『Abstract
The ferromanganese nodule resources of the Indian Ocean Nodule
Field (IONF) are second only in the world in terms of metal content
and abundance. Since it was made known by Mero (1965) that several
trillion tonnes of manganese nodules lay in the world oceans,
extensive exploration for nodules has been undertaken during the
last four decades. The possibility of harvesting an inexhaustible
supply of nodules from oceans has resulted in formulation of several
national and international programs. India started her search
for ferromanganese nodules in 1982.
The investigations have resulted in a comprehensive assessment
of manganese nodule resources at the ocean-level, and on inter-basin
model for nodule growth, albeit with several inaccuracies. We
list some of the essential requirements for the formation of nodules
including the availability of nucleating materials, presence of
metals in water column and sediment, favourable tectonic and physiographic
features, helpful acoustically transparent sediment-water interface,
low rate of sedimentation, presence of nutrient-rich bottom water
mass and an oxidizing environment.
We present here an integrated assessment of process of formation
of ferromanganese nodules from the IONF, which are variable even
on scale of metres. This assessment will help evaluate the metal
potential of these nodules more realistically, and the model should
bring about a predictive estimate of other nodule-bearing areas
in the world oceans.
Keywords: Ferromanganese nodules; Indian Ocean Nodule Field; Influencing
parameters; Nodule formation and dynamics; Model of nodule formation』
1. Introduction
2. Factors influencing nodule formation
3. Model of nodule formation
Acknowledgements
References