A more realistic slope failure scenarios underneath the Makassar Strait and its potency to cause tsunami around the eastern part of Kalimantan
Rizqi Valentra (a*), Rima Rachmayani (b), Benyamin Sapiie (c)

a) Earth Science Study Program, Faculty of Earth Science, Bandung Institute of Technology, Bandung, Indonesia
*rizqi.valentra[at]gmail.com
b) Oceanographic Research Group, Faculty of Earth Science, Bandung Institute of Technology, Bandung, Indonesia
c) Geodynamics and Sedimentology Research Group, Faculty of Earth Science, Bandung Institute of Technology, Bandung, Indonesia

Abstract

Gigantic Mass Transport Deposits were found underneath the Makassar Strait during a research in 2020. These deposits were formed 2.6 Mya and assumed as the products of submarine landslide events. Through a closer look at the interior and the exterior part of the largest deposit found, it was found that this deposit formed in a very slow movement of mass that transported little by little forming hundreds of kilometers cubic deposit. It is safe to say that these giant deposits are not tsunamigenic. However, these finding did not eliminate the possibility of the slope on the west side of the Makassar Strait being failed. While trying to examine the largest MTD, this research found much smaller size deposits that might move faster that those with huge volume. Through NHWAVE and FUNWAVE, these deposits could cause a VII - VIII class tsunami on some area in the East Kalimantan. This tsunami can cause few people washed away, small vessels damaged, and wooden buildings demolished. Though the scenarios were still rough and the resolution of bathymetry data used could be improved, the result of this research could be used as a preliminary to examine the tsunami hazard on the affected areas since these places located really close to the soon to be capital city of Indonesia.

Keywords: Makassar Strait- Submarine Landslide- Tsunami Model

Topic: Ocean Sciences