COSEISMIC SLIP DISTRIBUTION OF THE 2020 Mw 6.8 BENGKULU EARTHQUAKE DERIVED FROM THE GNSS OBSERVATIONS

On August 18, 2020, an M W 6.8 earthquake occurred ~130 km southwest of Bengkulu. In this study, we used the static GNSS data from continuously monitoring stations, surrounding the epicentre, to obtain the data from 10 days before to 10 days after the earthquake. We estimate the coseismic slip distribution with two models of nodal planes from the USGS. The coseismic slip was calculated using an elastic half-space model with inversion best-fit displacement. The GNSS displacement data with values less than ~5 mm indicate an insignificant displacement and the best model arameters of strike of 313° and dip of 8°, with a misfit value of ~0.4 mm. This study suggests that the 2020 Bengkulu earthquake occurred due to the subduction of the Indo-Australian plate underneath the Eurasian plate with a cumulative seismic moment of 1.73·10 19 N·m, equivalent to magnitude 6.76.