Fig. 3: Comparison between the recorded and synthetic waveforms.
From: Ultra-low-velocity anomaly inside the Pacific Slab near the 410-km discontinuity
a, b Comparison between the recorded (black) and synthetic waveforms (blue and red) for paths SS1’ of event 20091010. The blue waveforms in (a) are calculated for the FWEA1818 model and the red waveforms in (b) are computed for model “FWEA18-LVZ” derived in this study (see Fig. 4) using a finite-difference simulation code20. The horizontal arrows mark amplitude mismatches between the recorded and FWEA18 waveforms. The vertical arrows mark the presence of a second P-wave pulse. c, d Similar comparison for paths SS2’ of event 20091010. e, f Similar comparison for event 20110804. g, h Similar comparison for event 20090407. Note that a reduced velocity of 10.1, 9.8, and 9.7 km/s has been applied for events 20091010, 20110804, and 20090407, respectively. The synthetic waveforms of the depth phases (i.e., the large negative pulses in e-h) are not shown for the shallow events.
