Andreas Wittwer

Tectonic Framework of the Central Java Subduction Zone: This Work is Based on Data of the Joint Interdisciplinary Meramex (Merapi Amphibious Experiment) Project Andreas Wittwer

The tectonic framework of the central Java subduction zone is presented in this study. Three marine wide-angle seismic profiles are analyzed by combined forward- and inverse modeling of first and later arrival traveltimes and are integrated together with marine gravity data. The subduction of the oceanic Roo Rise plateau, located south of central Java, with its thickened and buoyant crust, strongly influences subduction dynamics. The incipient subduction of a broad band of seamounts causes frontal erosion of the margin and leads to mass wasting due to oversteepening of the upper trench wall. The rough surface of the Indo-Australian lithosphere with its volcanic edifices affects the interplate coupling. Seamounts and similar features present on the megathrust may potentially act as asperities to seismic rupture, limiting lateral rupture propagation.