强潮汐激发地震火山活动的新证据

强潮汐与火山地震活动密切相关. 天文资料表明, 2000年6月到8月日本Izu半岛最活跃的火山地震活动正好处于天文大潮时期和日长变化最小值时期. 在厄尔尼诺事件和拉尼娜事件发生前后，东西太平洋海面高度分别升降40cm, 水均衡作用使洋壳反向升降13cm. 由此形成的东西太平洋地壳跷跷板运动加强了强潮汐对地震火山活动的激发作用.

New evidence of earthquake and volcano triggering by strong tides

At the end of June in 2000, volcanic and seismic events started at the Izu islands south to Tokyo. Following the events, extraordinary crustal deformation was observed around the Izue islands. Until the end of August, both the volcanic and seismic activities were high. It is suggested that the crustal deformation was caused by a dyke intrusion event at the Izu islands and associated with strong tides. A tidal model triggering earthquakes and volcanoes is proposed based on the observational data and calculation results. Before and after the El Nino event and La Nina event, the oceanic water in East Pacific Ocean and West Pacific Ocean may rise or fall 60cm oppositely, which make the oceanic crust fall or rise 20cm. It is the reason that the El Nino events and La Nina events are interrelated with the earthquakes and volcanoes. This phenomenon is just like "see-saw" motion. Strong tide and El Nino are the excitation condition of earthquakes and volcanoes activities.