Source of the 2019 Mw6.9 Banten Intraslab earthquake modelled with GPS data inversion
Satrio Muhammad Alif, Erlangga Ibrahim Fattah, Munawar Kholil, Ongky Anggara
Abstract
The 2019 MW6.9 Banten Intraslab earthquake occurred at ∼100 km to the northeast of the Sunda Trench with two nodal plane models estimated by the Global Centroid-Moment-Tensor (GCMT) Project with a strike of 200° and a dip of 65°.Continuous GPS data from 11 GPS sites were used to model the source of the earthquake in three-components. The coseismic displacements and its uncertainties are obtained from the coordinates of these GPS sites from 7 days before to 7 days after the earthquake. The coseismic slip is the inversion result of those displacements based on the best fit in an elastic half-space. The maximum displacement is ∼5 cm with a large uncertainty that is comparable to the amplitude of displacement. A seismic moment of the best model (strike of 65° and dip of 54°) is 2.79 × 1019 Nm or equivalent to MW6.89. The fault model of the earthquake is highly presumed as a continuation of Sumatran Fault Zone.