Linking the Canary and Cape-Verde Hot-Spots, Northwest Africa

摘要

The Canary and Cape-Verde archipelagos are two groups of volcanic islands often cited as case examples of the surface expression of two distinct hot-spot plumes. However, several considerations that␣we enumerate suggest a link between the two archipelagos. Using seismic profiles we describe a continuous morphological basement ridge that exists between the two archipelagos. We then examine the stratigraphic record available from field data on Fuerteventura Island (Canary) and Maio Island (Cape-Verde) and from a few Deep Sea Drilling Project (DSDP) holes. The geological history of these volcanic islands is very similar since the formation of their oceanic basement during the Late Jurassic. They share the same and synchronious sedimentary evolution (subsidence, uplift and emersion) as well as very similar timing of volcanism and deformation. The two distinct hot-spots model does not appear adapted to account for the formation of these structures as it ignores the existence of the ridge, as well as most of the geological coincidences. By describing the coinciding geological incidents, we argue that it is misleading to treat these two regions apart.