ANALYSIS OF MOLLUCCA SEA SHALLOW STRUCTURE USING SEISMIC TOMOGRAPHY

• Main Author: Corleon Nasution - NIM : 12313049, Dennis
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/26490
• Institution: Institut Teknologi Bandung

<p align="justify">Molucca Sea Zone is an area where there is an active collision between two arcs of the Sangihe and Halmahera that produce high central ridge marked by intense of shallow-depth seismicity and low gravity anomalies. An earthquake and its aftershocks occurred on November 15, 2014 which are distributed on the Molucca Sea ridge. The earthquake and its aftershocks totaled 183 earthquake events and were recorded by 18 stations during November 15 to November 30, 2014. From the travel times data of all event, a seismic tomography study was conducted to determine the structures of P wave, S wave, and Vp/Vs ratio. The velocity structures illustrate the structure of the Molucca Sea Zone at shallow depths. Both of Vp and Vs structures indicate there is a high anomaly associated with the Halmahera arc under the Sangihe arc associated with low velocity anomalies. The result of Vp/Vs shows a high Vp/Vs value associated with the crack zone characterized by the number of earthquakes in that zone.<p align="justify">