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Trap thickness and the subtrappean structures related to mode of eruption in the Deccan Plateau of India: results from magnetotellurics


Deccan trap thickness is an important parameter in understanding the eruption process of flood basalts (65 My). A magnetotelluric study was carried out in Deccan Volcanic Province (DVP) of the Indian Peninsular shield during 1998–1999. Modeling results clearly revealed variations both in the thickness of the Deccan traps and in their resistivity from the west coast to the eastern boundary of DVP. The thickness of the traps in DVP decreases from about 1.8 km in the west to a few hundred meters (approx. 400 m) towards the east. The traps also exhibit considerable variation in resistivity, with higher resistivities (approx. 150–200 ohm-m) in the western half and lower resistivities (approx. 50–100 ohm-m) in the eastern half of DVP. Two significant fissure/fracture zones have been detected in DVP; these may have acted as conduits for the outpouring of Deccan lavas in addition to the primary structures along the west coast and the Narmada-Son lineament (NSL) zones.


  1. Allegre, C. J., J. L. Birck, Capmas, F. and V. Courtillot, Age of the Deccan Traps using 187Re-187Os systematics, Earth Planet. Sci. Lett., 170, 197–204, 1999.

  2. Baksi, A. K., Geochronological studies on whole-rock basalts, Deccan traps, India: evaluation of the timing of volcanism relative to the K-T boundary, Earth Planet. Sci. Lett., 121, 43–56, 1994.

  3. Beane, J. E., C. A. Turner, P. R. Hooper, K. V. Subbarao, and J. N. Walsh, Stratigraphy, composition and form of Deccan Basalts, Western Ghats, India. Bull. Volcanol., 48, 61–83, 1986.

  4. Berdichevsky, M. N. and V. I. Dmitriev, Basic principles of interpretation of magnetotelluric sounding curves, in Geoelectric and Geothermal Studies, pp. 165–221, edited by A. Adam, KAPG Geophysics Monographs, Akademiai Kiado, Budapest, 1976.

  5. Biswas, S. K., Rift basins in western margin of India and their hydrocarbon prospects with special reference to Kutch basin, Am. Assoc. Petr. Geol. Bull., 66, 1497–1513, 1982.

  6. Biswas, S. K., Regional tectonic framework, structure and evolution of the western marginal basins of India, Tectonophysics, 135, 307–327, 1987.

  7. Bodas, M. S., S. F. R. Khadri, and K. V. Subbarao, Stratigraphy of the Jawahar and Igatpuri formations, Western Deccan Province, in Deccan Flood Basalts,edited by K. V. Subbarao, Mem. Geol. Soc. India, 10, 235–252, 1988.

  8. Crumansonata, Geoscientific studies of the Son-Narmada-Tapti Lineament zone, Geological Society of India, Special Publication 10, 371, 1995.

  9. Courtillot, V., J. Besse, D. Vandamme, T. Montigny, J. J. Jaeger, and H. Cappetta, Deccan flood basalts at the Cretaceous/Tertiary boundary?, Earth Planet. Sci. Lett., 80, 361–374, 1986.

  10. Courtillot, V., G. Féraud, H. Maluski, D. Vandamme, M. G. Moreau, and J. Besse, Deccan flood basalts and the Cretaceous/Tertiary boundary, Nature, 333, 843–846, 1988.

  11. Duncan, R. A. and D. G. Pyle, Raid eruption of the Deccan Traps at the Cretaceous/Tertiary boundary, Nature, 333, 841–843, 1988.

  12. Gokarn, S. G., C. K. Rao, B. P. Singh, and P. N. Nayak,. Magnetotelluric studies across the Kurduwadi gravity feature, Phys. Earth Planet. Int., 72, 58–67, 1992.

  13. Kaila, K. L., K. Roy Chowdhury, P. R. Reddy, V. G. Krishna, Hari Narain, S. I. Subbotin, V. B. Sollogub, A. V. Chekunov, G. E. Kharetchko, M. A. Lazarenko, and T. V. Ilchenko, Crustal structure along Kavali-Udipi profile in the Indian Peninsular Shield from deep seismic soundings, J. Geol. Soc. India, 10, 307–333, 1979.

  14. Kaila, K. L., P. R. Reddy, M. M. Dixit, and M. A. Lazrenko, Deep crustal structure at Koyna, Maharashtra indicated by Deep Seismic Soundings, J. Geol. Soc. India, 22, 1–16, 1981a.

  15. Kaila, K. L., P. R. K. Murty, V. K. Rao, and G. Kharetchko, Crustal structure from deep seismic sounding along the KOYII (Kelsi-Loni) profile in the Deccan trap area, India, Tectonophysics, 73, 365–384, 1981b.

