Open AccessAn iterative algorithm for separation of S and ScS waves of great earthquakes
Author(s) -
Yu Zhulin,
Ni Sidao,
Wei Shengji,
Zeng Xiangfang,
Wu Wenbo,
Li Zhiwei
Publication year - 2012
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.2012.05603.x
Subject(s) - seismology , geology , slowness , waveform , seismic wave , earthquake simulation , algorithm , seismic energy , computer science , telecommunications , radar
SUMMARY Teleseismic SH waves are essential for imaging the rupture processes of large earthquakes. However, for great earthquakes ( M 8+) such as the 2004 Sumatra earthquake, the 2008 Wenchuan earthquake and the recent Tohoku‐Oki earthquake, the source duration is very long (>100 s). Thus the direct SH waves are overlapped with ScS waves for epicentral distances larger than 60°, leaving contaminated S waves for source processes modelling. Therefore artefacts in finite fault models of large earthquake could be produced with such contaminated body waves. We propose an iterative algorithm based on the slowness information of S and ScS waves and stacking technique, to separate S and ScS waves with records from a regional seismic network. Tests on various synthetic data sets show that the algorithm is effective in retrieving teleseismic SH waveforms from complicated wave trains containing both S and ScS . Separation of waveforms for the 2008 Wenchuan earthquake with our algorithm clearly demonstrates the influence of ScS energy, suggesting necessity of recovering S waves.