a New Central American Seismic Zonation
Abstract
A new zonation for Central America is proposed, aimed at providing an input for regional seismic hazard studies. The zonation combined different kind of data: the seismotectonic model, a new an extensive earthquake catalog homogenized to a moment magnitude scale (Mw), focal mechanisms, geomorphologic features, GPS observations and other useful evidences for defining seismic sources. After a careful analysis of the seismicity and tectonics in the study area, the seismogenic zones have been identified, following the usual criteria assumed in probabilistic seismic hazard assessment (PSHA) based in zoning models: seismic activity modelled by a Poisson process and similar patterns of faulting, seismicity, and rupture mechanism inside each zone. The tectonic environment has required taking into account zones in three particular regimes: crustal faulting, subduction interplate and subduction intraplate (inslab). Therefore, three models including zones with different depths have been defined, each model being associated with the seismicity in a particular range: h < 25 km for crustal zones, 25<h<60 km for interplate and h> 60 km for intraplate (inslab). The three models have been proposed for the whole of Central America, and also including zonations at the national level; i.e each country with their own zones based in the knowledge of the local faults and seismicity. A consensus was reached among the researchers to have country detailed zonations, but avoiding discontinuities at the national boundaries. This is the first zonation model for the whole Central America region which also includes detail zonation at the national level. This new zonation allows the generation of seismic hazard maps using a more homogeneous criteria.
- Publication:
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AGU Spring Meeting Abstracts
- Pub Date:
- May 2013
- Bibcode:
- 2013AGUSM.S43B..17C
- Keywords:
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- 7200 SEISMOLOGY