"Seamount ferromanganese crusts in northern Indian Ocean: Genesis, paleoceano-graphy, and resource potential."

Objectives:

• Locating seamount areas that are hosting cobalt-enriched ferromanganese crusts in the Indian Ocean and our EEZ
• Reconstructing past ocean physico-chemical evolution utilizing seamount ferromanganese crusts
• Exploring a metallurgical tool to extract cobalt from seamount ferromanganese crusts utilizing microbial leaching technique
• Accumulating preliminary baseline environmental data from regions of ferromanganese crust occurrences

General description: 

Most of the seamounts in the world ocean host ferromanganese crusts that have accumulated over several millions of years through oxidative colloidal precipitation of metal-hydroxides. The accumulation of these deposits is extremely slow of the order of few molecular layers per year (fem mm per million years). They are like a volume containing micron thin pages! Each page is made-up of oxides of Fe, Mn, Co, Cu, Ni, Pb, Zn etc along with REE and PGE. The bottommost page (highest page number) is the oldest to be formed. Thus the seamount ferromanganese crusts can be considered as a book of oceanpographic history read from last page towards first page (youngest). They enrich above transition metals and other rare elements several orders of magnitude more than available in seawater as dissolved constituents. Several complex chemical interactions such oxidative precipitation, surface adsorption, mechanical incorporation of exotic matter etc determine their chemical composition and mineralogy. Each these processes reflect the oceanographic conditions prevailed during the formation of each layer. Thus it is possible to trace-back the changes in ocean (Paleoceanography). The project thus aims at not only exploring for valuable mineral deposits hidden under the sea, but also attempts to understand the past oceans.

Scientific components and achievements:

• generate a 3-D multibeam bathymetric map of the entire Afanisiy-Nikitin Seamount region (trending ~400 km in NS and ~200 km in EW directions, covering seafloor area of ~80,000 sq. km.),
• sample the entire region to know the occurrence of ferromanganese crusts, and
• determine their chemical characteristics. Based on the data collected the possibility of resource grade deposits in this region will be assessed. We also plan to sample all large seamounts in the Indian waters to know the possibility of such deposits. Few oceanographic data useful to know baseline envrionmental conditions in the region will be collected during the program, in addition to carrying out various research activity in paleoceanography, paleoclimate, bioleaching etc.

Facilities available:

ICP-AES (NIO), ICP-MS (NGRI), GC-MS & IR-MS (NIO), Wet geochemistry lab, micropaleontology lab, and laboratories for biological studies are available