Numerical Modeling Of A High-Temperature Geothermal System In A Volcanic Complex: Case Study From The Kepahiang Field, Indonesia

Authors

  • Hardy Ferrysian Logiani Geothermal Engineering Master’s Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, Indonesi
  • Sutopo Geothermal Engineering Master’s Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, Indonesi
  • Heru Berian Pratama Geothermal Engineering Master’s Program, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, Indonesia
  • Yodha Yudhistira Nusiaputra PT PLN (Persero), Jalan Trunojoyo Blok M-1 No. 135, Jakarta, Indonesia

Keywords:

numerical simulation, natural state, kepahiang, volsung

Abstract

The Kepahiang Geothermal Working Area, located in Bengkulu Province, Indonesia, is a high-elevation, high-enthalpy geothermal system characterized by fumaroles, solfataras, and steaming grounds around Mount Kaba and Sempiang. This study aims to update the conceptual model using integrated geoscience data and numerical simulation. Three main reservoirs were identified: Kaba (up to 370°C), Sempiang (240–300°C), and Grojogan Sewu (200–250°C), overlain by a cap rock ranging from 500 to 1,500 meters thick. A numerical model using VOLSUNG software was developed, covering the natural-state conditions and calibrated with data from the KPH-01 temperature gradient well (452 m depth) and geothermometer surface manifestations. The model results align well with field observations, indicating upflow zones near Sempiang and lateral outflows toward Grojogan Sewu. However, further validation using deep exploration wells is necessary to confirm reservoir geometry and productivity. The study concludes that Kepahiang hosts a promising liquid-dominated geothermal system with structurally controlled fluid flow. It is recommended to drill at least three exploration wells in key upflow zones, particularly around Sempiang to support production planning

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References

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Published

2025-10-29

How to Cite

Logiani, H. F., Sutopo, S., Pratama, H. B., & Nusiaputra, Y. Y. (2025). Numerical Modeling Of A High-Temperature Geothermal System In A Volcanic Complex: Case Study From The Kepahiang Field, Indonesia. ITB Graduate School Conference, 5(1), 407–421. Retrieved from https://gcs.itb.ac.id/proceeding-igsc/index.php/igsc/article/view/616

Issue

Vol. 5 No. 1 (2025): The 6th IGSC 2025

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Articles

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