Radiografía de un margen continental utilizando campos potenciales y espesor de sedimentos: el Margen Atlántico Ibérico

M. Catalán; Y. M. Martos; J. Martín-Davila; A. Muñoz-Martín; A. Carbó; M. Druet

doi:10.21701/bolgeomin.126.2-3.010

Authors

M. Catalán Sección de Geofísica, Real Observatorio de la Armada
Y. M. Martos Instituto Andaluz de Ciencias de la Tierra, CSIC-UGR
J. Martín-Davila Sección de Geofísica, Real Observatorio de la Armada
A. Muñoz-Martín Facultad de Ciencias Geológicas; Universidad Complutense de Madrid
A. Carbó Facultad de Ciencias Geológicas; Universidad Complutense de Madrid
M. Druet Instituto Español de Oceanografía

DOI:

https://doi.org/10.21701/bolgeomin.126.2-3.010

Keywords:

Bouguer anomaly, magnetic anomaly, geodynamics, geophysics, Iberian Atlantic margin

Abstract

This study reviews the state of knowledge in the Iberian Atlantic margin. In order to do this, the margin has been divided into three provinces: the Galicia margin, the southern Iberian abyssal plain, and the Tagus abyssal plain. We have used potential field and sediment thickness data. This has allowed us to study the crust, setting limits for the continental crust domain, and the amplitude of the so-called ocean-continent transition, whose end marks the beginning of the oceanic crust. The study shows the continental crust in the Galician margin to be the widest, about 210 km in length, whilst the ocean-continent transition varies slightly in this province: between 65 km wide in the south and 56 km wide in the north. This result shows up some differences with the hypothesis of other authors. The situation in the southern Iberian abyssal plain is nearly the opposite. Its continental crust extends approximately 60 km, whilst the ocean-continent transition zone is 185 km long. The Tagus abyssal plain study shows a faster morphological evolution than the others, according with the amount of crustal thinning ß, the ocean-continent transition domain spanning 100 km. These results support a transitional intermediate character for almost the whole Tagus plain, in contrary to what other authors have stated.

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