Sediment distribution on the mid-ocean ridges with respect to spreading of the sea floor.

An abrupt change in sediment thickness between the crests and flanks of the mid-ocean ridges can be interpreted as a major discontinuity in the rates either of spreading of the sea floor or of accumulation of sediment. The preferable interpretation of the data is that the process of spreadig of the sea floor is intermittent and that the present cycle of spreading commenced around 10 million years ago. following a long period Of quiescence during which most of the observed sediments were deposited.