Ocean floor spreading: olduvai and gilsa events in the matuyama epoch

The magnetic anomaly usually associated with the Olduvai geomagnetic event (1.96 million years) should probably be associated with the Gilsa event (~ 1.65 million years). The Oldu-vai event can be correlated with a con-sistently appearing minor anomalycalled W. This reassignment gives near-ly uniform spreading rates for sections of the mid-ocean ridge system consid-ere( l here.