Active tectonic deformation in Java, Indonesia inferred from a GPS-derived strain rate

We investigated the active tectonic deformation in Java using Global Positioning System (GPS) velocity data from 2008 to 2013. We calculated strain rate and estimate that, in general, Java experiences a large strain rate (> 1 microstrain/yr) with an extensional strain (~ 5 microstrain/yr) associated with the ongoing postseismic deformation of the 2006 Java tsunami earthquake. A large compressional dilatation rate fault zone (< -3 microstrain/yr) was estimated along the Cimandiri and Cipamingkis faults in West Java, Jakarta fault in Jakarta, Kendeng fault extending from Central Java to the east up to the Madura Strait, and volcanic activity in Banten and Yogyakarta. A large maximum shear strain rate (> 1 microstrain/yr) was estimated along the Wongsorejo and the Montong faults in East Java, and the Lasem fault in Central Java. We show that our strain rate estimation is able to identify active tectonic regions in Java.