Download Scientific news n°460 ( PDF , 1051 Ko)

Actualité scientifique
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Although being able to predict the date on which the next big earthquake will occur is still some way
off becoming a reality, it is now possible to identify the areas where they will occur. IRD researchers
and their French, Ecuadorian and Peruvian partners have just measured the current deformation
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the areas where the fault, located at the interface of these two plates, is capable of generating large
earthquakes or not.
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tectonic structures such as the Bolivian highlands and the Gulf of Guayaquil in Ecuador, with the
discovery of a continental microplate in Peru and southern Ecuador.
Good to know
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causes major earthquakes.
Glossary
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Fault: the boundary between two tectonic blocks or plates on which earthquakes occur.
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Clearly determined seismic areas
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can produce mega-earthquakes (greater
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located in central Peru and the second
is further north, extending from northern
Ecuador to southern Colombia. In between
these two active segments, the research
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the north of Peru to the south of Ecuador, or
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to produce a mega-earthquake. Across the
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and more modest in magnitude, as shown in
recent history.
Andean structures explained
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researchers to discover a large continental
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per year towards the south-east in relation
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deformation of the Andes from Venezuela to
southern Chile, and the seismic activity in
the region are dominated by the movements
of several microplates of that type.
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explains the location of major tectonic
structures. For example, the Bolivian
highlands, the second highest plateau in
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and the central Andes microplate coming
together. In contrast, the opening of the
Gulf of Guayaquil in Ecuador is a result of
the divergence of the Inca block and the
northern Andes microplate.
Coordination
Gaëlle Courcoux
Information and Culture
Department
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of recent developments in the Andes and
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make better estimates of seismic hazards in
the region possible.
www.ird.fr/la-mediatheque
Partners
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Media Contact
References
NOCQUET JEAN-MATHIEU, VILLEGAS-LANZA J. C., CHLIEH
MOHAMED, MOTHES P. A., ROLANDONE F., JARRIN P.,
CISNEROS D., ALVARADO A., AUDIN LAURENCE, BONDOUX
FRANCIS, MARTIN XAVIER, FONT YVONNE, RÉGNIER MARC,
VALLÉE MARTIN, TRAN T., BEAUVAL CÉLINE, MENDOZA J.
M. M., MARTINEZ W., TAVERA H., YEPES H<#b'$!'"#'+#
continental slivers and creeping subduction in the
northern Andes. Nature Geoscience6#JIKG6#Y#NGO6#)<#
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Contacts
Jean-Mathieu Nocquet, IRD researcher
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Indigo, IRD Photo Library
Daina Rechner
Mohamed Chlieh, IRD researcher
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Laurence Audin, IRD researcher
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Géoazur Joint Research Unit
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Photos : www.indigo.ird.fr
ISTerre Joint Research Unit
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First measurement of the deformation in
the northern Andes
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earthquakes ever recorded: on the border
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When will one of these major earthquakes
happen there again? It is impossible to say...
But scientists can now identify the areas
where it will occur. Researchers from the
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and their partners from geophysical and
geographical institutes in Ecuador and Peru,
have just measured the deformation in the
northern Andes caused by the subduction of
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American continental plate. Using a vast
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from central Peru to southern Colombia,
with an accuracy of about one millimetre per
year.