78808 20221004075832.0 doi 10.1029/2018TC005153 sideral 108575 ART-2018-108575 eng Izquierdo-Llavall, E. Universidad de Zaragoza (orcid)0000-0002-5159-8140 Rotational Kinematics of Basement Antiformal Stacks: Paleomagnetic Study of the Western Nogueras Zone (Central Pyrenees) 2018 Access copy available to the general public Unrestricted The structure of the Pyrenean Axial Zone laterally transitions from an imbricate thrust system to an antiformal stack displaying downward facing structures in its frontal part (the Nogueras zone). We carried out a paleomagnetic study through this structural transition to better constrain thrust kinematics and better define the factors controlling the occurrence of antiformal stacks. Triassic red beds unconformably overlying the Paleozoic basement were sampled across three main thrust sheets (the Nogueras zone, the Bielsa, and the Orri thrust sheets). From 31 new sites, two meaningful magnetizations were defined, both carried by hematite: (1) the primary magnetization, that unblocks at 660–685 °C and (2) an intermediate-temperature, syn-orogenic remagnetization. Paleomagnetic data indicate variable, clockwise vertical axis rotations, with mean, thrust-scale values that range from 0 to +38°. They increase both from the base to the top of the stacked units and from west to east and display a thrust-scale directional dispersion that is higher for the lower wavelength thrusts. Results evidence that increasing thrust displacements in the upper thrusts units are a key factor for the formation of antiformal stacks showing downward facing structures. Displacement gradients in the basement are transferred to cover units and can account for important rotations such as those registered by the Mesozoic-Cenozoic units to the south of the study area. info:eu-repo/grantAgreement/ES/MEC/FPU-AP2009-0554 info:eu-repo/grantAgreement/ES/MICINN/CGL2006-05817 info:eu-repo/grantAgreement/ES/MICINN/CGL2009-08969 info:eu-repo/grantAgreement/ES/MINECO/CGL2009-10840 info:eu-repo/grantAgreement/ES/MINECO/CGL2012-38481 info:eu-repo/semantics/openAccess by-nc-nd http://creativecommons.org/licenses/by-nc-nd/3.0/es/ 3.975 2018 GEOCHEMISTRY & GEOPHYSICS 14 / 84 = 0.167 2018 Q1 T1 2.371 2018 Geophysics 2018 Q1 Geochemistry and Petrology 2018 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Casas-Sainz, A.M. Universidad de Zaragoza (orcid)0000-0003-3652-3527 Oliva-Urcia, B. (orcid)0000-0003-1563-6434 Villalaín, J.J. Universidad de Zaragoza Pueyo, E. Universidad de Zaragoza (orcid)0000-0002-0504-2352 Scholger, R. 2000 428 Universidad de Zaragoza Dpto. Ciencias de la Tierra Área Geodinámica Interna 37, 10 (2018), 3456-3478 Tectonics Tectonics 0278-7407 5015866 http://zaguan.unizar.es/record/78808/files/texto_completo.pdf Versión publicada 2884037 http://zaguan.unizar.es/record/78808/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:78808 articulos driver 2022-10-03-13:16:58 ARTICLE