Ksr. Murthy et al., MARINE MAGNETIC-ANOMALIES AS A LINK BETWEEN THE GRANULITE BELTS OF EAST-COAST OF INDIA AND ENDERBY LAND OF ANTARCTICA, Journal of the Geological Society of India, 49(2), 1997, pp. 153-158
Magnetic data of the eastern continental margin of India (ECMI) helped
in demarcating the offshore extension of the granulite belts of east
coast of India and their possible link to those of the East Antarctica
. Short wavelength and high amplitude negative magnetic anomalies (200
to 1600 nT) are observed over the northern part of ECMI between Kakin
ada and Chilka lake and also off Madras shelf, the coastal regions of
which are associated with granulite facies rocks. This part of the she
lf is associated with structural lineaments with predominant NE-SW tre
nds. In contrast, the offshore basins off Cauvery, Krishna - Godavari
(K-G) and Mahanadi rivers are associated with subdued positive anomali
es (less than 200 nT) indicating subsidence off these basins by heavy
load of Phanerozoic/younger shelf sediments. Structural lineaments wit
h NW-SE or W-E trends delineated over these basins are related to the
offshore extension of these rift related Gondwana grabens. Similarity
in the trends of the magnetic anomalies and the granulite facies on th
e east coast of India and their correlation with the granulite belt of
Enderby Land of Antarctica supports the view that the entire region c
omprised of a single and stable block of granulite rocks prior to the
fragmentation of the Gondwanaland. The study also suggests probable co
ntinuation of Mahanadi and Godavari grabens into East Antarctica.