Magnetobiochronology of Lower Pliocene marine sediments from the lower Guadalquivir Basin: Insights into the tectonic evolution of the Strait of Gibraltar area

Article Article scientifique Article Magnetobiochronology of Lower Pliocene marine sediments from the lower Guadalquivir Basin: Insights into the tectonic evolution of the Strait of Gibraltar area eng 2018 author Pérez Asensio José Noel 811502 author Larrasoaña Juan C. author Samankassou Elias 0000-0003-0385-7686 636960 author Sierro Francisco J. author Garcia-Castellanos Daniel author Jiménez-Moreno Gonzalo author Salazar Ángel author Maria Salvany Josep author Ledesma Santiago author Mata M. Pilar author Civis Jorge author Mediavilla Carlos 1791-1808 10.1130/B31892.1 0016-7606 https://pubs.geoscienceworld.org/gsa/gsabulletin/article/530891/Magnetobiochronology-of-Lower-Pliocene-marine The Gibraltar Arc is a complex tectonic region, and several competing models have been proposed to explain its evolution. We studied the sedimentary fill of the Guadalquivir Basin to identify tectonic processes that were occurring when the reopening of the Strait of Gibraltar led to the reestablishment of Mediterranean outflow. We present a chronostratigraphic framework for the Lower Pliocene sediments from the lower Guadalquivir Basin (SW Spain). The updated chronology is based on magnetobiostratigraphic data from several boreholes. Our results show that the studied interval in the La Matilla core is in the early Pliocene section, providing better constraints on the sedimentary evolution of the basin during that period. Migrating depositional facies led to a younger onset of sandy deposition basinward. At the northwestern passive margin, a 0.7 m.y. period of sedimentary bypass related to a sharp decrease in sedimentation rates and lower sea levels resulted from the tectonic uplift of the forebulge. In contrast, high sedimentation rates with continuous deep-marine sedimentation are recorded at the basin center due to continuous tectonic subsidence and west-southwestward progradation of axial depositional systems. The marginal forebulge uplift, continuous tectonic basinal subsidence, and southward progradation of clinoforms in the early Pliocene can be explained by the pull of a lithospheric slab beneath the Gibraltar Arc as the Strait of Gibraltar opened. These findings are, to our knowledge, the first reported sedimentary expression of slab pull beneath the Betics related to the opening of the Strait of Gibraltar after the Messinian salinity crisis. Lower Pliocene Lower Guadalquivir Basin Tectonic evolution Strait of Gibraltar area Mediterranean outflow Magnetochronology Dewey 550 42 Département des sciences de la Terre 154 false Geological Society of America Bulletin 130 11-12 e04662bd-38d2-4a90-b04e-fc969b255014 Article (Published version) Restricted Perez_Asensio_Et_Al_2018.pdf 3717588 application/pdf restrictedAccess Faculté des sciences / Section des sciences de la Terre et de l'Environnement / Département des sciences de la Terre

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Magnetobiochronology of Lower Pliocene marine sediments from the lower Guadalquivir Basin: Insights into the tectonic evolution of the Strait of Gibraltar area	Geological Society of America Bulletin			2018	435	0

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Pérez Asensio, José Noel