IAG-IASPEI 2017

Presentation information

Poster

IASPEI Symposia » S14. Upper mantle and transition zone dynamics and structure

[S14-P] Poster

Thu. Aug 3, 2017 3:30 PM - 4:30 PM Event Hall (The KOBE Chamber of Commerce and Industry, 2F)

3:30 PM - 4:30 PM

[S14-P-08] Shear-wave velocity model of Palawan, Philippines from receiver function analysis

Arianne Gail Rivera1, Takuo Shibutani2 (1.Philippine Institute of Volcanology and Seismology, 2.Disaster Prevention Research Institute, Kyoto University)

Palawan Island is located southwest of the Philippine archipelago. Northern Palawan is part of the rifted continental margin of Eurasian plate while southern Palawan comprised the Palawan Ophiolite Complex. The crustal thickness and the regional velocity model beneath the two broadband seismic stations of the Philippine Seismic Network (PSN) in Palawan have been estimated using receiver function analysis.

Teleseismic waveforms data (30 degrees < x < 85 degrees) with magnitude 6.0 and above recorded by the PSN from January 2012 to September 2015 were used in the computation. Using the extended-time multitaper technique, the receiver functions (RFs) were calculated. Consequently, the transverse components of the stacked RFs from all available back-azimuths were inverted using genetic algorithms to check for the presence of any dipping interfaces. This was followed by the inversion of the radial components to have a more defined velocity model for certain back-azimuths.

Results showed that northern Palawan has thinner crust compared to southern Palawan. This can probably be attributed to the differences in their geology. There is also an observed velocity jump observed on both stations that could be the seismic basement.