GEOSCAN, résultats de la recherche


AuteurCassidy, J F
SourceEncylopaedia of natural hazards; par Bobrowsky, P T (éd.); Encyclopedia of Earth Sciences Series vol. 41, 2013 p. 208-223
Séries alt.Secteur des sciences de la Terre, Contribution externe 20100066
Documentpublication en série
Sujetssecousses séismiques; mécanismes de tremblement de terre; études séismiques; magnitudes des séismes; géophysique
Illustrationslocation maps; photographs; tables
ProgrammeTargeted Hazard Assessments in Western Canada, Géoscience pour la sécurité publique
Résumé(disponible en anglais seulement)
Earthquakes are one of the most frightening natural phenomena that occur. They shake our very foundation - the ground beneath our feet. They almost always strike without warning. The shaking, in the form of aftershocks, can continue for days, weeks, months, or even years. The effects of earthquakes can be widespread (a tsunami caused by a large earthquake can damage regions tens of thousands of km's away) and wide-ranging (strong shaking, fires, landslides, liquefaction). Each year, several million earthquakes occur around the world, including about 20,000 that are large enough to be located, and, on average, more than 1300 that are large enough (magnitude (M) greater than 5) to cause some damage. As the world's population continues to expand, losses and deaths from earthquakes are climbing rapidly, particularly in developing countries. In this article we briefly summarise the causes of earthquakes, the history of earthquakes, the effects of earthquakes, how earthquakes are monitored and studied, and what can be done to protect ourselves from, and reduce the impact of, future earthquakes.