Magnetic anomalies in the northeast Atlantic between the Canary and Cape Verde Islands

During 1968 about 7500 km of new magnetic data Were recorded by the USNS J. W. Gibbs between the Canary and Cape Verde islands, from the continental shelf to approximately 30°W. These data, together with an equal amount of data from other sources, reveal major magnetic features. The magnetic boundary between relatively undisturbed and disturbed magnetic zones is delineated near the middle of the northwest African continental rise. A sequence of linear north-south-trending anomalies immediately seaward of the magnetic boundary comprise a band about 300 km wide and can be correlated from about 15°N at the Cape Verde Islands to about 26°N just south of the Canary Islands. The band of magnetic anomalies appears to have a right lateral offset of about 100 km near 25°N where intersected by a west-northwest-trending fault near the eastward projection of the Atlantis fracture zone from the mid-Atlantic ridge. At least one prominent positive magnetic anomaly is associated with the northwest, African continental shelf. The magnetic disturbance boundary and the associated band of linear magnetic anomalies are nearly mirror images of similar anomalies associated with the continental margin off eastern North America.