Ferromanganese nodules rates

Krishnaswami S. and Cochran J. K. (1978) Uranium and thorium series nuclides in oriented ferromanganese nodules growth rates, turnover times and nuclide behavior. Earth Planet. Sci. Lett. 40, 45-62. 

Ferromanganese nodules are primarily centimeter-sized concretions of iron and manganese oxide. They occur on the deep seafloor where pelagic sediment accumulation rates are slow... 

Dean, W.E., Ghosh, S.K., Krishnaswami, S. and Moore, W.S., 1973. Geochemistry and accretion rates of freshwater ferromanganese nodules. In M. Morgenstein (Editor), The Origin and Distribution of Manganese Nodules in the Pacific and Prospects for Exploration. Hawaii Institute of Geophysics, pp. 13—20. 

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