ESTIMATION OF SOURCE PARAMETER FOR LOCAL EARTHQUAKES ON PALU-KORO FAULT AND ITS TECTONIC IMPLICATION

• Main Author: WIJAYA BIDANG (NIM : 22411310); Pembimbing : Afnimar, Ph.D, ANDRI
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/25560
• Institution: Institut Teknologi Bandung

Palu-Koro fault which is an active seismic zone in Central Sulawesi, is divided into seven segments. The seismicity of the Palu-Koro fault during the period of 1974-2013 shows that the segments of II, III, and IV (region I) had more frequent earthquakes than the segment I (region II) did. Most of the earthquakes in these regions were small magnitude shallow earthquakes. Therefore, these regions are interested to study. A spectrum analysis is applied on vertical component of P-wave displacement after instrument response and path corrections. By using grid search method, the source parameters such as seismic moment, corner frequency and quality factor are determined by fitting the Brune model. The momen magnitude, source radius, and stress drop can be calculated from these source parameter values. We obtain a linear relationship between momen magnitude and local magnitude M W = 0 .73 9 1M L + 1 .77 8 6 . For the same seismic moment range, the stress drop value in the region I is higher than the region II. Therefore, it could be said that the material in region I is stronger than in the region II.