Geodynamics of the central South Atlantic conjugate margins: implications for hydrocarbon potential

Rifted margins: Ductile deformation, boudinage, continentward-dipping normal faults and the role of the weak lower crust

“…In contrast with the Angola margin, the Gabon margin presents a much thicker syn-rift sedimentary cover, and a thinner sag basin (Lentini et al, 2010;Unternehr et al, 2010, Péron-Pinvidic et al, 2015. We present three profiles shot offshore the Gabonese margin.…”

Architecture of rifted continental margins and break-up evolution: insights from the South Atlantic, North Atlantic and Red Sea–Gulf of Aden conjugate margins

“…Seismic interpretation and physical and numerical modelling also indicate that the Atlantic continental margins are characterized by multi-phase rift evolution, and the focus of the final breakup is more often associated with reactivation of extensional faults and magmatic activity (Lentini et al 2010;Huismans & Beaumont, 2011). However, in deep water regions of the South Atlantic these features are most often hidden by a thick layer of salt and post-breakup sediments, and even with deep seismic images the transition from continental to oceanic crust is still elusive in many basins.…”

“…The outermost highs in these basins have not been drilled and alternative interpretations of their origin have been proposed, including volcanic highs, Precambrian horsts, uplifted rifted blocks, and exhumed serpentinized mantle (Lentini et al 2010;Scotchman et al 2010;Unternehr et al 2010;Zalán et al 2011).…”

From orogen to rifted passive margin formation in Brazil: Geodynamic numerical modeling considering the effects of structural inheritance and rheology

“…Heine et al, 2013) have shown that extension of the lithosphere must have occurred following nonuniform stretching models, that is, depth-dependent extension (e.g. Beaumont, 2011, 2014;Lentini et al, 2010). Depth-dependency causes the lithosphere to stretch differently with depth, so in some domains the crust might be hyper-extended (> 100 km, Unternehr et al (2010)), whereas in other domains, mantle lithosphere could be exhumed.…”

“…Resulting brittle deformation due to uniform stretching (pure-shear models) seems to underestimate the magnitude of lateral extension needed to create very thick sag basins (Lentini et al, 2010;Reston, 2010) Figure 4.5 -Free-air gravity filtered image (Heine et al, 2013) of the South Atlantic Rift System showing its four main segments and bounding fracture zones.…”