Figure 4
Tsunami-induced perturbations of the seafloor electromagnetic field and pressure recorded at the seafloor array network.
Pressure perturbations were recorded using a differential pressure gauge (DPG) at Site 8 (top) and the vertical magnetic field perturbations were recorded by electromagnetometers at all nine stations. The tsunami was associated with the 2010 Chilean earthquake, which occurred at 0634 on 27 February (red triangle). The first arrival signal recorded by the DPG was caused by the seismic wave. The tsunami arrived at the network ~10 hours after the event. All waveforms were high-pass filtered at 0.0002 Hz. The sea-bottom pressure recorded by the differential pressure gauge (DPG) was corrected for the frequency response19 and the in situ amplitude response of predicted ocean tides26. Black and red dots show the peak of the main phase of the tsunami. Black arrows indicate the reverse peak of the initial phase preceding the positive peak of the main phase of the tsunami.
