Active shortening simultaneous to normal faulting based on GNSS, geophysical, and geological data: The seismogenic Ventas de Zafarraya Fault (Betic Cordillera, southern Spain)

The central Betic Cordillera, southern Spain, is affected by an uplift related to the NNW–SSE Eurasia-Nubia convergence and shallow ENE–WSW orthogonal extension accommodated by the extensional system of the Granada Basin. The combination of geophysical, geodetic, and geological data reveals that the...

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Detalles Bibliográficos
Autores: Madarieta Txurruka, A., González Castillo, L., Peláez, J.A., Galindo Zaldívar, J., Borque, M.J., Lacy, M.C., Ruiz Armenteros, A.M., Henares, J., Ruano, P., Sánchez Alzola, A., Avilés, M., Rodríguez Caderot, G., Martínez Moreno, F.J., Tendero Salmerón, V., Vinardell Peña, R., Gil, A.J.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Universidad de Jaén
Repositorio:RUJA. Repositorio Institucional de la Producción Científica de la Universidad de Jaén
OAI Identifier:oai:ruja.ujaen.es:10953/6822
Acceso en línea:https://doi.org/10.1029/2023TC007956
https://hdl.handle.net/10953/6822
Access Level:acceso abierto
Palabra clave:Ventas de Zafarraya fault
GNSS velocity field
Geophysical survey
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Descripción
Sumario:The central Betic Cordillera, southern Spain, is affected by an uplift related to the NNW–SSE Eurasia-Nubia convergence and shallow ENE–WSW orthogonal extension accommodated by the extensional system of the Granada Basin. The combination of geophysical, geodetic, and geological data reveals that the southwestern boundary of this extensional system is a seismically active compressional front extending from the W to the SW of the Granada Basin. The near-field Global Navigation Satellite System data determine NNE–SSW shortening of up to 2 mm/yr of the compressional front in the Zafarraya Polje. In this setting, the normal Ventas de Zafarraya Fault developed as a result of the bending-moment extension of the Sierra de Alhama antiform and was last reactivated during the 1884 Andalusian earthquake (Mw 6.5). The uplift in the central Betic Cordillera together with the subsidence in the Western Alborán Basin may facilitate a westward to southwestward gravitational collapse through the extensional detachment of the Granada Basin. The heterogeneous crust of the Betic Cordillera would generate the compressional front, which is divided into two sectors: thrusting to the west, and folding associated with buttressing to the south. Our results evidence that basal detachments, linking extensional fault activity with compressional fronts, may determine the activity of local surface structures and the geological hazard in densely populated regions.