ANALYSIS OF THREE-COMPONENT WAVEFORM INVERSION TO DETERMINE THE FAULT PLANE PATTERNS OF EARTHQUAKES IN THE WEST NUSA TENGGARA REGIONANALYSIS OF THREE-COMPONENT WAVEFORM INVERSION TO DETERMINE THE FAULT PLANE PATTERNS OF EARTHQUAKES IN THE WEST NUSA TENGGARA REGION Muhlis 1, Sukir Maryanto 2, Adi Susilo 2, Didik R Santosa 2, Rais Akbar Alim 3
1. Physics, Faculty Sains, Technology and Matematic, Brawijaya University of Malang, MAN Panggul
2. Physics, Faculty Sains, Technology and Matematic, Brawijaya University of Malang
3. Physics, Faculty Matematics and Natural Sains, Institut Technology of Bandung
Abstract
Sumbawa Island is an earthquake-prone area. Over the past seventeen years, from 2009 to 2025, IRIS has recorded around 350 major earthquakes in Indonesia, 35 of which occurred on the island of Java. For example, on 8 November 2029, at 22:41:05 WIB, an earthquake with a magnitude of Mw = 5.9 occurred. This is because Sumbawa Island is situated between three subduction zones that can trigger earthquakes in Indonesia.
Seismogram analysis using three-component waveforms was conducted to obtain the moment tensor and determine the pattern of subduction fault planes on the island of Java. This research began with a request for several earthquake events from IRIS. Subsequently, using the ISOLA software, data conversion and pre-processing were carried out- the data input included: a crustal model, event information, station selection, raw data preparation, and the definition of the seismic source, calculation of the Green^s function, inversion, and plotting of the inversion results. Subsequently, the fault planes responsible for the earthquakes were depicted using hcplot software. The results of this seismogram analysis revealed that the fault plane patterns developing on the island of Sumbawa consist of normal faults and reverse faults parallel to the islands arc.
Keywords: Three-component waveform inversion, moment tensor, earthquakes
