New Field Insights Into the 2018 M7.5 Palu, Indonesia Earthquake and Tsunami and a Comparison with the 2009 M8.1 Samoa Event

Session: Understanding Non-Traditional Seismic Tsunami Hazards [Poster]
Type: Poster
Date: 4/28/2020
Time: 08:00 AM
Room: Ballroom
Description: 

A deadly Mw 7.5 earthquake struck the island of Sulawesi, Indonesia on 28 September 2018, causing over 2000 fatalities and the destruction of several areas within and around Palu city. The intensities on the Modified Mercalli Intensity (MMI) scale reached a maximum value of XI in villages located directly along the fault, as well as some villages located up to 12 km SE of Palu city. Strong ground shaking along the southern and eastern shores of Palu Bay lead to the complete collapse of some single-story houses that were constructed of timber as well as wide-spread damage of two- and three-story houses constructed with unreinforced concrete. Earthquake-induced soil liquefaction and landslides were highly localized but very damaging, as well as a major cause of death. We present the results of a seismic intensity survey that was conducted independently by us on 12–19 October 2018. Our dataset covers a much larger area than in previously published studies, with a total of 173 sites visited, extending 150 km N–S and 50 km E–W. Although tsunami run-up maps have been published, to our knowledge, no seismic intensity maps have been previously presented for the Palu event. We compare and contrast our findings with the 2009 M_w 8.1 Samoa earthquake and the resultant tsunami that occurred in a region with a coastline whose shape is similar to that of Palu Bay.

Presenting Author: Marcella Cilia

Authors