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USGS · 70156824

Earthquake mechanism and seafloor deformation for tsunami generation

Abstract

Tsunamis are generated in the ocean by rapidly displacing the entire water column over a significant area. The potential energy resulting from this disturbance is balanced with the kinetic energy of the waves during propagation. Only a handful of submarine geologic phenomena can generate tsunamis: large-magnitude earthquakes, large landslides, and volcanic processes. Asteroid and subaerial landslide impacts can generate tsunami waves from above the water. Earthquakes are by far the most common generator of tsunamis. Generally, earthquakes greater than magnitude (M) 6.5–7 can generate tsunamis if they occur beneath an ocean and if they result in predominantly vertical displacement. One of the greatest uncertainties in both deterministic and probabilistic hazard assessments of tsunamis is computing seafloor deformation for earthquakes of a given magnitude.

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BibTeXRIS

Eric L. Geist, David D. Oglesby. 2014-09-24. Earthquake mechanism and seafloor deformation for tsunami generation. https://doi.org/10.1007/978-3-642-36197-5_296-1

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