Bulletin of the Geological Society of Malaysia, Volume 77, May 2024, pp. 15 – 26

Unleashing geological sequestration potential of mature oilfield by enforcing 4-dimensional seismic model-based inversion in Widuri Field, Indonesia

Dwandari Ralanarko¹,*, Brimas Aptanindia Pangestu¹, Edy Sunardi², Ildrem Syafri², Billy Gumilar Adhiperdana²

¹ Pertamina Hulu Energi OSES, RDTX Square Jl. Prof. Dr. Satrio No. 164, Setiabudi, South Jakarta 12930, Indonesia

² Faculty of Geological Engineering, Universitas Padjadjaran, Deanery Building Jl. Ir. Soekarno, Km. 21 Jatinangor, West Java 45363, Indonesia

* Corresponding author email address: dwandari.ralanarko@gmail.com

Abstract: Implementing reservoir characterization by undertaking seismic inversion on time-lapse surveys is very effective for observing the distribution and changes in the hydrocarbon reservoir. In mature oilfields, these changes are most likely influenced by the thermodynamic activities including the injection of fluid into the reservoir, which can change the volume, pressure, and composition of the geological formations. Fluid injection (in this case, water injection) into the reservoir is typically used as an oil and gas booster to increase production through EOR (Enhanced Oil Recovery). However, in light of CCUS (Carbon Capture Utilization and Storage) application, injecting CO₂ can be considered as a new EOR strategy development, with the dual objectives of increasing oil and gas production as well as lowering carbon emissions at the same time. The 4-dimensional (4D) seismic data available over Widuri Field covers an area of 125 km², with 884 inlines and 905 crosslines, acquired in 1991 and 2004 over the same area. The inversion algorithm is using seismic deconvolution to generate an acoustic impedance model before developing a geological reservoir model. Reservoir characterization was conducted in this study to obtain detailed information of the reservoir zones by determining the impact of water injection that replaces hydrocarbons. Intervals and areas with an abundance of water can be considered as potential CO₂ sequestration in the future, as a part of the CCUS application. In conclusion, the findings of increasing impedance from inversion data from 1991 to 2004 can indicate the presence of existing porosity and permeability. This evidence could indicate reservoir capability as CO₂ storage.

Keywords: 4D seismic, enhanced oil recovery, geology, inversion, sequestration

References:

Abdullah, A., 2009. 4-D Seismic. Ensiklopedia Seismik Online. http://ensiklopediseismik.blogspot.com/2009/11/4-d-seismic.html. Accessed on 5 August 2023.

Ayeni, G. & Biondi, B., 2012. Time-lapse seismic imaging by linearized joint inversion – A Valhall Field case study. SEG Technical Program Expanded Abstracts, 1-6. https://doi.org/10.1190/segam2012-0903.1.

Chadwick, R.A., 2010. Quantitative analysis of time-lapse seismic monitoring data at the Sleipner CO₂ storage operation. The Leading Edge, 29(2), 170-177. https://doi.org/10.1190/1.3304820.

Daly, M.C., Hooper, B.G.D.& Smith, D.G., 1987. Tertiary Plate Tectonics and Basin Evolution in Indonesia. Proceedings IPA 16^th Ann. Conv., Jakarta, June 1987, p. 399-428.

Hall, R., 1996. Reconstructing Cenozoic SE Asia. In: R. Hall, R. & D.J. Blundell (Eds.), Tectonic Evolution of SE Asia. Geological Society, London, Special Publications, 106, 153–184.

Longley, I.M., 1997. The Tectonostratigraphic Evolution of SE Asia. In: A.J. Fraser, S.J. Matthews, & R.W. Murphy (Eds.), Petroleum Geology of Southeast Asia. Geological Society, London, Special Publications, 126, 311– 339.

Lumley, D., 1996. 4D Seismic Reservoir Monitoring. Course Book.

Pangestu, B.A., 2022. Interpretasi Seismik 4 Dimensi Untuk Memonitor Injeksi CO₂ Pada Projek Carbon Capture and Storage di Lapangan Sleipner, Laut Utara, Norwegia Menggunakan Metode Inversi. Skripsi, Universitas Pertamina, Jakarta.

Ralanarko, D., Wahyuadi, D., Pranowo Nugroho, Wrahaspati Rulandoko, Ildrem Syafri, Abdurrokhim Almabrury, & Andi Agus Nur, 2020. Seismic Expression of Paleogene Talangakar Formation – Asri & Sunda Basins, Java Sea, Indonesia. Berita Sedimentologi, 46(1), 21-43.

Ralanarko, D., Ramadhan, M.I., Fauzielly, L., Winantris, Syafri, I., & Abdurrokhim, 2021. Reconstruction at Transition Zone Talangakar Formation, Asri Basin, Offshore Southeast Sumatra, Indonesia. Journal of Marine Geology, 19(2), 85-94. (In Indonesian).

Sukanto, J., F., Nunuk, Aldrich, J.B., Rinehart, G.P., & Mirchell, J., 1998. Petroleum System of the Asri Basin, Java Sea, Indonesia. Proceeding IPA 26^th Annual Convention, Jakarta, 291-312.

Manuscript received 9 June 2023;
Received in revised form 18 August 2023;
Accepted 14 November 2023
Available online 30 May 2024

https://doi.org/10.7186/bgsm77202403

0126-6187; 2637-109X / Published by the Geological Society of Malaysia.
© 2024 by the Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution (CC-BY) License 4.0.