Skip to main content

Advertisement

We’d like to understand how you use our websites in order to improve them. Register your interest.

Integrated modeling of EM response functions from Peninsular India and Bay of Bengal

Abstract

Existing sets of magnetovariational data from the large numbers of sites distributed across the peninsular India and those in the Bay of Bengal are reanalysed to obtain inter-site vertical and horizontal field transfer functions. Maps of induction arrows relocate the earlier reported conductive zones beneath the Palk-Strait and a regional scale anomaly in the offshore region, immediately southwest of the southern tip of Indian Peninsula, named South India Offshore Conductivity Anomaly (SIOCA). Period dependence of the induction arrows suggests that with increasing period SIOCA tends to control the induction pattern over the entire peninsula. Presentation of the horizontal transfer functions in the form of ellipses of anomalous currents helps to characterize the period and spatial behaviour of horizontal fields at seafloor sites. Integrated thin sheet modeling of the on-land and seafloor induction features suggest that the greater part of the anomalous behaviour of the horizontal fields at seafloor sites can be attributed to the shielding effects due to seawater. The weak anisotropic behaviour of the horizontal fields at selected sites can be explained in terms of the concentration of the induced currents in the sediment filled troughs on either side of the 85°E Ridge. Several lines of geophysical evidence favour the hypothesis that SIOCA, low velocity zone, low magnetization anomaly, all centered near the southern tip of the India, are the relics of the interaction of Marion Plume outburst with Indian lithosphere.

References

  1. Agarwal, A. K. and J. T. Weaver, Regional electromagnetic induction around the Indian peninsula and Sri-Lanka; a three-dimensional numerical model study using the thin sheet approximation, Phys. Earth Planet. Inter., 54, 320–331, 1989.

    Article  Google Scholar 

  2. Arora, B. R., Magnetometer array studies in India: present status, data interpretation and assessment of numerical modeling results, Proc. Indian. Acad. Sci., 99, 693–716, 1990.

    Google Scholar 

  3. Arora, B. R. and C. D. Reddy, Magnetovariational study over a seismically active area in the Deccan trap province of western India, Phys. Earth Planet. Inter., 66, 118–131, 1991.

    Article  Google Scholar 

  4. Arora, B. R., M. V. Mahashabde, and R. Kalra, Indian IEEY geomagnetic observational program and some preliminary results, Braz. J. Geophys., 11, 365–386, 1993.

    Google Scholar 

  5. Arora, B. R., G. Rawat, P. B. V. Rao, R. N. Maurya, and R. V. Iyengar, Long period magnetotelluric measurements in the Dharwar craton, South India, Joint IAGA & IASPEI Assembly, Hanoi, August 19–31, 2001.

    Google Scholar 

  6. Basu, A. R., P. R. Renne, D. K. Dasgupta, F. Teichman, and R. J. Poreda, Early and late alkali igneous pulses and a high 3He plume origin for Deccan flood basalts, Science, 261, 902–906, 1993.

    Article  Google Scholar 

  7. Beamish, D., A geomagnetic precursor to the 1979 Carlisle earthquake, Geophys. J. R. astr. Soc., 68, 531–543, 1982.

    Article  Google Scholar 

  8. Burke, K. C. A., L. Delano, J. F. Dewey, A. Edelstein, W. S. F. Kidd, K. D. Nelson, A. M. C. Sengor, and J. Strup, Rifts and structures of the world. Contract Rep. Nas 5-24094, Geophys. Branch, ESA Div., Goddard Space Flight Center, Greenbelt, Md., 238, 1978.

    Google Scholar 

  9. Curray, J. R. and T. Munasinghe, Origin of the Rajmahal Traps and the 85°E Ridge: Preliminary reconstructions of the trace of the Crozet hotspot, Geology, 19, 1237–1240, 1991.

    Article  Google Scholar 

  10. Curray, J. R., F. J. Emmel, D. J. Moore, and R. W. Raitt, Structure, tectonics and geological history of the northeastern Indian ocean, in The Ocean Basin and Marigins, 6: The Indian Ocean, edited by A. E. M. Nairn and F. G. Stehli, pp. 399–450, Plenum Press, New York, 1982.

    Google Scholar 

  11. Drury, S. A., N. B. W. Harris, R. W. Holt, S. G. J. Reeves, and R. T. Wightman, Precambrain tectonics and crustal evolution in south India, J. Geol., 92, 3–20, 1984.

    Article  Google Scholar 

  12. Duncan, R. A. and M. A. Richards, Hotspots, mantle plumes, flood basalts, and true Polar wander, Rev. Geophys., 29, 31–50, 1991.

    Article  Google Scholar 

  13. Egbert, G. D. and J. R. Booker, Robust estimation of geomagnetic transfer functions, Geophys. J. R. Astr. Soc., 87, 173–194, 1986.

    Article  Google Scholar 

  14. Fujiwara, S. and H. Toh, Geomagnetic Transfer Functions in Japan Obtained by First Order Geomagnetic Survey, J. Geomag. Geoelectr., 48, 1071–1101, 1996.

    Article  Google Scholar 

  15. GSI, Geological Map compiled by A. K. Dasgupta, A. Ghose, and K. K. Chakraborty. Published by Geological Survey of India, Calcutta, India, 1993.

  16. Heinson, G. S. and F. E. M. Lilley, An application of thin sheet electromagnetic modeling to the Taman sea, Phys. Earth Planet. Inter., 81, 231–251, 1993.

