A revised paleo-reconstruction of the Equatorial Atlantic from new magnetic, gravity, and seismic reflection data, offshore Guinea

The Guinea margin, situated within the Equatorial Atlantic represents the final point of separation between Africa and South America during Triassic to Cretaceous rifting to form the North and South Atlantic. Despite being in such a tectonically interesting region, relatively little data have been published about the Guinean continental margin. Consequently, prior plate reconstructions within the Equatorial Atlantic lack sufficient detail to provide a fully reasonable explanation for the complex rift structure observed within new 2-D and 3-D seismic datasets. New observations drawn from the seismic data, and local gravity and magnetic data, permit development of a new paleoreconstruction model across the Guinea Plateau. Furthermore, using magnetic reversals, fracture zones have been extended farther towards the continental margin. This has provided further accuracy and constraint of plate motions, and suggests a greater north-south extensional component is required during initial rifting. These revised plate motions and their timings have provided information on fault kinematics that are observed within the 3-D seismic data, facilitating a more accurate basin development framework. The creation of this more-detailed Equatorial Atlantic plate reconstruction not only aids in better understanding of rift evolution, but presents opportunities for increased insight into how global oceanic circulation patterns and climate change are affected by tectonic activity.