Abstract
The Andaman Islands form part of the outer-arc accretionary sedimentary complex belonging to the Andaman–Sumatra active subduction zone. The islands are characterized by thick cover of Neogene sediments along with exposed ophiolite rocks at few places. A regional magnetic survey was carried out for the first time over the Andaman Islands with a view to understand the correlation of anomaly signatures with surface geology of the islands. The residual total field magnetic anomaly maps have revealed distinct magnetic anomalies having intermediate to high amplitude magnetic signatures and correlate with the areas over/close to the exposed ophiolite rocks along the east coast of north, middle and the south Andaman Islands. The 2D modelling of magnetic anomalies along selected E–W profiles across the islands indicate that the ophiolite bodies extend to a depth of about 5–8 km and spatially correlate with the mapped fault/thrust zones.
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References
Acharyya S K 2007 Collisional emplacement history of the Naga–Andaman ophiolites and the position of the eastern Indian suture; J. Asian Earth Sci. 29 229–242.
Bandopadhyay P C 2005 Discovery of abundant pyroclasts in the Namunagarh Grit, south Andaman: Evidence for the arc volcanism and active subduction during the Paleogene in the Andaman Sea; J. Asian Earth Sci. 25 95–107.
Chatterjee P K 1967 Geology of the main islands of the Andaman area; Proc. Symp. Upper Mantle Project, Hyderabad, India, pp. 348–362.
Cochran J R 2010 Morphology and tectonics of the Andaman Forearc, northeastern Indian Ocean; Geophys. J. Int. 182 631–651.
Curray J R, Emmel F J, Moore D G and Raitt R W 1982 Structure, tectonics and geological history of the northeastern Indian Ocean; In: The Ocean Basins and Margins (eds) Nairn A E M and Stehli F G (New York: Plenum), 6 399–450.
Curray J R 2005 Tectonics and history of the Andaman Sea region; J. Asian Earth Sci. 25 187–232.
Dhana Raju R and Negi B S 1984 Petrography and tectonic setting of the Andaman ophiolite suite with a note on its evolution; J. Geol. Soc. India 25 655–665.
Eremenko N A and Sastri V V 1977 On the petroleum geology of Andaman Islands; Bull. ONGC India 14 1–13.
Gahalaut V K, Jade S, Catherine J K, Gireesh R, Ananda M B, Dileep Kumar P, Narsiah M, Jafri S H, Ambikapathy, A, Bansal A, Chadha R K, Gupta D C, Nagarajan B and Kumar S 2008 GPS measurements of post-seismic deformation in the Andaman–Nicobar region following the giant 2004 Sumatra–Andaman earthquake; J. Geophys. Res. 113 B08401—08418.
Ghosh B, Morishita T and Bhatta K 2013 Significance of chromian spinels from the mantle sequence of the Andaman ophiolite, India: Paleogeodynamic implications; Lithos 164–167 86–96.
Gokarn S G, Gupta G, Dutta S and Hazarika N 2006 Geoelectric structure in the Andaman Islands using magnetotelluric studies; Earth Planet. Space 58 259–264.
Hamilton W 1979 Tectonics of the Indonesian region; U.S.G.S Prof. Paper 1078 345.
Jafri S M and Sheikh J M 2013 Geochemistry of pillow basalts from Bompoka, Andaman–Nicobar islands, Bay of Bengal, India; J. Asian Earth Sci. 64 27–37.
Jafri S H, Sarma D S and Sheikh J M 2010 Hyaloclastites in pillow basalts, south Andaman Island, Bay of Bengal, India; Curr. Sci. 99 1825–1828.
Jarvis A, Reuter H I, Nelson A and Guevara E 2008 Hole-filled SRTM for the globe Version 4, available from the CGIAR-CSI SRTM 90m Database: http://srtm.csi.cgiar.org.
Kamesh Raju K A, Ramprasad T, Rao P S, Ramalingeswara Rao B and Varghese J 2004 New insights into the tectonic evolution of the Andaman basin, northeast Indian Ocean; Earth Planet. Sci. Lett. 221 145–162.
Klootwijk C T, Gee J S, Peirce W and Smith G M 1991 Constraints on the India-Asia convergence: Paleomagnetic results from Ninetyeast Ridge; Proc. Ocean Drilling Program, Scientific Results 121 771–882.
Mukhopadhyay M 1984 Seismotectonics of subduction and back arc rifting under the Andaman Sea; Tectonophys. 108 229–239.
Mukhopadhyay B, Chakraborty P P and Paul S 2003 Facies clustering in turbidite successions: Case study from Andaman Flysch Group, Andaman Islands, India; Gondwana Res. 6 918–924.
Narayana A C 2011 Tectonic geomorphology, tsunamis and environmental hazards: Reference to Andaman–Nicobar Islands; Nat. Hazards 57 65–82.
