Relación entre la reología cortical y la crisis sísmica de Ossa de Montiel
- S. Martín-Velázquez 1
- R. Pérez-López 2
- J. López-Gutiérrez 2
- J. Giner-Robles 3
- J.V. Cantavella-Nadal 4
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1
Universidad Rey Juan Carlos
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2
Instituto Geológico y Minero de España
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3
Universidad Autónoma de Madrid
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- 4 Instituto Geográfico Nacional, Ministerio de Fomento
ISSN: 1576-5172
Année de publication: 2016
Titre de la publication: IX CONGRESO GEOLÓGICO DE ESPAÑA
Número: 16
Pages: 499-502
Type: Article
D'autres publications dans: Geotemas (Madrid)
Résumé
The seismic activity related to the Ossa de Montiel earthquake (Mw 4.7; 23rd February 2015) gathered at 11- 12 km depth. We have combined the study of the crustal strength and the vertical distribution of this seismicity to find out the rheological characteristics of the crust that conditioned these hypocentral locations. The crust in Campo de Montiel has two brittle layers, one in the upper crust (up to 7.6 km depth with granite or 9.6 km with quartzite) and another in the middle crust (10.5-14.2 km depth). The seismogenic thickness increases with seismic strain rates and even a continuous layer of 15.5 km develops with a metamorphic upper crust. 158 of the 563 aftershocks recorded show low location errors (maximum error 3 km and average error 1.2±0.7 km) and the 95% occurred in the range of 10-14 km. Therefore, the crustal rheological structure constrained the seismicity within the thin brittle layer of the middle crust and determined the hypocentral depths during this seismic period. The main event took place at the bottom of this brittle layer whereas the aftershocks developed to the top.