Primarily a tsunami is generated when any natural or artificial force disturbs large volume of water particularly or largely in vertical direction through sea floor. These water waves have very high frequency and very small wavelengths in onshore areas, which causes mass destruction. A submarine or offshore volcanic eruption can produce high magnitude lifts on seafloors, which pushes large water columns upwards to generate tsunami. Submarine volcanoes can be detected by the presence of high rock content and steam above water surface. These submarine volcanoes form high slope pillars over their craters as compared to their on surface counterparts, which is due to the rapid cooling effect of water and buoyancy. The process of tsunami generation in such cases can be understood through the concept of phreatomagmatic eruption. Such an eruption is an explosive interaction between water and magma, which produces fine grained tephra with the emission of magmatic gases and steam. Another considerable fact is the failure of a submarine volcano’s slope which results in sudden disturbance of water resulting in tsunami waves.
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