Geochemistry of manganese nodules from the N.W. Indian Ocean

Manganese nodules collected from four sites in the N.W. Indian Ocean by R.R.S. Discovery have been analysed for a range of elements. At two of the sites, samples were collected from two morphological populations, at one of these sites each population being a distinct chemical population also. In addition, considerable differences have been observed in the composition of morphologically similar modules from sites a few miles apart. The information obtained is of significance in any consideration of the genesis of the nodules and could have practical implications in the event that manganese nodules become a potential source of manganese and other metallic elements.