1980 - National Institute of Oceanography

ecords in 13 other bays showed the thickness of the sand to be about 21 metres.
Thus, the total reserves of ilmenite in these bays appear to be many times greater
than that of the Ratnagiri Bay.
• A study of the sediments of the region surrounding Cape Comorin showed
that its western side is dominated by terrigenous sediments while its eastern side
is dominated by carbonate sediments.
• X-ray diffraction studies on limestone dredge from the shelf (90 m. depth)
showed that its mineralogy does not indicate its exposure to fresh water resulting
either from rainfall or from percolation of ground water. These results support
earlier findings that the Peninsular India had a semi-arid climate in the past.
• Studies on the crustal structure and basement tectonics of the Bay of Bengal
have delineated several new surface and subsurface structural features such as an
escarpment as a surface and a subsurface high over the continental slope extending
along the east coast, a deep and wide marginal basin over the southern continental
margin and graben extending in southeast and northeast directions.
• Experiments on raft-grown mussels showed that the cultured mussels develop
special behavioural, physiological and bio-chemical adaptations to overcome the
range of variation in the environmental factors at the culture site. Growth studies
on the shrimps Penaeus indicus and Metapenaeus dobsoni under different frequency
of feeding revealed that growth patterns in both tne species follow a linear trend.
• A system was designed in the laboratory to simulate the field conditions for
the study of the role of microorganisms in specialized ecosystem like mangroves.
• Memodyne digital cassette recorder interfacing circuits have been developed
for temporary storage of oceanographic data.
• A single board computer-based microprocessor was designed and developed.
A serial monitor programme was also developed to communicate with the microprocessor
through a teletype or an RS-232-D terminal.
• The design and fabrication of an indigenous CTD system, shallow water echosounder
and a profile current meter were completed.
• The design of a laboratory model of OTEC plant of capacity 200 watts was
completed.
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