Modelling of Potential Tsunami in Makassar Strait, Indonesia: Submarine Landslide-Induced Tsunami Simulations

Abstract

Tsunami modelling of potential landslide-induced tsunami in Makassar Strait is carried out to quantify possible damage to the nearby cities. Two numerical models are used to represent the wave generation and propagation by using NHWAVE and FUNWAVE models, respectively. The simulations consist of a series of scenarios based on distinct size of the landslide volume. Four landslides with volume 5, 8, 70, and 200 km 3 are used as tsunami sources in the initiation stage. The sources are evenly distributed in the Strait addressing different landslide location. Maximum wave heights of 1.5 m are found in the area between Palu and Bangkir from case 1 and around Talok from case 2 simulations. The empirical run-up calculation of 7.5 m is estimated at the land for the presented wave height. The value significantly elevates the case 3 and 4 proportional to the volume values. The waves impact more than half of coastline with maximum value found in the Sulawesi side. Interestingly, wide and narrow shelf next to Kalimantan Island plays an important role in reducing the tsunami hazard level.

Probabilistic Landslide Tsunami Estimation in the Makassar Strait, Indonesia, Using Statistical Emulation

“…Notably, this is an area of particular risk due to its proximity to the announced location of the de facto capital city. This is further exacerbated by a number of additional factors all contributing to the oversteepening and destabilization of the continental slope: sediment erosion and deposition generated by the Makassar Throughflow currents, sediment influx from the Mahakam River, carbonate growth, and frequent proximal seismic events (Brackenridge et al., 2020; Gumbira et al., 2021; Hutchings & Mooney, 2021).…”

“…Research aiming to simulate the tsunamigenic landslide events in the Makassar Strait has generally followed scenario‐based methodologies (e.g., Gumbira et al., 2021; Pranantyo et al., 2021). To develop the aforementioned scenario‐based deterministic methodologies into a probabilistic tsunami hazard analysis within the Makassar Strait region requires the production of a catalog of synthetic (but realistic) tsunami events, involving the probabilistic sampling of key parameters.…”