Tsunami Overland Flow Characteristic and Its Effect on Palu Bay Due to the Palu Tsunami 2018

摘要

On September 28, 2018, Palu Earthquake caused tremendous damage to the coastal area of Palu, Central Sulawesi, Indonesia. The epicenter was located at 27 km northeast from Donggala Beach with a 10 km depth. The magnitude of the earthquake was recorded at 7.4. This study assessed the tsunami overland characteristics and its outcome on the coastal area of Palu. The analysis was conducted based on satellite images and video recordings. The satellite images taken prior and post the event, were analyzed to evaluate the morphological change along the coast. The shoreline retreated up to 158 m in some places. The tsunami damaged infrastructures along the affected coastal area. Video recordings were collected and analyzed to assess the tsunami overland propagation. The data were verified by field survey. The arrival time and celerity of the wave propagation overland on open area and the urban area were studied. It was found that buildings in the urban area have a significant impact on celerity. The wave propagates faster in the open area than inside the building.