Abstract
Marine magnetic anomalies along three representative profiles falling between shelf break and continent–ocean boundary in the offshore Krishna–Godavari basin were quantitatively interpreted for understanding the nature and structure of the magnetic basement using inversion technique. The interpretation of the anomalies shows that the magnetic basement lies deeper than the base of the sediments, i.e., acoustic basement identified by the seismic studies. This interpretation also shows that the magnetic basement is faulted along the NW–SE direction with the upthrown side lying to the north of the anomaly trend of this region. The coincidence of magnetizations observed through the present interpretation with that of charnockites of neighbouring EGMB and onshore K–G basin areas indicates that EGMB geology (charnockites, granitic gneiss, etc.) extends up to COB in the offshore K–G basin.
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Acknowledgements
Authors are grateful to Dr S W A Naqvi, Director, NIO (CSIR), Goa and to Dr V S N Murty, Scientist-in-Charge, Regional Centre, NIO, Visakhapatnam, India, for their encouragement. The authors are also thankful to Prof. I V Radhakrishna Murthy for his valuable suggestions to improve the manuscript. The first author Dr. V Subrahmanyam is grateful to CSIR, New Delhi for grant of Emeritus Fellowship under which this work was carried out. Neetha Raj is thankful to Dept. of Science & Technology, New Delhi for granting the Junior Research Fellowship through Inspire Programme. This is NIO (CSIR) contribution no. 7132.
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SUBRAHMANYAM, V., SWAMY, K.V. & RAJ, N. Basement configuration of KG offshore basin from magnetic anomalies. J Earth Syst Sci 125, 663–668 (2016). https://doi.org/10.1007/s12040-016-0672-3
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DOI: https://doi.org/10.1007/s12040-016-0672-3