Thesignificance of time scale for the rate of accretion of marine manganese nodules and crusts

Rates of accretion published for shallow-marine manganese deposits are generally faster than those of abyssal nodules, but they are also determined for shorter time intervals. The time scale of measurement may influence the measured rates of accretion more than water depth. A single model of episodic accretion can account for measured growth rates of both shallow-water and abyssal ferromanganese accretions.