Registro geofísico e interpretación sísmica de estructuras extensionales y compresivas en el Margen Continental Noribérico

Résumé

The North Iberian margin represents a unique setting to study the formation and the geodynamic evolution of a passive margin and to analyse the influence of rift inheritance on subsequent compressional reactivation. Relying on a dense set of borehole-constrained seismic reflection data and on the integration of published velocity models, we develop a tectono-strati- graphic assessment of the seismic records and produce crustal and sediment thickness maps. Seismic-derived interpretations and isopach maps have enabled the definition of different crustal domains and sedimentary basins, which are bounded by high-angle normal faults, strike-slip faults, extensional detachment faults and thrusts. The margin shows a strong structural variability which is also observed in crustal thickness and Moho depth maps derived from 3D constrained gravity inversions. The quality of the seismic imaging has allowed us to define the basement features associated with all the distinctive structures and analyse their seismic expression. This work shows that the geological-geophysical interpretation of seismic data is the cornerstone to unravel the architecture of a passive margin and its along-strike structural variability, providing key insights to constrain the kinematic evolution of conjugate rifted margins.