APPLICATION OF WAVEFORM INVERSION TO DETERMINE FOCAL MECHANISM IN THE NORTHERN SUMATRAN FAULT

• 主要作者: Kuni Sa'idah, Ratu
• 格式: Final Project
• 語言: Indonesia
• 在線閱讀: https://digilib.itb.ac.id/gdl/view/76176
• 機構: Institut Teknologi Bandung

The Great Sumatran Fault (GSF) is a seismically active right-lateral fault and the main intracontinental transcurrent fault in western Indonesia. The 1,900 km long GSF from the south of the Sunda Strait to the Andaman Islands is one of the most active faults in the world. The GSF is a mature fault with an offset of at least 20 km and a dextral slip about 15 mm/yr. Fault monitoring is necessary because the earthquake caused by the GSF is a threat to life because the GSF is in several locations close to dense population centers. One method that can be used is waveform inversion using ISOLA software. This method is used to describe the focal mechanism around GSF. Waveform inversion results of 20 earthquake events around GSF precisely longitude 94-98 and latitude 4-6 indicate that this area has strike slip focal mechanism type which is divided into upper cluster and lower cluster, also dominated by right lateral strike slip with the average strike 281.3, dip 81.5, rake 158.7 for upper cluster and average strike 175.4, dip 83.1, and rake 135.4 for lower cluster. The upper cluster affiliated with the Aceh Central segment which meets the Seulimeum segment, while the lower cluster estimated to be in the Aceh South segment which meets the Batee-A segment.