2024-03-28T13:07:02Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1589792022-10-10T07:29:54Zcom_10261_82com_10261_8com_10261_262578col_10261_335col_10261_262579
Pedrera Parias, Antonio
García Senz, Jesús María
Ayala, C.
Ruiz Constán, Ana
Rodríguez Fernández, Luis Roberto
Robador Moreno, Alejandro
González Menéndez, Luis
2018-01-11T09:02:17Z
2018-01-11T09:02:17Z
2017-12
Tectonics, 36(12): 3155–3177 (2017)
0278-7407
http://hdl.handle.net/10261/158979
10.1002/2017TC004716
1944-9194
http://dx.doi.org/10.13039/501100003339
Recent models support the view that the Pyrenees were formed after the inversion of a previously highly extended continental crust that included exhumed upper mantle rocks. Mantle rocks remain near to the surface after compression and mountain building, covered by the latest Cretaceous to Paleogene sequences. 3-D lithospheric-scale gravity inversion demands the presence of a high-density mantle body placed within the crust in order to justify the observed anomalies. Exhumed mantle, having ~50 km of maximum width, continuously extends beneath the Basque-Cantabrian Basin and along the northern side of the Pyrenees. The association of this body with rift, postrift, and inversion structural geometries is tested in a balanced cross section across the Basque-Cantabrian Basin that incorporates a major south-dipping ramp-flat-ramp extensional detachment active between Valanginian and early Cenomanian times. Results indicate that horizontal extension progressed ~48 km at variable strain rates that increased from 1 to ~4 mm/yr in middle Albian times. Low-strength Triassic Keuper evaporites and mudstones above the basement favor the decoupling of the cover with formation of minibasins, expulsion rollovers, and diapirs. The inversion of the extensional system is accommodated by doubly verging basement thrusts due to the reactivation of the former basin bounding faults in Eocene-Oligocene times. Total shortening is estimated in ~34 km and produced the partial subduction of the continental lithosphere beneath the two sides of the exhumed mantle. Obtained results help to pinpoint the original architecture of the North Iberian Margin and the evolution of the hyperextended aborted intracontinental basins. ©2017. American Geophysical Union
eng
openAccess
Basque-Cantabrian Basin
Lithospheric-scale extensional detachment
Oblique rifting
Peridotites Shale
Salt tectonics
Reconstruction of the Exhumed Mantle Across the North Iberian Margin by Crustal-Scale 3-D Gravity Inversion and Geological Cross Section
artículo