Formation and subsequent inversion of extensional salt-detached ramp-syncline basins developed above ramp-flatramp faults

• Main Author: Roma Nuñez, Maria
• Other Authors: Muñoz, J. A., Ferrer García, J. Oriol (José Oriol), Universitat de Barcelona. Departament de Dinàmica de la Terra i de l'Oceà
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Universitat de Barcelona 2020
• Subjects: Conques sedimentàries; Tectònica salina; Sedimentary basins; Salt tectonics; North Atlantic
• Online Access: http://hdl.handle.net/2445/180212; http://hdl.handle.net/10803/672461

[eng] The widespread extensional deformation that took place during Jurassic to Cretaceous times in Western Europe and the North Atlantic margin resulted in the formation of several rift systems. Some of the resulting basins associated with these rifts show broad synclines detached on pre- or synkinematic Permian or Triassic salts and filled by thick sedimentary successions. They are rarely fault bounded, instead they are bounded by salt structures that are generally parallel to the major subsalt structures. As such, the formation of these extensional systems requires the presence of i) a subsalt extensional fault with significant dip changes and ii) an evaporitic unit above the extensional fault, which partially or completely decouples the suprasalt basin from the subsalt extensional fault. Moreover, the complexity of these scenarios further increases when some of these basins, during latest Cretaceous and Cenozoic times, were partially inverted or incorporated into fold-and-thrust belt.Synclinal basins have a significant exploration potential when their extensional geometry is preserved and when they have undergone positive tectonic inversion. However, in some cases, their subsalt geometry may not be fully recognizable, especially when the imaging of the subsalt seismic data is poor. The shape and kinematics of such faults have usually been established using the architecture of synkinematic units and by assuming complete coupling of the hangingwall rocks. Therefore, there are fault interpretations that do not consider the role of deep salt layers, which clearly act as an effective detachment, decoupling sub- and suprasalt deformations.This thesis provides a review of the formation and evolution extensional synclinal basins and an overview of the widespread-recognized salt-detached ramp-syncline basins. To obtain a deeper understanding of the geometry and kinematic evolution of these salt- detached ramp-syncline basins, the principal aim of this thesis is to decipher the factors that are involved in the ...