Seismic stratigraphy of the offshore basins of Argentina : characterization and modeling of the South Atlantic passive margin dynamics

• Main Author: Lovecchio, Juan Pablo
• Other Authors: IFP Energies nouvelles (IFPEN), Sorbonne Université, Universidad de Buenos Aires, Philippe Joseph, Victor A. Ramos
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: HAL CCSD 2018
• Subjects: Rifting; Gondwana; Atlantic; Mésozoïque; Atlantique; Argentine; Modélisation; Colorado; Malvinas; [SDU.STU]Sciences of the Universe [physics]/Earth Sciences; Afuera; Argentina; South Atlantic Ocean
• Online Access: https://tel.archives-ouvertes.fr/tel-03126562; https://tel.archives-ouvertes.fr/tel-03126562/document; https://tel.archives-ouvertes.fr/tel-03126562/file/2018SORUS506.pdf

This work is focused on basin formation and evolution in the Argentinean South Atlantic Margin and the Mesozoic breakup of SW Gondwana. Rifting evolution was studied in the Malvinas and Colorado/Salado basins. Three superimposed rifting events were identified in the latter. The first rifting event is associated with the Late Triassic extensional reactivation of Late Paleozoic thrusts of the Ventania-Cape fold belt. A second and main rifting stage (Early-Middle Jurassic) is related to faults forming the main depocenters and intersecting the older structures. Finally, Early Cretaceous extension linked to the opening of the South Atlantic Ocean focused on the outer continental fringe and produced emplacement of SDRs. The rifting evolution of the Malvinas basin was seismically characterized. New zircon U-Pb ages constrain rifting in the Jurassic. A new model for Gondwana breakup is presented with focus on the evolution of the Mesozoic peri-Atlantic basins. The post-breakup evolution of the Argentinean South Atlantic margin was also studied via seismic interpretation and stratigraphic characterization. Three stages of drift evolution were identified. After the Hauterivian/Barremian breakup, the Cretaceous drift unit is conditioned by the thermal subsidence over the main depocenters. Only after the Maastrichtian-Danian regional transgression, the margin becomes a single continental platform. The Paleogene drift stage is characterized by subsidence and sedimentary input centered in the Salado area, while the Neogene drift stage is characterized by a cylindrical behavior and the remarkable influence of contour currents. Ce mémoire traite de la formation et de l'évolution des bassins de la marge Atlantique argentine. Trois stades de rifting superposés ont été identifiés dans les bassins des Malvinas et de Colorado/Salado. Le premier événement de rifting est associé à la réactivation extensive, durant le Trias tardif, des chevauchements paléozoïques de la phase de Ventania-Cape. Un deuxième stade de rifting (Jurassique ...