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| Titel |
Large earthquakes in stable continental plate interiors: the need for a new paradigm |
| VerfasserIn |
Eric Calais, Thierry Camelbeeck, Seth Stein |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250096450
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| Publikation (Nr.) |
 EGU/EGU2014-11957.pdf |
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| Zusammenfassung |
| The occurrence of large earthquakes in stable continental plate
interiors has so far resisted our understanding. Contrary to plate
boundary settings, where a balance is achieved over <1000 years
between the rates at which strain accumulates and is released in
large events, intraplate earthquakes occur in regions where no
discernable strain is building up today. In the absence of current
strain accumulation, their triggering mechanism remains elusive,
as well as the mechanism by which faults having already ruptured
in large events might be reloaded to permit sequences of large
events, such as in the New Madrid, Central-Eastern U.S., sequence.
Earthquake activity in such settings does not seem to be persistent
at the location of past large historical earthquakes, which appear
to be episodic, clustered and spatially migrating through time.
The relationship between long-term geological structures and
earthquakes is poorly understood and the ability of intraplate
current producing M3-4 events to rupture in M6 and larger earthquakes
is unknown. Finally, the fact that the steady-state plate boundary
model -- which forms the basis for seismic hazard estimation --
does not seem to hold in continental interiors makes accurate seismic
hazard estimation in such setting particularly challenging. We
will review these issues and argue that our understanding of
earthquakes in continental plate interiors requires a paradigm
shift. |
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