Modeling of a dispersive tsunami caused by a submarine landslide based on detailed bathymetry of the continental slope in the Nankai trough, southwest Japan

被引：21

作者：

Baba, Toshitaka ^{[1
]}

Gon, Yodai ^{[1
]}

Imai, Kentaro ^{[2
]}

Yamashita, Kei ^{[3
]}

Matsuno, Tetsuo ^{[4
]}

Hayashi, Mitsuru ^{[5
]}

Ichihara, Hiroshi ^{[6
]}

机构：

[1] Tokushima Univ, Grad Sch Technol Ind & Social Sci, 2-1 Minami Jyosanjima Cho, Tokushima 7708506, Japan

[2] Japan Agcy Marine Earth Sci & Technol, Res & Dev Ctr Earthquake & Tsunami, 3173-25 Showa Machi, Yokohama, Kanagawa, Japan

[3] Tohoku Univ, Int Res Inst Disaster Sci, Aoba Ku, 468-1 Aoba, Sendai, Miyagi 9808572, Japan

[4] Kobe Univ, Kobe Ocean Bottom Explorat Ctr, Higashinada Ku, 5-1-1 Fukaeminami, Kobe, Hyogo 6580022, Japan

[5] Kobe Univ, Res Ctr Inland Seas, Higashinada Ku, 5-1-1 Fukaerninami, Kobe, Hyogo 6580022, Japan

[6] Nagoya Univ, Earthquake & Volcano Res Ctr, Grad Sch Environm Studies, Chikusa Ku, Nagoya, Aichi 4648601, Japan

来源：

TECTONOPHYSICS | 2019年 / 768卷

基金：

日本学术振兴会;

关键词：

Tsunami; Submarine landslide; Directivity; Dispersion; Nankai trough; MASS-TRANSPORT DEPOSITS; NEW-GUINEA TSUNAMI; JULY; 1998; EARTHQUAKE; GENERATION; SIMULATION;

D O I：

10.1016/j.tecto.2019.228182

中图分类号：

P3 [地球物理学]; P59 [地球化学];

学科分类号：

0708 ; 070902 ;

摘要：

Tsunamis caused by submarine landslides are not accompanied by seismic waves and thus may appear at the coast without warning. In this study, detailed bathymetric surveys with a multi-narrow beam echo sounder were used to map submarine landslides on the continental shelf near Cape Muroto, in the Nankai trough off southwestern Japan. One of the surveyed submarine landslides was selected to supply dimensions for the simulation of a submarine mass movement by a two-layer flow model in which the upper and lower layers correspond to seawater and turbidity currents, respectively. The time series of seafloor deformation during this simulated landslide was used as the boundary condition to drive a tsunami simulation. The results showed strong directivity effects during tsunami generation in which pushing-dominant (positive) tsunami waves propagated seaward, in the direction of the submarine landslide, and pulling-dominant (negative) tsunami waves propagated landward. Both types of waves were strongly modified by frequency dispersion. For pulling-dominant waves, a tsunami simulation that included dispersion (Boussinesq) terms predicted greater maximum tsunami heights than a non-dispersive tsunami simulation. To avoid underestimation of tsunami heights, we recommend including dispersion terms when modeling tsunamis caused by submarine landslides for disaster planning purposes.

引用

页数：10

共 42 条

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