Early-Middle Miocene subtle compressional deformation in the Ebro foreland basin (northern Spain); insights from magnetic fabrics

The results of anisotropy of magnetic susceptibility analyses of 19 sites carried out on magnetostrigraphically-dated, Lower to Middle Miocene (20.4 to 13.7 Ma) 'non-deformed' mudstones from the central part of the Ebro basin reveal the presence of a subtle tectonic overprint lasting at le...

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Detalles Bibliográficos
Autores: Soto, Ruth, Larrasoaña, Juan C., Beamud Amorós, Elisabet, Garcés Crespo, Miguel
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2016
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/164275
Acceso en línea:https://hdl.handle.net/2445/164275
Access Level:acceso abierto
Palabra clave:Magnetisme
Miocè
Ebre, Conca de l'
Deformació de les roques
Magnetism
Miocene
Ebro River Watershead
Rock deformation
Descripción
Sumario:The results of anisotropy of magnetic susceptibility analyses of 19 sites carried out on magnetostrigraphically-dated, Lower to Middle Miocene (20.4 to 13.7 Ma) 'non-deformed' mudstones from the central part of the Ebro basin reveal the presence of a subtle tectonic overprint lasting at least until the Langhian (Middle Miocene) in the southern Pyrenean foreland. Magnetic ellipsoids show a sedimentary fabric in 42% of sites and a weak and well-defined magnetic lineation in 47% and 11% of sites. The magnetic lineation is roughly oriented around the east-west direction, compatible with a very weak deformation occurring there and related to the north-south compression linked to the convergence between Europe, Iberia and Africa during the Early-Middle Miocene. A slight variation of the magnetic parameters Km, Pj, and T exists through time, probably due to changes in the sedimentary conditions in the basin.