Journal of Geological Society of India (Online archive from Vol 1 to Vol 78)

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Structural Study of Meghalaya Plateau Through Aeromagnetic Data


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1 RSAS, Geological Survey of India, Vasudha Bhavan, K.S. Layout, Bangalore – 560 078, India
     

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The study of aeromagnetic data over parts of Assam-Meghalaya has delineated major discontinuities representing faults/fractures/contacts/shears and magnetic body axes, which helped in understanding the regional and structural setup of the area. The known Barapani and Dapsi Thrusts, Dudhnai Fault and three strong magnetic anomalies with reverse magnetisation have been delineated. The quantitative analysis of aeromagnetic data brought out the depths of magnetic interfaces and the magnetic picture of different layers, which also helped in understanding the regional and structural setup. The contact modeling across few profile sections showed the depths to the top of contacts and the map of magnetic-basement-depth-model revealed the undulations of the basement. Magnetic body axes of several magnetic anomalies and also several magnetic discontinuities representative of faults/ fractures/ contacts/ shears system in the area along with five potential blocks for mineral prospecting are the main outcome of this exercise. The seismotectonic activity associated with the magnetic features has also been studied to understand the structural setup.

Keywords

Structural Study, Aeromagnetic Data, Meghalaya.
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  • Structural Study of Meghalaya Plateau Through Aeromagnetic Data

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Authors

Rajendra Sharma
RSAS, Geological Survey of India, Vasudha Bhavan, K.S. Layout, Bangalore – 560 078, India
H. C. Gouda
RSAS, Geological Survey of India, Vasudha Bhavan, K.S. Layout, Bangalore – 560 078, India
R. K. Singh
RSAS, Geological Survey of India, Vasudha Bhavan, K.S. Layout, Bangalore – 560 078, India
B. V. Nagaraju
RSAS, Geological Survey of India, Vasudha Bhavan, K.S. Layout, Bangalore – 560 078, India

Abstract


The study of aeromagnetic data over parts of Assam-Meghalaya has delineated major discontinuities representing faults/fractures/contacts/shears and magnetic body axes, which helped in understanding the regional and structural setup of the area. The known Barapani and Dapsi Thrusts, Dudhnai Fault and three strong magnetic anomalies with reverse magnetisation have been delineated. The quantitative analysis of aeromagnetic data brought out the depths of magnetic interfaces and the magnetic picture of different layers, which also helped in understanding the regional and structural setup. The contact modeling across few profile sections showed the depths to the top of contacts and the map of magnetic-basement-depth-model revealed the undulations of the basement. Magnetic body axes of several magnetic anomalies and also several magnetic discontinuities representative of faults/ fractures/ contacts/ shears system in the area along with five potential blocks for mineral prospecting are the main outcome of this exercise. The seismotectonic activity associated with the magnetic features has also been studied to understand the structural setup.

Keywords


Structural Study, Aeromagnetic Data, Meghalaya.

References