Seismicity along divergent plate boundaries is concentrated along the crest of the mid-ocean ridge the lowest parts of the oceanic crust rocky areas away from the rift zones

Seismicity along divergent plate boundaries is concentrated along rocky areas away from the rift zones. 
An oceanic ridge marks divergent plate boundaries in the ocean basins. It is broad, fractured swell with a total length of 70,000 km. Basaltic volcanism and shallow earth quakes are concentrated along the rift zone at the ridge crest. The ridge's characteristics depend upon the spreading rate. 

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