Schematic Map of Boundary Between Eurasian and African Plates
Boundary between the Eurasian and African plates. Both plates are moving eastward, but the African plate is also rotating counterclockwise around a point a short distance west of the coast of Africa. As a result, there is a crustal extension, hence fracturing and volcanism, in the Azores Islands. Offshore from Lisbon, compression of the crust has led to uplifting of the ocean floor in places. Courtesy of Jelle de Boer/Princeton University Press)