Dispersive tsunami of the 2010 Chile earthquake recorded by the high-sampling-rate ocean-bottom pressure gauges

作者：Saito Tatsuhiko^*; Matsuzawa Takanori; Obara Kazushige; Baba Toshitaka

来源：Geophysical Research Letters, 2010, 37: L23303.

DOI：10.1029/2010GL045290

Cabled ocean-bottom pressure gauges deployed offshore Japan recorded the pressure change associated with the 2010 Chile earthquake tsunami over a wider frequency range than that of coastal tide gauges or hydrophones. Although it was difficult to recognize the dispersive features in the original records, the spectrograms clearly showed wave dispersion. A low-frequency tsunami (similar to 1 mHz) arrived after an elapsed time of 24 hr from the earthquake origin time, while a high-frequency tsunami (similar to 9 mHz) arrived after an elapsed time of 48 hr. The arrival times can be explained by assuming a constant water depth of 4 km. However, the calculated waveform does not correctly reproduce the number of wave packets appearing in the observations. Cabled ocean-bottom pressure gauges deployed offshore can record broadband tsunami signals reflecting the wide-wavenumber-range spatial spectrum for sea-bottom deformation caused by the earthquake. Citation: Saito, T., T. Matsuzawa, K. Obara, and T. Baba (2010), Dispersive tsunami of the 2010 Chile earthquake recorded by the high-sampling-rate ocean-bottom pressure gauges, Geophys. Res. Lett., 37, L23303, doi:10.1029/2010GL045290.

• 出版日期2010-12-4