 2001. Geologic Analysis of Naturally Fractured Reservoirs. Gulf Publishing Company, Houston, Texas, 352pp.
Oda, M., 1985. Permeability tensor for discontinuous rock masses. Géotechnique, 35 (4), p.483-495. DOI:10.1680/geot.1985.35.4.483
Sapiie, B., Purwaman, I., Burhan, N., Lanin, E.S., Toreno, E.Y., Apriansyah, D., and Iskandar, O., 2014. An Outcrops Analogue to Basement Fractured Reservoir of Suban Gas Field, South Sumatra Basin, Indonesia. Geological Society of America, Annual Meeting, British Columbia.
Sribudiyani, Muchsin, N., Ryacudu, R., Kunto, T., Astono, P., Prasetya, I., Sapiie, B., Asikin, S., Harsolumakso, A.H., Yulianto, I., 2003. The collision of the East Java microplate and its implication for hydrocarbon occurrences in the East Java Basin. Indonesian Petroleum Association, 29th Annual Convention, IPA03-G-085, 12pp.
Sukamto, R., 1982. Geologi Lembar Pangkajene dan Watampone bagian barat, Sulawesi, skala 1:250.000. Geological Research and Development Centre, Bandung.
Sukamto, R., 1986. Tektonik Sulawesi Selatan dengan Acuan Khusus Ciri-ciri Himpunan Batuan Daerah Bantimala. Doctoral Thesis at Institut Teknologi Bandung, Bandung (unpublished).
Sukamto, R. and Supriatna, 1982. The Geology of Pangkajene and Western part of Watampone, Sulawesi, Geological Map, scale 1:250.000 with explanatory note. Geological Survey of Indonesia in cooperation with USGS.
Sukamto, R. and Westermann, G.E.G., 1993. Indonesia and Papua New Guinea. In: Westermann, G.E.G. (ed.), The Jurassic of the Circum Pacific, Cambridge University Press, p.181-195. DOI:10.1017/CBO9780511529375
Van Leeuwen, T. M., 1981. The geology of Southwest Sulawesi with special reference to the Biru area. In: Barber, A.J. and Wiryosujono, S. (eds.), The Geology and Tectonics of Eastern Indonesia, Geological Research and Development Centre, Special Publication No. 2, p.277-304.
Wakita, K., 2000. Cretaceous accretionary-collision complexes in central Indonesia. Journal of Asian Earth Science, 18, p.739-749. DOI:10.1016/S1367-9120(00)00020-1
Winberg, A., Andersson, P., Byegård, J., Poteri, A., Cvetkovic, V., Dershowitz, W., Doe, T., Hermanson, J., Gomez-Hernandez, J.J., Hautojärvi, A., Billaux, D., Tullborg, E-L., Holton, D., Meier, P., and Medina, A., 2003. Final Report of the TRUE Block Scale Project, Report 4, Synthesis of flow, transport and retention in the block scale. SKB Technical Report TR-02 - 16. Stockholm, SKB.
Yuwono, Y.S., Bellon, H., Maury, R.C., and Soeria-Atmadja, R., 1988. Tertiary and Quaternary geodynamic evolution of South Sulawesi: constraints from the study of volcanic units. Geologi Indonesia, 13, p.32-48.