0000000000940869
AUTHOR
Andrea Buta-neto
Segmentation and differential post-rift uplift at the Angola margin as recorded by the transform-rifted Benguela and oblique-to-orthogonal-rifted Kwanza basins.
29 pages; International audience; We analyse tectonic and sedimentary field and subsurface data for the Angola onshore margin together with free-air gravity anomaly data for the offshore margin. This enables us to characterize the mode of synrift tectonism inherited from the Precambrian and its impact on the segmentation of the Angola margin. We illustrate that segmentation by the progressive transition from the Benguela transform-rifted margin segment to the oblique-rifted South Kwanza and orthogonal-rifted North Kwanza margin segments. The spatial variation in the intensity of post-rift uplift is demonstrated by the study of a set of geomorphic markers detected in the post-rift succession…
Distribution of Albian clastic deposits in the Benguela basin (Angola): evidence of a Benguela palaeocurrent?
Abstract The Albian clastic Tuenza Formation of the Benguela basin (south Angola) is described and its geographic distribution analysed in detail. From these observations, the existence of an Albian “PalaeoBenguela current” is proposed. This would imply that a marine longshore current reworked the sand transported by palaeorivers and settled it northward along the coast of the young Atlantic Ocean (during the Albian). A parallel between Albian clastic deposits and the modern sediments deposited by the Benguela current is drawn, focusing on the striking resemblance between the two currents, i.e. the actual Benguela current and the Albian marine current, and the associated sedimentary bodies.
Synthèse préliminaire des travaux menés sur le bassin de Benguela (Sud Angola) : implications sédimentologiques, paléontologiques et structurales.
12 pages; International audience; Les travaux menés dans le bassin de Benguela ont apporté une moisson de nouvelles données de terrain quant à la période apto-albienne de ce secteur ouest africain. Outre les résultats majeurs obtenus en ce qui concerne les faunes d'ammonites jusqu'alors peu étudiées dans ce bassin, et qui ont permis des corrélations indispensables pour la compréhension du fonctionnement de la sédimentation, cette étude a permis de mettre en évidence une compartimentation remarquable de la sédimentation et des structures de tectonique salifère. Des tels résultats ont une portée à la fois fondamentale et appliquée. En effet, il paraît que le bassin de Benguela soit un des rar…