Annual Report 2009-2010 - Ministry Of Earth Sciences

The work carried out by NCAOR, NIO and NIOT are summarised below:
Organisation
NCAOR
Deep water
beyond 500m
Total area about
1.5 million sq km
3.1 lakh sq km
area surveyed
Shallow water
up to 500m
Total area about
0.5 million sq km
NIO - About 4000 sq km
area surveyed
NIOT - 8300 sq km area
surveyed
Area covered
- Andaman and Nicobar, Lakshadweep
off Marmagoa, off Bombay High and
off Malpe, Karnataka coasts
off Pulicat, Sri Harikota, Ennore,
Cuddalore, Kovalam, Nagapattinam
region etc.
Major findings of the survey are presented below:
i) The survey confined between Ninety east
Ridge to its west and Andaman Trench in east,
revealed the presence of a long river channel
exhibiting meandering disposed more or less
in NNW-SSE (North North West – South South
East) direction.
ii) High resolution acoustic seafloor geophysical
mapping studies, involving swath bathymetry
and shallow acoustic seismic sediment
profiling carried out in the Lakshadweep
region, revealed the presence of two seamounts
as shown in Fig. 5.3.
iii) Several mound-like features were found in the
survey area to the west of Kilthan Island.
Fig. 5.3: Site I: Seamounts off Lakshadweep
iv) The survey also provided the first detailed
description of pockmarks noticed off-Goa
continental slope (15˚34´N, 72˚50´E) of the
eastern Arabian Sea at approximately water
depth of 200m.
v) A 3D map of a submarine terrace in Mumbai
high area off Tarapur was obtained through
the multi-beam echosounding survey. Further,
a near oval shaped, extremely even (slope
1:10) Fifty-Fathom-Flat (FFF) is a prominent
topographic feature along the west coast off
Mumbai, India. This has been mapped.
vi) Gaveshani bank and another coral bank (3D
map) off the Karnataka coast have also been
mapped.
5.4 Gas Hydrates Exploration
Gas hydrates with their abundant resource
potential is emerging as a potential fuel resource.
The preliminary assessment of geological condition
and limited available seismic data suggests high
possibility of occurrence of large quantity of gas
hydrates within the EEZ of India.
The multi-channel seismic data collected by various
organisations has been evaluated and based on the
data, two promising sites of 100 km x 100 km were
identified in the Krishna-Godavari (KG) and the
Mahanadi basins for detailed survey.
Ministry of Earth Sciences : Annual Report 2009-10 29