Volcanism - Tsunamis Flashcards
Tsunami
Rapid displacement of water up to 800km/h and 10s metres high
Wave energy stopped deep within water Column, destructive power transport wave across ocean with high efficiency and large volume with tail
Volcangenic tsunami
Paris, 2015
Generated by volcanic debris avalanches up to 1000skm displacing water
Shorted period waves but greater dispersion than seismic
Less frequent
Uzen, Japan - 15,000 deaths 0.3 Debris
Tsunami warning system
1) monitor volcanic activity/earthquakes, seisometers
2) pressure sensor on ocean floor to detect tsunami - data from satellite buoy
3) tide gauges, monitor sea level at shore
DATA COMBINED and MODELLED to forecast arrival
Casualties lower than earthquake but recent krakatau tide gauge didn’t work
Krakataua, 1883
VEI = 6
Formed by the stratovolcano collapsing into the Water, caldera formation
Collapse due to unstable structure, discontinuities, hydrothermal alterations
= mass movement collapse = tsunami
Krakatoa 1883 tsunami facts
Volume rose 40 in
40 m waves
36,000 deaths
Krakatoa, 2018
Difficult to predict, only a few minutes
Volcano related mass failure and associated land slides
Tide gauges helped to research
Stimulated wave form model
Help to understand process and wave properties
Mohammad
2020
2020
Mohammad
Modelling Krakatoa 2018
Krakatoa 2018 facts
14 m run up
400 deaths
VEI 1/0
1883
Alaska cook inlet
Krakatoa
Beget
2008
Beget, 2008
Augustine volcano, 0 deaths
6-8 m the wave from debris avalanche as summit collapsed northward
Inlet had a natural tide and tsunami occurred in low tide so wave only to 0.5m above height tide
2002
Stromboli
2015
Paris
Paris 2015
Volcanogenic tsunami definition
Stromboli 2002,
2 slope failures run up along coast
One of the most tsunamgenic volcanoes in the world
5 tsunamis in 20th century
