BUSCADOR RECOLECTA

Apatite fission track and zircon (U-Th)/He, Low-temperature thermochronology studies have increased our knowledge of the orogenic processes along the Pyrenean-Cantabrian mountain belt by placing time constraints on the exhumation history of its rocks. However, a significant gap of data existed between the Pyrenees and the Cantabrian Mountains, hampering a comprehensive view of the tectonothermal evolution along the belt. Thus, we present a new apatite fission-track (AFT) and zircon (U-Th)/He (ZHe) dataset for the eastern Basque-Cantabrian zone and western Pyrenees. AFT central ages cluster in the Eocene-Oligocene. According to their ZHe age-eU correlations, samples can be separated into two groups: group 1 depicts clustered ZHe ages-eU concentrations (Cinco Villas Massif) and group 2 depicts dispersed ZHe ages-eU concentration (Alduides Massif and a Paleozoic rock pinned along the Leiza thrust sheet). A sample from the Oroz-Betelu Massif shows an intermediate behavior. Our results agree with previous data in the Pyrenean-Cantabrian mountain belt, supporting a Cenozoic cooling of the hinterlands of this part of the belt., Funding sources: University of Oviedo-Banco Santander (grant number UNOV-10-BECDOC-S, Programa de Promoción de la Investigación Universidad de Oviedo-Banco Santander); Gobierno del Principado de Asturias Fundación para el Fomento en Asturias de la Investigación Científica Aplicada y la Tecnología (FICYT), grant number BP11-004, Beca predoctoral Severo Ochoa; Spanish Ministry of Science, Innovation and Universities (AP2010-3637, Programa de Formación del Profesorado Universitario, FPU); Spanish Ministry of Science and Innovation (grant number CSD2006-00041, Consolider-Ingenio); European Science Foundation; Consejería de Cultura y Deporte Gobierno del Principado de Asturias; French National Centre of Scientific Research; The Research Council of Norway; Statoil-Hydro; Netherlands Research Center for Integrated Solid Earth Science (grant number SV-PA-10-03-IP2-PYRTEC, PYRTEC: Spatial and temporal coupling between tectonics and surface processes during lithosphere inversion of the Pyrenean-Cantabrian mountain belt); Ministerio de Ciencia, Innovación y Universidades (grant number CGL2013-48601-C2-2-R, Programa Estatal de I+D Programa de Investigación, desarrollo e innovación orientada a los retos de la sociedad)., Peer reviewed

The total amount of seismic data were 11 profiles N-S, E-W and NW-SE oriented raging between 70 and 250 km. The signal was recorded in a network of 24 OBS/OBH instruments and 36 land stations. Technical specifications of the profiles: Streamer length: 2400 m; Group numer: 96; Group interval: 25 m; Source: air guns; Record length: 18 s; Sample rate: 4 ms., MARCONI (MARgen COntinental NordIberico - North Iberian Continental Margin) is a deep seismic reflection survey carried out in the southeastern part of the Bay of Biscay in September 2003. It included the acquisition of 11 multichannel deep seismic reflection profiles covering a total length of 2000 km. The overall goal of the multichannel experiment was to collect seismic data to unravel the structure and evolution of the southern margin of the Bay of Biscay in relation to the Mesozoic tectonic extension and collision and inversion of extensional faults in the context of the Alpine orogeny., Funder: Ministerio de Ciencia y Tecnología. Grant name: Reconocimiento geológico y gefísico del margen continental noribérico: estudio integrado de las cuencas sedimentarias y de la evolución geodinámica del golfo de Vizcaya y de la cordillera cántabro-pirenaica REN-2001-1734-C03-01., Peer reviewed

Two onshore profiles were acquired in E-W and N-S directions through the Variscan and Alpine domains of 140 and 65 km length, ESCI-N1 and ESCI-N2 respectively. Also two offshore profiles ESCI-N3 and ESCI-N4 were obtained with a streamer of 4500 m having 360 channels with a 12.5 m gap between them and a 40 l airgun capacity. ESCI-N3 follows a swerved line in a mainly E-W direction crossing the Variscan structures. ESCI-N4 is a N-S direction profile that crosses both the Cantabrian margin and Le Danois bank Alpine structures. Techincal specifications of offshore profiles: streamer length 4,500 m, 360 channels, group interval 12,5 m and sample rate 4 ms., The ESCI-N project in Northwestern Spain was a subprogram of the ESCI Program (Estudios Sísmicos de la Corteza Ibérica). It is formed by four seismic experiments both on and offshore. This project aimed to image the Cantabrian Zone, West Asturian-Leonese Zone and the northern Iberian margin, thus characterizing the crustal structure resulted from the Variscan and Alpine orogenies and the Mesozoic extension related to the opening of the Bay of Biscay., CICYT (Committee of Science and Technology of the Spanish Ministry of Education and Science), GEO90-0660.-- FICYT (Fundación para el Fomento en Asturias de la Investigación Científica Aplicada y la Tecnología).-- Science and Technology for Regional Innovation and Development in Europe-European Commission, Peer reviewed