Numerical Simulation of the 2010 Mentawai Tsunami: Interpretation of the Field Survey in Pagai Island

Abstract

There was an M 7.7 Mentawai-Indonesia earthquake on October 25th 2010 at 14.42 (Western Indonesia Time), and a tsunami was detected. The paper aims to compare the tsunami numerical model to a field report of the undertaken by a BMKG Team a few days after the occurrence of a tsunami invading the western coast of Mentawai (Indonesia). The tsunami caused severe damage and claimed many victims in some coastal villages. The field survey was to measure the inundation and the run-up values as well as to ascertain the possible morphological changes caused by the wave attacks. We did a numerical model using TUNAMI-N2 and divided four regions with Pagai Utara islands as the main focus on the modeling. Most places were hit by three significant waves with documented wave height often exceeding 5 m. The maximum run-up value (17.00 m) was on-site measured at North Pagai, where also the most impressive erosion phenomena could be found.