Evaluation of potential hazards from teletsunami in China: Tidal observations of a teletsunami generated by the Chile 8.8 M w earthquake

Abstract

At 14:34 Beijing time on February 27, 2010, an earthquake of M w 8.8 rocked the central coast of Chile. A teletsunami was triggered by the huge earthquake and then propagated across the entire Pacific in less than 24 h. The initial tsunami wave arrived at the southeast coast of China at 16:20 on February 28 and was recorded in real time by a number of tidal gauges off mainland China and Taiwan Province. The teletsunami waves have never been recorded with such a broad geographical scope in China before this event. The aim of the present work is to report the first description of sea-level oscillations generated by the Chile tsunami, and evaluate the potential hazards that teletsunami poses to the coast of China. The results reveal that the east coast of Taiwan Province, Zhejiang Province and the north coast of Fujian Province are vulnerable to transoceanic tsunami. In addition, spectral and wavelet analysis of the recorded sea-level oscillations shows that “seiches” are easily excited by the resonance resulting from the interaction between the initial tsunami waves and local geometry (such as semi-enclosed bays and ports). The superimposition of the two oscillations would amplify the wave height further.