  16. Kailasam, L. N., Plateau uplift in Peninsular India, Tectonophysics, 61, 243–269, 1979.

  17. Krishna Brahmam, N. and J. G. Negi, Rift valleys beneath the Deccan trap (India), Geophys. Res. Bull., 11, 207–237, 1973.

  18. Mahadevan, T. M. and K. V. Subbarao, Seismicity of the Deccan Volcanic Province-An evaluation of some endogenous factors, Mem. Geol. Soc. India, 43, 453–484, 1999.

  19. Mitchell, C. and M. Widdowson, A geological map of the southern Deccan traps, India and its structural implications, J. Geol. Soc. London, 148, 495–505, 1991.

  20. Morgan, W. J., Hotspot tracks and the opening of the Atlantic and Indian Oceans, in The Sea, edited by C. Emiliani, Vol. 7, pp. 443–487, John Wiley, New York, 1981.

  21. Negi, J. G., P. K. Agrawal, and K. N. N. Rao, Three-dimensional model of the Koyna area of Maharashtra state (India) based on the spectral analysis of aeromagnetic data, Geophysics, 48, 964–974, 1983.

  22. Patro, B. P. K., H. Brasse, S. V. S. Sarma, and T. Harinarayana, Electrical structure of the crust below the Deccan Flood Basalts (India), inferred from magnetotelluric soundings, Geophys. J. Int., 163, 931–943, 2005a.

  23. Patro, B. P. K., T. Harinarayana, R. S. Sastry, M. Rao, C. Manoj, K. Naganjaneyulu, and S. V. S. Sarma, Electrical imaging of Narmada-Son Lineament Zone, Central India from magnetotellurics, Phys. Earth Planet. Inter, 148, 215–232, 2005b.

  24. Peng, Z, X., J. Mahoney, P. Hooper, C. Harris, and J. Beane, A role for lower continental crust in flood basalt genesis? Isotopic and incompatible element study of the lower six formations of the western Deccan Traps, Geochim. Cosmochim. Acta, 58, 267–288.

  25. Radhakrishna, B. P., An excursion into the past-„The Deccan volcanic episode”, Curr. Sci., 61, Nos 9/10, 641–647, 1991.

  26. Radhakrishna, B. P., Neogene uplift and geomorphic rejuvenation of the Indian peninsula, Curr. Sci., 64, Nos. 11/12, 787–793, 1993.

  27. Ranganayaki, R. P., An interpretive analysis of magnetotelluric data, Geophysics, 49, 1730–1748, 1984.

  28. Ray, S., Petrologic evolution of the Deccan traps, Sci. Cult., 33, 252–256, 1967.

  29. Sarma, S.V.S. etal., Magnetotellurics studies, (in) Integrated Geophysical Studies For Hydrocarbon Exploration Saurashtra, India, NGRI Technical Report No: NGRI-98-EXP-237, pp. 181–262, 1998.

  30. Sen, G., Generation of Deccan Trap magmas, Proc. Indian Acta. Sci (Earth Planet. Sci.), 110, 409–431, 2001.

  31. Smith, T., M. Hoversten, E. Gasperikova, and F. Morrison, Sharp boundary inversion of 2D magnetotelluric data, Geophys. Prospect., 47, 469–486, 1999.

  32. Subbarao, K. V., C. Mitchell, and M. Widdowson, Latur continental earthquake from the southeastern Deccan Basalt Province, India. Abstract. IUGG Meeting 1995. Section of SW7 Intracontinental Earthquakes, 1995.

  33. Subbarao, K. V. and P. R. Hooper, Reconnaissance map of the Deccan basalt group in Western Ghats, India, in Deccan Flood Basalts, edited by K. V. Subbarao, Mem. Geol. Soc. India, No. 10, 1988.

  34. Subbarao, K. V., D. Chandrasekharam, P. Navaneethakrishnan, and P. R. Hooper, Stratigraphy and structure of parts of the central Deccan Basalt province: Eruptive models, in Volcanism, edited by K. V. Subbarao, Wiley Eastern Ltd., pp. 321–332, 1994.

  35. Subbarao, D. V., Zero-free air-based gravity anomaly (preliminary) map of South India-A refined and redefined Bouguermap, Curr. Sci., 82, No. 11, 2002.

  36. Tiwari, V. M., M. B. S. Vyaghraswara Rao, and D. C. Mishra, Density inhomogeneties beneath Deccan volcanic province, India, as derived from gravity data, J. Geodyn., 31, 1–17, 2001.

  37. West, W. D., The Deccan Trap and Other Flood Eruptions-a comparative study, Mem. Geol. Soc. India, 43, 129–144, 1999.

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Patro, B.P.K., Sarma, S.V.S. Trap thickness and the subtrappean structures related to mode of eruption in the Deccan Plateau of India: results from magnetotellurics. Earth Planet Sp 59, 75–81 (2007).

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Key words

  • Deccan traps
  • resistivity
  • magnetotellurics
  • fissures