Indo-Australian Plate Velocity Measurement During Interseismic Phase in 2010–2014 Using Sumatran GPS Array (SuGAr) Data

Abstract

AbstractThe movement of the Indo-Australian Oceanic Plate towards the Eurasian Continental Plate in the western part of Sumatra Island causes this area has a high potential for earthquakes. The magnitude of an earthquake depends on the energy accumulation in the interseismic period. This study aims to determine the plate velocity and direction of movement at the stable/interseismic phase during 2010–2014, using Sumatran GPS Array (SuGAr) data. RINEX data from GPS was processed using GAMIT/GLOBK software. There are eight SuGAr observation stations which uses across the west coast of Sumatra Island. The result shows that annual velocity during an interseismic phase of some SuGAr station which are BTHL, MLKN, NGNG, and PTLO stations moved northeastward. The direction of this movement is consistent with the direction of subduction of the Indo-Australian Plate and based on the time series graph, all of SuGAr stations during the annual interseismic phase (2012–2014) indicated stable movement.KeywordsGPSSuGArIndo-Australian PlateInterseismic phaseSumatra