Seismic site response of submarine slope offshore southwestern Taiwan

Jing Yi Lin, Yen Fu Chen, Chih Chieh Su, Shao Jinn Chin, Win Bin Cheng, Wen Nan Wu, Chin Wei Liang, Hsin Sung Hsieh, Shu Kun Hsu, Yi Chin Lin

研究成果: 雜誌貢獻期刊論文同行評審

9 引文 斯高帕斯(Scopus)


Widely distributed Bottom-Simulating Reflectors (BSRs) have been observed in the area offshore of southwestern Taiwan where the active accretionary complex meets with the passive China continental margin. In order to clarify the link between seismic site response and sedimentary properties of submarine slope, we evaluate the response of seafloor sediments in regard to passive dynamic loads. The local site effect produced by shallow marine sediments was characterized by estimating the horizontal-to-vertical (H/V) spectral ratios of data recorded by the short-period Ocean Bottom Seismometers (OBSs). The results show that the maximal H/V ratios appeared in the range of 3.66 - 9.28 Hz, suggesting that the fundamental frequency is dominated by the effect related to the very shallow sediments. For most stations, the H/V ratios estimated based on the earthquakes and noise records were characterized by different patterns. Relatively broad H/V pattern was obtained when the signals were extracted from earthquakes. This phenomenon may be related to soil nonlinearity when a stronger motion applies. In comparison with the available geological structures and bulk density distribution obtained from coring experiments, we found a relatively higher fundamental frequency of about 8 - 9 Hz for the more rigid material, such as mud diapir and folding axes. For most of the area along the slope, the fundamental frequency shows a relatively low value, about 6 - 8 Hz. Finally, when a site is characterized by thick or lowest bulk density sedimentary layer, we observed a fundamental frequency lower than 5 Hz, which is the lowest in our assessment.

頁(從 - 到)51-63
期刊Terrestrial, Atmospheric and Oceanic Sciences
出版狀態已出版 - 2月 2018


深入研究「Seismic site response of submarine slope offshore southwestern Taiwan」主題。共同形成了獨特的指紋。