SEDIMENTS AND MARINE MINERAL-RESOURCES IN THE EASTERN INDIAN-OCEAN

Sedimentation regimes are an important control on the distribution of marine mineral resources worldwide. In the eastern Indian Ocean, phosp horites are associated with organic-rich sediments including coral ree fs on continental margin areas, principally off western India, and pos sibly occur on seamounts throughout the equatorial and subequatorial p arts of the region. Metalliferous sediments and polymetallic sulfides can be expected to be located in areas of volcaniclastic and hydrother mal sedimentation in and near the Indonesian Island arcs and on the mi d-ocean ridge system, the Southeast Indian Ridge. Manganese nodules ar e both abundant and high grade in the central Indian Basin in associat ion with slowly accumulating manganese-rich pelagic clays, and sedimen t data suggest that a similar situation may prevail in the Wharton Bas in.