Pal T, Chakraborty P P, Gupta T D and Singh C D 2003a Geodynamical evolution of the outer-arc–forearc belt in the Andaman Islands, the central part of the Burma and Java subduction complex; Geol. Mag. 140 289–307.
Pal T, Chakraborty P P and Gosh R N 2003b PGE distribution in chromite placers from Andaman ophiolite and its boninitic parentage; J. Geol. Soc. India 62 671–680.
Pal T 2011 Petrology and geochemistry of the Andaman ophiolite: Melt–rock interaction in a suprasubduction-zone setting; J. Geol. Soc. London 168 1031–1045.
Pandey J, Agarwal P P, Dave A, Maithani A, Trivedi K B, Srivastava A K and Singh D N 1992 Geology of Andaman; Bull. ONGC India 29 19–103.
Radhakrishna M, Lasitha S and Mukhopadhyay M 2008 Seismicity, gravity anomalies and lithospheric structure of the Andaman arc, NE Indian Ocean; Tectonophys. 460 248–262.
Radhakrishna T 2003 Modeling of lithospheric evolution using geophysical method: The evidenece from Paleomagnetic studies; Geol. Soc. India Memoir 53 247– 278.
Radhakrishna T and Mathew J 2012 Geochemistry and paleomagnetism of late Cretaceous mafic dykes in Kerala, southwest coast of India in relation to large igneous provinces and mantle plumes in the Indian Ocean region; Geol. Soc. Am. Bull. 124 240–255.
Ray K K 1985 East coast volcanics – A new suite in the ophiolite of Andaman Islands; Rec. Geol. Surv. India 116 83–87.
Ray K K, Sengupta S and Van Den Hul H J 1988 Chemical characteristics of volcanic rocks from Andaman ophiolite, India; J. Geol. Soc. London 145 393–400.
Rodolfo K S 1969 Bathymetry and marine geology of the Andaman basin, and tectonic implications for southeast Asia; Geol. Soc. Am. Bull. 80 1203–1230.
Roy D K, Acharyya S K, Ray K K, Lahiri T C and Sen M K 1988 Nature of occurrence and depositional environment of the oceanic pelagic sediments associated with the ophiolite assemblage, South Andaman Island; Indian Minerology 42 31–56.
Roy S K 1992 Accretionary prism in Andaman Forearc; Geol. Surv. India Spec. Publ. 29 273–278.
Roy S K and Das Sharma S 1993 Evolution of Andaman forearc basin and its hydrocarbon potential; Proc. 2nd Seminar on Petroliferous basins of India 1 409–435.
Roy T K 1983 Geology and hydrocarbon prospects of Andaman–Nicobar Basin; Petroleum Asia J. 1 37–50.
Rukstales K S and Love J J 2007 The International Geomagnetic Reference Field, 2005: U.S. Geological Survey Scientific Investigations Map 2964, 5 pls., scale 1:30,000,000.
Sarma D S, Jafri S H, Fletcher I A and McNaughton N J 2010 Constraints on the tectonic setting of the Andaman ophiolites, Bay of Bengal, India, from SHRIMP U–Pb Zircon geochronology of plagiogranite; J. Geol. 118 691–697.
Sengupta S, Ray K K, Acharyya S K and de Smeth J B 1990 Nature of ophiolite occurrences along the eastern margin of the Indian plate and their tectonic significance; Geology 18 439–442.
Srivastava R K, Chandra R and Shastry A 2004 High-Ti type N-MORB parentage of basalts from the south Andaman ophiolite suite, India; Proc. Indian Acad. Sci. (Earth Planet. Sci.) 113 605–618.
Subba Rao P B V 2011 Frequency characteristics of geomagnetic induction anomalies in Andaman Islands; Geol. Soc. India Memoir 77 531–547.
Talwani 1965 Computation with the help of a digital computer of magnetic anomalies caused by bodies of arbitrary shape; Geophysics 30 (5) 797–817.
Weeks L A, Harbison R N and Peter G 1967 Island arc system in the Andaman Sea; Am. Assoc. Petrol. Geol. Bull. 51 1803–1815.
Acknowledgements
The authors are grateful to the Department of Science and Technology (DST), New Delhi for the financial support under the research project (ESS/16/346/2008) sanctioned to Prof. M Radhakrishna, IIT Bombay. They also thank Mr. Rishikesh, Mr. Rajubabu and the officers of the DST, Andaman & Nicobar Administration, for the excellent logistic support. Critical comments from two anonymous reviewers helped to improve the manuscript.
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SUBBA RAO, P.B.V., RADHAKRISHNA, M., HARIPRIYA, K. et al. Magnetic anomalies over the Andaman Islands and their geological significance. J Earth Syst Sci 125, 359–368 (2016). https://doi.org/10.1007/s12040-016-0660-7
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DOI: https://doi.org/10.1007/s12040-016-0660-7