Non-linear waveform analysis for water-layer response and its application to high-frequency receiver function analysis using OBS array

作者：Akuhara Takeshi^*; Mochizuki Kimihiro; Kawakatsu Hitoshi; Takeuchi Nozomu

来源：Geophysical Journal International, 2016, 206(3): 1914-1920.

DOI：10.1093/gji/ggw253

• Body waves
• Computational seismology
• Subduction zone processes

Determination of a response of the sea water column to teleseismic plane wave is important to suppress adverse effects of water reverberations in calculating receiver functions (RFs) using ocean-bottom seismometer (OBS) records. We present a novel non-linear waveform analysis method using the simulated annealing algorithm to determine such a water-layer response recorded by an OBS array. We then demonstrate its usefulness for the RF estimation through its application to synthetic and observed data. Synthetic experiments suggest that the water-layer response constrained in this way has a potential to improve RFs of OBS records drastically even in the high-frequency range (to 4 Hz). By applying it to data observed by the OBS array around the Kii Peninsula, southwestern Japan, we identified a low-velocity zone at the top of the subducting Philippine Sea plate. This zone may represent the incoming fluid-rich sediment layer that has been reported by active-source seismic survey.

• 出版日期2016-9