Structure and tectonic evolution of the eastern Cantabrian marginResults from the MARCONI multichannel seismic data .

  1. Fernández-Viejo, G 1
  2. Gallastegui, J 1
  3. Pulgar, J. A. 1
  1. 1 Universidad de Oviedo
    info

    Universidad de Oviedo

    Oviedo, España

    ROR https://ror.org/006gksa02

Revista:
Trabajos de geología

ISSN: 0474-9588

Año de publicación: 2009

Número: 29

Páginas: 260-265

Tipo: Artículo

Otras publicaciones en: Trabajos de geología

Resumen

The Bay of Biscay formed during the Cretaceous as a consequence of the opening of the North Atlantic. The convergence between the Iberian and Eurasian plates during the Cenozoic resulted in its partial closure and the building of the Pyrenean-Cantabrian Mountains on land. Most of this deformation and shortening at the south-easternmost part of the Bay of Biscay concentrated in the North Iberian Margin, making this area a unique place to study the initial stages of deformation in a passive margin. In summer 2003, 11 deep seismic reflection profiles were acquired in the MARCONI seismic experiment, providing a new 3D image of the structure of the bay. This new dataset shows that the structure of this margin is characterized by a thick sequence of Mesozoic-Cenozoic sediments (up to 4 s TWT, up to 6 km) partially deformed by northward vergent thrusts and related folds. The interpretation includes three sedimentary sequences separated by unconformities that correspond to the pre-, syn- and post-tectonic units. A Mesozoic sedimentary basin imaged has indications of a Cenozoic tectonic inversion. Evidences of lateral and/or transfer structures coincide with two important N-S striking submarine canyons. The overall crustal structure of the south-easternmost part of the Bay of Biscay has been interpreted as a thinned continental or transitional crust underthrusted to the S below the extremely steep North Iberian continental slope.

Referencias bibliográficas

  • ÁLVAREZ-MARRÓN, J., PÉREZ-ESTAÚN, A., DAÑOBEITIA, J. J., PULGAR, J. A., MARTÍNEZ-CATALÁN, J. R., MARCOS, A., BASTIDA, F., AYARZA-ARRIBAS, P., ALLER, J., GALLART, J., GONZÁLEZLODEIRO, J., BANDA, E., COMAS, M. and CÓRDOBA, D. (1996): Seismic structure of the northern continental margin of Spain from ESCIN deep seismic profiles. Tectonophysics, 264: 153-174.
  • ÁLVAREZ-MARRÓN, J., RUBIO, E. and TORNÉ, M. (1997): Subduction related structures in the North Iberian Margin. J. Geophys. Res., 102: 22497-22511.
  • FERNÁNDEZ-VIEJO, G., GALLART, J., PULGAR, J. A., CÓRDOBA, D. and DAÑOBEITIA, J. J. (1998): Crustal transition between continental and oceanic domains along the North Iberian margin from wide angle seismic and gravity data. Geophys. Res. Lett., 25: 4249- 4252.
  • GALLASTEGUI, J., PULGAR, J. A. and GALLART, J. (2002): Initiation of and active margin at the North Iberian continent-ocean transition. Tectonics, 21, 4. doi:10.1029/2001TC901046.
  • OLIVET, J. L. (1996): La cinematique de la plaque Iberique. B. Centres Res. Explor. Prod. Elf-Aquitanie, 20: 131-195.
  • PULGAR, J. A., GALLART, J., FERNÁNDEZ-VIEJO, G., PÉREZ-ESTAÚN, A., ÁLVAREZ-MARRÓN, J. and ESCIN GROUP (1996): Seismic image of the Cantabrian Mountains in the western extension of the Pyrenean belt from integrated reflection and refraction data. Tectonophysics, 264: 1-19.
  • RUIZ, M. (2007): Caracterització estructural i sismotectònica de la litosfera en el domini Pirenaico-Cantàbric a partir de mètodes de sísmica activa i passiva. PhD Thesis, Barcelona University, Spain, 354 pp.
  • SRIVASTAVA, S. P., ROEST, W. R., KOVACS, L. C., OAKEY, G., LEVESQUE, S., VERHOEF, J. and MACNAB, R. (1990): Motion of Iberia since the Late Jurassic: Results from detailed aeromagnetic measurements in the Newfoundland basin. Tectonophysics, 184: 229-260.