Claim Missing Document
Check
Articles

Found 3 Documents
Search

DELINEATING RESISTIVITY VALUES OF POTENTIAL GEOTHERMAL AREAS ALONG THE BOGOR FAULT USING 2D MAGNETOTELLURIC INVERSION Hardiansa, Debi; Farid, M; Hadi, Arif Ismul; Al-Ansory, Andre Rahmat; Raihana, Hana; Rahmawati, Nurul 'Ilmi
Indonesian Physical Review Vol. 8 No. 2 (2025)
Publisher : Universitas Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/ipr.v8i2.431

Abstract

Kepahiang Regency, located in an active fault zone, has great geothermal potential with an estimated capacity of up to 154 MW(e), making it a strategic renewable energy source to be developed. This research discusses the geothermal potential in the Kabawetan area, Kepahiang, Bengkulu. The main objective of this research is to evaluate the potential of geothermal resources around the Bogor segment by analyzing the subsurface structure using the Magnetotelluric inversion method and 2D resistivity modeling, in order to identify prospective geothermal reservoir zones. It can evaluate the potential of geothermal reservoirs in Kepahiang. The method used is the Magnetotelluric method, which utilizes the Earth's natural electromagnetic field to determine the distribution of resistivity in the subsurface. The results of 2D modeling with the MT method show potential zones associated with variations in subsurface thermal conditions and the presence of conductive clay minerals with resistivity values between 0.14-1 Ωm. These minerals are thought to be associated with the overburden (reservoir) of the geothermal system that has a depth of 2-4 km. The subsurface layer containing hot water and steam originating from heat emitted from the earth's core with a resistivity value of 2.5-45 Ωm at a depth of 1-4 km is thought to be caprock in the geothermal system, a resistivity value of 120-800 Ωm is thought to be hot rock with a depth between 1.5-10 km. It is estimated that there is a type of andesite rock that has been fractured as a reservoir of geothermal fluid. The findings of this research are expected to contribute to renewable energy as an alternative energy in the future, not only for energy needs but also for regional economic development through tourism and to support sustainable governance.
Analysis of Earthquake Risk Estimation for Sustainable Development Using Microtremor Data Based on Vs30 Distribution: Comparative Study of DFA and Geopsy in Central Bengkulu, Indonesia Arya Putra Anggi; Refrizon, Refrizon; Harlianto, Budi; Apriyanti, Nurul; Saputri, Winda; Febriansyah, Gian Ori; Al-Ansory, Andre Rahmat; Raihana, Hana; Daniel, Adrian; Gumanty, Usman
Jurnal Ilmu Fisika Vol 17 No 2 (2025): September 2025
Publisher : Jurusan Fisika FMIPA Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jif.17.2.214-228.2025

Abstract

This research was conducted in Pondok Kelapa Subdistrict, Central Bengkulu Regency, to analyze subsurface characteristics using microtremor data and the Horizontal-to-Vertical Spectral Ratio (HVSR) method. The research compared DFA (Diffuse Field Assumption) and Geopsy approach. In this study, 40 points were measured with a distance between points ranging from 200 to 300 meters. The data were processed using Terraware-HV and Geopsy software with a Monte Carlo approach to model the 3D subsurface structure. Results show that the dominant frequencies range from 0.64 to 8.19 Hz, with high amplification zones between 1.92 and 7.72 concentrated in areas of loose soil, indicating their high seismic susceptibility. Vs30 values range from 55 to 465 m/s, reflecting the dominance of soft to medium materials, such as clay, gravel, sand, and soft rock at specific depths. 3D modeling revealed a heterogeneous distribution of subsurface materials, with high amplification zones requiring special mitigation. This study provides important insights for seismic risk zoning, disaster mitigation, and earthquake-resistant structure design, and supports sustainable development planning in earthquake-prone areas. The results are expected to serve as a reference in spatial management based on earthquake risk mitigation.
Utilization of Satellite Imagery and Integration of the HVSR Inversion Method for Coastline Changes in the Nangai Beach Tourism Area, North Bengkulu Regency Helinnes, Putri; Hadi, Arif Ismul; Farid, Muchammad; Setyowati, Yuni; Hardiansa, Debi; Gumanty, Usman; Raihana, Hana; Al-Ansory, Andre Rahmat; Muammar, Zaky
Buletin Oseanografi Marina Vol 14, No 3 (2025): Buletin Oseanografi Marina
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/buloma.v14i3.68258

Abstract

This research analyzes shoreline changes in the Nangai Beach area; North Bengkulu Regency using Satellite Image data and analyzes subsurface structures using the Horizontal to Vertical Spectral Ratio (HVSR) method. The main objective of this research is to identify shoreline changes along the Nangai Beach area that occur due to abrasion. Data were collected from 30 points, with a distance of ±100 meters between each point. The research shows that the condition of the area is quite stable to vulnerable to the occurrence of abrasion disasters. Coastline changes were obtained using Satellite Image data from 2011 to 2023. Changes can be observed between points 17 and 35.63 meters, and at point 2, 33.87 meters. The Horizontal-to-Vertical Spectral Ratio (HVSR) method determines dominant frequency values and processes them through amplification to calculate the seismic vulnerability index, sediment layer thickness, and shear wave speed. These values are used to identify areas vulnerable to coastal abrasion. Based on the interpretation, hard rock is shown with a dominant frequency value () in the range 2.35-5.08 Hz, while soft rock is shown in the range 5.71-9.05 Hz. The earthquake vulnerability value () in the range 0.49-2.68 is soft rock, while the value range 3.42-5.61 is hard rock. The lower the vulnerability value (), the more susceptible the area is to abrasion. The shear wave velocity () value is low with a range of 186.83-350.85 while the high value is with a range of 350.85-596.87. A layer of rock with a 3D cross-section can be viewed using 3D modeling software by entering the value of Vs. This research makes a significant contribution to abrasion disaster mitigation through a geophysical approach.