“3.11”日本地震海啸及南海和琉球群岛假想地震海啸对福建近海影响的数值模拟

福建地处西北太平洋沿岸,在环太平洋地震带附近,是海啸灾害潜在风险区.＂3.11＂日本地震海啸,福建沿岸验潮站就监测到其海啸波.利用CTSU地震海啸数值模式,模拟了＂3.11＂日本地震海啸对福建近海的影响,模拟结果与实况较吻合.同时,利用该数值模式模拟分析了可能来自于琉球群岛和南海附近海域的地震海啸对福建近海的影响,分析表明,如果在琉球群岛海域（28.0°N,129.0°E）发生8.8级地震,引发的海啸波将在4.5 h左右抵达福建北部海岸,最大海啸波幅可达2 m;如果在马尼拉海沟附近海域（17.5°N,119.0°E）发生8.8级地震,引发的海啸波将在4 h左右抵达福建南部海岸,最大海啸波幅可达3 m,均会给福建沿海地区带来灾害性影响.为此,本文亦针对性提出了防范地震海啸的一些措施与建议,为福建省海洋防灾减灾提供参考.

Numerical simulation of the effect of the "3.11" Japan earthquake tsunami and the hypothetical earthquake tsunami at South China Sea and the Ryukyu Islands on Fujian offshore area

Located in the northwest Pacific coast,Fujian is near the central Pacific seismic belt,which is the potential risk area of tsunami disaster.Fujian offshore tidal station monitored the tsunami leading waves triggered by the ＂3.11＂ Japan earthquake tsunami.Adopting the CTSU model,this paper simulated the ＂3.11＂ Japan earthquake tsunami and analyzed its influence on Fujian offshore area.The results agreed well with the monitored records.At the same time,this paper simulated and analyzed the effect brought about by the possible South China Sea and the Ryukyu Islands earthquake tsunami upon Fujian offshore area.The analyses show that if a Mw8.8 earthquake occurs at the adjacent waters of the Ryukyu Islands,the tsunami leading waves will arrive at the northern Fujian offshore area 4.5h later,with a maximum tsunami leading wave amplitude up to 2m;if a Mw8.8 earthquake occurs at the Manila Trench,the tsunami leading waves will arrive at the northern Fujian offshore area 4h later,with a maximum tsunami leading wave amplitude up to 3 m.To better prepare and respond to the disastrous effects,this paper puts forward some suggestions and measures on marine disaster prevention and mitigation,which can provide reference for Fujian Province.