THE EFFECT OF SEISMIC STATION CONFIGURATION ON THE ESTIMATION OF EARTHQUAKE SOURCE PARAMETERS USING THE THREE-COMPONENT WAVEFORM INVERSION METHOD
Muhlis 1, Sukir Maryanto 2, Didik R Santosa 2, Adi Susilo 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 Unirvesity of Malang
3. Physics, Mathematics and Natural Sciences, Institut Technology of Bandung

Abstract

This study aims to analyze the effect of station configuration on the results of earthquake source parameter estimates. The data used consists of three-component local waveforms recorded by three IRIS broadband stations belonging to WebDC 3 (SBM, KSM, and KNRA) from 2009 to 2025, specifically for earthquakes that occurred in Sumbawa, West Nusa Tenggara on November 8, 2009, at 09:41:44.8 GMT, with a magnitude of 6.7 at latitude -8.32 and longitude 118.7, at a depth of 18.3 km. Earthquake source parameters were determined using the discrete wave number method to calculate the Greens function and the deconvolution iteration method to invert the moment tensor using local three-component waveforms. This method was implemented in the ISOLA software package. The data were inverted from 0.03 Hz to 0.07 Hz to obtain the earthquake source parameters for the event in that region. The results of the discussion indicate that the configuration of the stations used in the study influences the estimated earthquake source parameters. As the distribution of the seismic stations used approaches an azimuth of 180, the estimated earthquake source parameters become more accurate and align more closely with the Global CMT. It was also found that this study identified the primary causes of the earthquakes as normal and strike-slip faults.

Keywords: seismic station configurations, earthquake source parameters, three component local waveforms.

Topic: Earth Physics and Space Science