Abstract
DOI: 10.17014/ijog.5.3.251-263
Northwest Java Basin is one of the Indonesian basins that has the potential of hydrocarbon reservoir. A petrophysical analysis plays a role in determining the physical properties of reservoir rocks such as shale volume, porosity, and water saturation zones which is to analyze the hydrocarbon zone possibilities (net pay). A qualitative analysis and correlation of rock lithology study were carried out at seven wells, while a quantitative study was performed by calculating the volume of the shale with a linear method, density-neutron porosity, and water saturation using simandoux equation, then zoning the prospect zones was finally done. Based on the calculation and data analysis, Vsh cutoff value obtained is 23%, the porosity is 10.6%, and water saturation is 71%. Then, the zones of hydrocarbon prospects were recovered, that are the PI-08 wells (9.632 ft - 9.662 ft), PI-10 (9.420 ft - 9.468 ft, 9.475 ft - 9.516 ft, 10.155 ft - 10.175 ft), well PI-11 (9.268 ft - 9.288 ft), well PI-11ST (9.268 ft - 9.927 ft), well PI-12 (9.396 ft - 9.461 ft, 10.047 ft - 10.059 ft), and PI-13 wells (9.356 ft - 9.416 ft, 9.980 ft - 10.000 ft).
References
Amril, A., Sukowitono, and Supriyanto, 1991. Jatibarang Subbasin - a half Graben Model in the Onshore of Northwest Java. Proceedings, Indonesian Petroleum Association 20th Annual
Convention, Jakarta, p.279-307.
Arpandi, D. and Patmosukismo, 1975. The Cibulakan Formation as one of the most prospective stratigraphic units in the Northwest
Java basinal area. Proceedings, Indonesian Petroleum Asociation, 4th Annual Convention Indonesia, p.181-210.
Asquith, G. and Gibson, C., 1982. Basic well log analysis for geologist. AAPG Method in Exploration Series. Tulsa, Oklahoma. 103pp.
Harsono, A., 1997. Evaluasi Formasi dan Aplikasi Log, Edisi 8,. Schlumberger oilfied service, Jakarta, Indonesia.
Krygowski, A.D., 2003. Guide to Petrophysical Interpretation. Austin, Texas, USA.
Noble, R.A., Pratomo, K.H., Nugrahanto, K., Ibrahim, A.M., Prasetya, I., Mujahidin, N., Wu, C.H., and Howes, J.V.C., 1997. Petroleum System of Northwest Java Indonesia. Proceedings,
Indonesian Petroleum Asociation, 26th Annual Convention. Jakarta, p.585-600.
Pertamina, 1996. Petroleum Geology of Indonesian Basins; Principles, Methods and Application, Volume III West Java Sea Basins. Indonesia.
Schlumberger, 2009. Schlumberger Log Interpretation Charts. Schlumberger Ltd. New York. p.26-60.