Showing posts with label Earthquake. Show all posts

Friday, September 6, 2013

6th International Conference on Fractals and Dynamics Systems in Geoscience. Perugia, Italy

Japan-UNESCO/UNU Symposium on The Great East Japan Tsunami on 11 March 2011 and Tsunami Warning Systems: Policy Perspectives

16 - 17 February 2012, Tokyo, Japan

The Great East Japan Earthquake and Tsunami on 11 March 2011 caused nearly 20,000 people to lose their lives.
Since the event many national and international post-tsunami field surveys have been carried out. Performance analyses of tsunami early warning systems in place at the time of this event have also been done. Based on these surveys and performance analyses the symposium will offer a number of invited high level perspectives from decision makers and scientists and address topics including:

- Event facts and analysis
- Tsunami Warning Systems, Tsunami preparedness and event experiences
- What has been learned from this event and policy implications.

Third Announcement of the Japan – UNESCO/UNU Symposium (English version)

More information here

Friday, June 17, 2011

Interesting articles - NatureGeoscience /May-Jun

Tectonics: Unexpected Andean earthquakes

Nadine McQuarrie

Nature Geoscience 4, 357–358 (2011) doi:10.1038/ngeo1167


Published online 31 May 2011

Great earthquakes along the western, subduction zone boundary of the Andes Mountains in South America are expected. Measurements of surface motion along the eastern boundary highlight the potential for equally large earthquakes in the east.

Subject terms:

Structural geology, tectonics and geodynamics

Link to the paper

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Orogenic-wedge deformation and potential for great earthquakes in the central Andean backarc

Benjamin A. Brooks, Michael Bevis, Kelin Whipple, J Ramon Arrowsmith, James Foster, Tomas Zapata, Eric Kendrick, Estella Minaya, Arturo Echalar, Mauro Blanco, Pablo Euillades, Mario Sandoval & Robert J. Smalley Jr

Affiliations Contributions Corresponding author
Nature Geoscience 4, 380–383 (2011) doi:10.1038/ngeo1143

Published online08 May 2011

Subduction of the Nazca plate beneath South America has driven the growth of the Andes Mountains. Subduction has routinely generated earthquakes larger than magnitude 8.0 along the western margin of the mountain belt¹, but the potential size of less frequent earthquakes in the eastern, backarc margin is unknown. Continued support of the high Andean Plateau at the centre of the Andes can be explained only if deformation of the backarc margin is ongoing^{2, 3, 4}. Here we present GPS data that record surface motions in the Subandean ranges that are part of the backarc margin. We find that the velocity of surface movement decreases sharply from west to east across the Subandean ranges. We suggest that a subhorizontal fault underlying the ranges slips freely at depth in the west, but is locked for up to 100 km in shallower sections further east. Analysis of fault scarps formed where the subhorizontal fault intersects the surface indicates that the fault has generated repeated large earthquakes. We suggest that rupture of the entire locked section of the fault could generate an earthquake of magnitude 8.7–8.9. We attribute the large seismic potential to the unusual width of the Subandean ranges, and suggest that deformation of the Subandean ranges, at a rate unmatched by erosion, causes the mountain range to widen.