PROBABILISTIC HAZARD EFFECTS OF SEISMIC TSUNAMI IN THE MANILA SUBDUCTION ZONE ONTO SOUTH CHINA COAST
The Manila subduction zone,as a high-risk seismic tsunami source,poses a serious threat to the coast of South China.Probabilistic Tsunami Hazard Assessment(PTHA)will help to fully understand the temporal and spatial distribution of the Manila subduction zone seismic tsunami energy and guide the design and construction of the South China Sea Coastal Project.The probability distribution of five earthquake uncertainty parameters in the Manila subduction zone was studied using the logic tree method to design a catalog set of seismic tsunamis.The non-hydrostatic numerical model was used to simulate the propagation of all the sample scenarios.Finally,the curves of maximum tsunami amplitude hazard for the South China Sea were obtained by the probability calculation,and the spatial distribution of the maximum wave amplitude of the probabilistic tsunami in the South China Sea in 100-year and 500-year regression periods was plotted.It was found that the impact of the potential tsunami for the return periods of 100 years on the southern coast of mainland of China is relatively low,the maximum wave amplitude may reach 0.7 m,and the danger level would exceed Level Ⅱ.The tsunami for the return periods of 500 years possibly poses a Level Ⅲ threat to cities along the southern coast such as Shantou,Shanwei,Hang Kong and Macao,and the maximum amplitudes may reach 2.5 m.The potential tsunami with the maximum amplitude of 3.1 m would occur along the coasts of Zhongsha Islands and Xisha Islands,and the tsunamis with a maximum amplitude of more than 4.0 m could threaten Dongsha Islands possibly.The tsunami danger level for the Zhongsha,Xisha,and Nansha Islands could reach as high as Level Ⅳ.
Manila subduction zoneseismic tsunaminonhydrostatic modelprobabilistic hazard assessmentSouth China Sea
万方数据
维普
