Interplate coupling along the Java trench from CGPS observation

Friday, 19 December 2014
Irwan Meilano1, Henri Kuncoro1, Susilo Susilo2, Joni Efendi3, Hasanuddin Zainal Abidin1, Andri D Nugraha4 and Sri Widiyantoro5, (1)Bandung Institute of Technology, Bandung, Indonesia, (2)Badan Informasi Geospasial, Cibinong, Indonesia, (3)Geospatial Information Agency Indonesia, Cibinong, Indonesia, (4)Bandung Institute of Technology, Global Geophysics Research Group, Bandung, Indonesia, (5)Institut Teknologi Bandung, Bandung, Indonesia
Interplate seismogenic zones along the Java trench were estimated by using continuous GPS observation from South of Lampung in the west to Lombok Island in the east. The observation period starting from 2010 to 2013 with more than 60 CGPS observation stations. The GPS analysis indicates that present-day deformation of Java Island is controlled by rotation of Sunda land, extension in the southern Strait of Sunda, postseismic deformation of the 2006 earthquake and the coupling between Indo-Australian plate and Sunda land. Strain rate solutions indicate compression in the south of Java Island. Using elastic dislocation theory the estimated interplate seismozonic coupling in the Java trench is about 50 percent in the sunda strait, smaller in the south west java and become larger to the east. Slip deficit on subduction interface has important implication for seismic hazard of Java Island.

Keywords: CGPS observation, Interplate Seismogenic, Java Trench