Crustal properties investigation in the Meratus Complex Zone, Southeast Borneo, using H-κ stacking of receiver function analysis

Abstract

We study crustal properties using teleseismic receiver functions extracted from two broadband seismic stations around the Meratus Complex region, Southeast Borneo. The two seismic stations, BBKI and KBKI, are distributed in the Meratus Mountains and Pulau Laut. We then employ the H-κ stacking technique to measure the crustal thickness (H) and the crustal average Vp/Vs ratio (κ). The method works quite well for receiver functions recorded on seismic station KBKI. The thickness of the crust and Vp/Vs ratio underneath this station are around 38 km and 1.64, respectively. On the contrary, the standard H-κ method fails in estimating the crustal properties beneath station BBKI due to significant sedimentary contamination on the receiver functions. Thus, we apply the sequential H-κ stacking analysis by removing the sedimentary effect and increasing the Moho Ps amplitude. The result shows the thickness of the crust is around 29 km, although the Vp/Vs is not well determined. The research findings from both stations are comparable to those derived from the previous receiver function study using inversion modelling. The crustal properties around this area may reflect the continental material part of the Sunda continental block.