Depth Estimation of Moho Discontinuity Layer at 5 BMKG Seismic Stations in East Java Using Receiver Function Method

Abstract

East Java is one of the areas with a high level of seismicity due to the existence of a subduction zone in the south of Java Island. In addition, there are also active faults and active volcanos in East Java. This study aims to determine the depth of the Moho Discontinuity layer and subduction slab using receiver function method based on the iterative time domain deconvolution. This study was conducted using teleseismic earthquake data with an epicenter distance of 30°–90° from the receiver station and magnitude more than 6 (M≥6). 5 BMKG seismic stations that form a straight line are used, including those in the Bawean Arc (BWJI), Rembang Zone (BAJI), Kendeng Zone (SIJM), Modern Mountain Arc (PPJI), Southern Mountain Zone (GEJI). The depth of the Moho Discontinuity layer at BWJI Station was observed in ranges from 36–38 km, at BAJI Station it ranges from 39–40 km, at SIJM Station it ranges from 39–40 km, at PPJI Station it ranges from 46–48 km, and at GEJI Station it ranges from 33–36 km. In general, the Moho Discontinuity layer in the mountainous region is deeper due to the isostasy effect.