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The Canary Islands developed in a geodynamic setting characterized by old (Jurassic) oceanic lithosphere lying close to a passive continental margin, and on a very slow-moving tectonic plate (the African plate). The absolute easterly motion of the African plate over fixed hotspots has been estimated (O’Connor & Duncan 1990) for the Walvis Ridge at c. 7 in latitude and 34 in longitude for the last 60 Ma. In the region of the Canaries these values may be as low as 2.4 and 5 (c. 9 mm/year), respectively, for this period. Another potentially very important difference between the Canaries and most other oceanic island groups is that the Canaries are located adjacent to a region of intense active deformation, comprising the Atlas and Rif mountains, Alboran sea and Betic Cordillera provinces of the alpine orogenic belt. Some authors postulate the extension to the Canaries of an offshore branch of the trans-Agadir fault, associated with the Atlas system (Anguita & Hernán 1975, 1986, 2000), although there is no obvious geological or geophysical evidence for this (eg Dillon & Sougy 1974). Neither the Canarian archipelago as a whole, nor the individual islands and their volcanic centres and rifts follow the postulated extension of the Atlas fault to the Canaries. In fact, the islands of Fuerteventura and Lanzarote are parallel to the continental margin, whereas most of the remaining islands of the archipelago follow a general east–west trend, and the dual line of La Palma and El Hierro forms a north–south trend. Rifts in the western islands are radial and do not relate to the Atlas trend (Carracedo 1994). Rihm et al.(1998) demonstrate the presence of a group of …