Modeling and Interpretation of Geothermal System Components Using the Gravity Method at the “X” Geothermal
DOI:
https://doi.org/10.25299/jgeet.2024.9.2.13032Keywords:
Geothermal field "X", gravity method, complete Bouguer anomaly, gravity modeling, geothermal system componentsAbstract
Geothermal field "X" is one of the geothermal fields located in North Sulawesi Province managed by PT Pertamina Geothermal Energy. This research aims to determine the presence of geothermal system components in the subsurface using the gravity method. Gravity method data processing is processed with observational and theoretical corrections to obtain a complete Bouguer anomaly. The complete Bouguer anomaly is separated into regional and residual anomaly using the upward continuation process. The results of modeling and interpretation of residual (shallow) gravity prove the existence of 3 (three) rock layers and their density values, Post Tondano Andesite Unit layer (2,4 g/cm3), Tondano Rhyolite Unit layer (2,5 g/cm3) and Pre Tondano Andesite Unit layer (2,7 g/cm3). The results of modeling and interpretation of regional (deep) gravity evidence the existence of 3 (three) rock layers along with the rock density value, Tondano Rhyolite Unit layer (2,5 g/cm3), Pre Tondano Andesite Unit layer (2,7 g/cm3) and diorite intrusion rock layer (2,9 g/cm3). The geothermal system in the research area is composed of Post Tondano Andesite Unit as overburden rock, Tondano Rhyolite Unit as caprock, Pre Tondano Andesite Unit as reservoir rock and Diorite intrusion rock as heat source.
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References
Alsadi, H.N. & Baban, E.N. (2014). Introduction To Gravity Exploration Method. Sulaimaniyah : First Edition, Kurdistan Region, Iraq.
Brehme, M., Moeck, I., Kamah, Y., Zimmermann, G., & Sauter, M. (2014). A Hydrotectonic Model of A Geothermal Reservoir – A Study In Lahendong, Indonesia, Geothermics, 51 (2014), p. 228–239.
Brehme, M., Deon, F., Haase, C., Wiegand, B., Kamah, Y., Sauter, M. & Regenspurg, S. (2016). Fault controlled geochemical properties in Lahendong geothermal
reservoir Indonesia. Springer-Verlag Berlin Heidelberg, Grundwasser – Zeitschrift der Fachsektion Hydrogeologie (2016) 21:29–41.
Balmino, G. & Bonvalot, S. (2016). Gravity Anomalies. Springer International Publishing Switzerland, E.W. Grafarend (ed.), Encyclopedia of Geodesy.
Dentith, M. & Mudge, S.T. (2014). Geophysics for the Mineral Exploration Geoscientist. Cambridge University Press.
Fanani, A.F., Prabowo, T., Hastriansyah, G., Pasaribu, F. & Silaban, M. (2021). Application of the Flow Production Test to Update Well Production Capacity in Lahendong Geothermal Field. Proceedings World Geothermal Congress, Reykjavik, Iceland, April - October 2021.
Gregg, A., Nordquist, Jorge, A. & Stimac, J. (2010). Precision Gravity Modeling and Interpretation at the Salak Geothermal Field, Indonesia. Proceedings World Geothermal Congress 2010, Bali, Indonesia, 25-29 April 2010.
Hirt, C. (2015). Gravity forward modelling. In: Encyclopaedia of Geodesy (Ed. E. Grafarend).
Ibrahim, M. M., Utami, P., & Raharjo, I. B. (2022). Analisis Struktur Geologi Berdasarkan Data Gravitasi Menggunakan Metode Second Vertical Derivative (SVD) Pada Lapangan Panas Bumi ”X”. Jurnal Geosains dan Remote Sensing (JGRS), Vol 3, No 2 (2022) 52-59.
Kristiawan, Y., Adityarani, M., Prasetyo, F.X.C., Naafiyanto, D.R., Harijoko, A., & Utami, P. (2013). Penerapan Studi Vulkanologi Dalam Penyelidikan Panas Bumi: Studi Kasus Pada Beberapa Lapangan Panas Bumi Di Indonesia, Proceedings, 13th Indonesia International Geothermal Convention & Exhibition 2013, Assembly Hall - Jakarta Convention Center Indonesia, June 12 – 14, 2013.
LaFehr, T.R. (1991). An Exact Solution for the Gravity Curvature (Bullard B) Correction. Geophysics Vol. 56, No. 8, P. 1179-1184.
Lestari, I. dan Sarkowi, M., 2013, Analisis Struktur Patahan Daerah Panasbumi Lahendong - Tompaso Sulawesi Utara Berdasarkan Data Second Vertical Derivative (SVD) Anomali Gayaberat, Seminar Nasional Sains & Teknologi V, Lembaga Penelitian Universitas Lampung 19-20 November 2013.
PT. Pertamina Upstream Technology Center (2013). Studi Evolusi Pusat Aliran Panas dan Fluida Magmatik Sistem Panas Bumi Lahendong Untuk Pembuatan Rencana Pengembangan Lapangan. Project Report for Pertamina Upsteam Technology Center, UGM Faculty of Engineering. Contract No. 47/D30140/2013-SO, (Unpublished).
Sumintadireja, P., Ushijima K., & Sudarman, S. (2000). Misealamasse and Gravity Data Surveys at The Kamojang Geothermal Field. Proceeding World Geothermal Congress 2000, Japan. P 1784.
Sarkowi, M. (2014). Gravity Exploration. Yogyakarta, Indonesia: Graha Ilmu.
Sidqi, M. & Utami, P. (2018). The Geology and Geothermal Systems of The Minahasa District, North Sulawesi,
Proceedings, The 6th Indonesia International Geothermal Convention & Exhibition (IIGCE) 2018, Cendrawasih Hall - Jakarta Convention Center Indonesia, September 5th - 8th, 2018.
Telford, W.M., Geldart, L.P. & Sheriff, R.E. (1990). Applied Geophysics, Second Edition edn, Vol., pp. Pages, Cambridge University Press, Cambridge.
Utami, P. (2011). Hydrothermal Alteration and The Evolution of The Lahendong Geothermal System, North Sulawesi, Indonesia. A thesis submitted in fulfillment of the requirements for the degree of Doctor of Philosophy in Geology, The University of Auckland.
Utami, P., Widarto, D.S., Atmojo, J.P. Kamah, Y., Browne, P.R.L., Warmada, I. W., Bignall, G. & Chambefort, I. (2015). Hydrothermal Alteration and Evolution of the Lahendong Geothermal System, North Sulawesi. Proceedings World Geothermal Congress, Melbourne, Australia.
Utami, P., Sidqi, M., Siahaan, Y., Shalihin, M.G.J., Siahaan, E.E. & Silaban, M. (2021). Geothermal Prospects in Lahendong Geothermal Field of the Tomohon – Minahasa Volcanic Terrain (TMVT), North Sulawesi, Indonesia. Proceedings World Geothermal Congress, Reykjavik, Iceland, April - October 2021.
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