ATTENUATION EQUATION FOR THE HORIZONTAL AVERAGE PEAK GROUND ACCELERATION IN SUNDANESE ARC SUBDUCTION ZONE (MEGATHRUST)

• Main Author: SANTOSO (NIM: 22415003), EDY
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/26850
• Institution: Institut Teknologi Bandung

<p align="justify">Sundanese Arc Subduction Zone (megathrust) is an active and historically disastrous area of large destructive earthquake. This zone extends from Andaman Island to the Northwest and Banda Arc to the west with a length of about ± 3000 km. Subduction zone is produced from a collision between Indo – Australia plate and Southeast Asian plate. Indo-Australian plate dips into the bottom of the Southeast Asian plate. The Attenuation equation in the Sundanese Arc Subduction Zone (megathrust) has not been widely developed in Indonesia. So, it still refers to the attenuation equation in other subduction zone area. For this reason, we need to developed the attenuation equation in Sundanese Arc Subduction Zone (megathrust) and mapping of the model in affected area due to the earthquake. The database consist of 71 earthquake event with total amount 1236 data. The PGA value used for calculation of the attenuation equation is derived from average value of a horizontal component record. The method used to two step stratified regression analysis procedure. Attenuation equation which has physically calculated the saturation of the acceleration amplitude in the near source area of the earthquake and has simple point source characteristics including geometric spreading over medium to long distances. The attenuation equations for the combined segments in Sundanese Arc Subduction Zone (megathrust) are : <br /> <br /> (attenuation function) <br /> <br /> Where A is the horizontal average peak ground acceleration (cm/sec2), M is the moment magnitude (Mw), and R is the distance of the hypocenter (km). The implementation of the attenuation equation of studies in the mapping of affected areas due to earthquake in the Sundanese Arc Subduction Zone (megathrust) is closer to observational data than subduction attenuation equations else.<p align="justify">