Top: Fracture zones in the central north Atlantic Ocean. The Mid-Atlantic Ridge is not a continuous feature. The linear faults that connect the offset ridge segments are transform faults and fracture zones; these are generally perpendicular to the trend of the mid-ocean ridge. Based on the bathymetrical studies of Bruce Heezen and Marie Tharp. Bottom: Diagram showing that plate movement directions are parallel to the trends of fracture zones and transforms. Modified from Hamblin & Christiansen (1998).