A detailed aeromagnetic survey centered on the Mid-Atlantic Ridge was processed by using a new algorithm to reduce navigational errors. Small areas within the survey were selected for multidirectional stacking to reduce noise and determine best-fitting azimuths. This analysis allowed identification of sea floor spreading anomalies out to anomaly 9. Anomaly azimuths indicate two periods of oblique spreading with a left lateral sense: from 25 to 14 m.y. ago and from 9 m.y. ago to the present. Oblique spreading may have resulted from locking of transform faults each time the African plate begin to spread in a more northerly direction away fromn the American plate. |