Arc-parallel vs back-arc extension in the Western Gibraltar arc : is the Gibraltar forearc still active?

Extremely tight arcs, framed within the Eurasia-Africa convergence region, developed during the Neogene on both sides of the western Mediterranean. A complex interplate deformation zone has been invoked to explain their structural trend-line patterns, the shortening directions and the development of...

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Detalles Bibliográficos
Autores: Balanyá, J. C., Crespo Blanc, Ana|||0000-0003-3723-2529, Díaz-Azpiroz, M., Expósito Barea, Isabel|||0000-0002-2084-5487, Torcal, F., Pérez-Peña, José Vicente|||0000-0001-8880-7375, Booth-Rea, G.
Tipo de recurso: artículo
Fecha de publicación:2012
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:99650
Acceso en línea:https://ddd.uab.cat/record/99650
https://dx.doi.org/urn:doi:10.1344/105.000001771
Access Level:acceso abierto
Palabra clave:Forearc tectonics
Strain partitioning
Crustal earthquakes
Gibraltar arc
Descripción
Sumario:Extremely tight arcs, framed within the Eurasia-Africa convergence region, developed during the Neogene on both sides of the western Mediterranean. A complex interplate deformation zone has been invoked to explain their structural trend-line patterns, the shortening directions and the development of back-arc basins. Updated structural and kinematic maps, combined with earthquake data covering the complete hinge zone of the western Gibraltar arc help us to explore the mode of strain partitioning from 25My ago to present. During the Miocene, the strain partitioning pattern showed arc-perpendicular shortening in the active orogenic wedge -assessed from the radial pattern of tectonic transport directions- accompained by subhorizontal stretching. Structures accommodating stretching fall into two categories on the basis of their space distribution and their relationships with the structural trend-line pattern: i) arc-parallel stretching structures in the external wedge (mainly normal faults and conjugate strike-slip faults); and ii) extensional faults developed in the hinterland zone in which transport directions are centripetal towards the Alborán back-arc basin. Pliocene to Recent deformational structures together with focal solutions from crustal earthquakes (n=167; 1.5.