    Article  Google Scholar 

  17. Honkura, Y., N. Watanabe, Y. Kaneko, and S. Oshima, Anisotropy in electromagnetic field variations and its implication for lateral inhomogeneity of the electrical conductivity structure, Phys. Earth Planet. Inter., 53, 278–286, 1989.

    Article  Google Scholar 

  18. Joseph, E. J., R. V. Iyengar, L. A. D’Cruz, and B. P. Singh, Seafloor Geomagnetic Sounding near the 85°E Ridge in the Bay of Bengal, J. Geomag. Geoelectr., 47, 421–430, 1995.

    Article  Google Scholar 

  19. Joseph, E. J., H. Toh, H. Fujimoto, R. V. Iyengar, B. P. Singh, H. Utada, and J. Segawa, Seafloor electromagnetic induction studies in the Bay of Bengal, Marine Geophysical Res., 21, 1–21, 2000.

    Article  Google Scholar 

  20. Kennett, B. L. N. and S. Widiyantoro, A low seismic wavespeed anomaly beneath northwestern India: a seismic signature of the Deccan plume?, Earth Planet. Sci. Lett., 165, 145–155, 1999.

    Article  Google Scholar 

  21. Lawver, L. A. and C. R. Scotese, A revised reconstruction of Gondwana-land, in Gondwana 6: Structure, Tectonics, and Geophysics, edited by G. D. McKenzie, pp. 17–23, Washington, D.C., American Geophysical Union Monograph, 40, 1987.

  22. Mareschal, M., G. Vasseur, B. J. Srivastava, and R. N. Singh, Induction models of southern India and effect of offshore geology, Phys. Earth Planet. Inter., 45, 137–148, 1987.

    Article  Google Scholar 

  23. Naqvi, S. M., V. Divakar Rao, and H. Narain, The proto-continental growth of Indian shield and the antiquity of its rift valleys, Precambrain Res., 1, 338–345, 1974.

    Article  Google Scholar 

  24. Nityananda, N., A. K. Agarwal, and B. P. Singh, Induction at short period on the horizontal field variation in the peninsular India, Phys. Earth Planet. Inter., 15, 5–9, 1977.

    Article  Google Scholar 

  25. Norton, I. O. and J. G. Sclater, A model for the evolution of the Indian ocean and breakup of Gondwanaland, J. Geophys. Res., 84, 6803–6830, 1979.

    Article  Google Scholar 

  26. Peirce, J. W., The northward motion of India since the late cretaceous, Geophys. J. R. Astron. Soc., 52, 277–311, 1978.

    Article  Google Scholar 

  27. Radhakrishna, B. P. and R. Vaidyanadhan, Geology of Karnataka, Geol. Soc. India., Bangalore, India, 1997.

    Google Scholar 

  28. Rajaram, M., B. P. Singh, N. Nityananda, and A. K. Agarwal, Effect of the presence of a conducting channel between India and Sri-Lanka on the features of the Equatorial Electrojet, Geophys. J. R. Astron. Soc., 56, 127–138, 1979.

    Article  Google Scholar 

  29. Ramana, M. V., V. Subrahmanyam, A. K. Chaubey, T. Ramaprasad, K. V. L. N. S. Sarma, K. S. Krishna, M. Desa, and G. P. S. Murty, Structure and origin of the 85°E Ridge, J. Geophys. Res., 102, 17995–18012, 1997.

    Article  Google Scholar 

  30. Ramaswamy, V., A. K. Agarwal, and B. P. Singh, A three dimensional numerical model study of the electromagnetic induction around the Indian peninsula and Sri Lanka island, Phys. Earth Planet. Inter., 39, 52–61, 1985.

    Article  Google Scholar 

  31. Ramkrishnan, M., Tectonic evolution of the granulite terrains of southern India, in Continental Crust of South India, edited by B. P. Radhakrishna, Mem. Geol. Soc. India, 25, pp. 45–61, 1993.

    Google Scholar 

  32. Raval, U. and K. Veeraswamy, The radial and linear modes of interaction between mantle plume and continental lithosphere: A case study from western India, J. Geol. Soc. India, 56, 525–536, 2000.

    Google Scholar 

  33. Richards, M. A, R. A. Duncan, and U. E. Courtillot, Flood basalts and hot spot tracks: Plume heads and tails, Science, 246, 103–107, 1989.

    Article  Google Scholar 

  34. Royer, J. Y., J. W. Peirce, and J. K. Weissel, Tectonic constraints on the hotspot formation of Ninetyeast ridge, Proc. Ocean Drill. Program, Scientific results, 121, 763–776, 1991.

    Google Scholar 

  35. Schmucker, U., Anomalies of Geomagnetic variations in the southwest United States, Bull. Scripps Inst. Oceanog., 13, 165, 1970.

    Google Scholar 

  36. Simpson, F., E. Steveling, and M. Leven, The effect of the Hawaiian plume on the magnetic daily variation, Geophys. Res. Lett., 27, 1775–1778, 2000.

    Article  Google Scholar 

  37. Singh, B. P., N. Nityananda, and A. K. Agarwal, Induced magnetic variation in the Indian Peninsula, Acta Geodact. Geophys. Montanist Acad. Sci. Hung., 12, 65–72, 1977.

    Google Scholar 

  38. Singh, B. P., A. K. Agarwal, and L. Carlo, Anomalies in H at Indian equatorial stations and their effect on equatorial enhancements, J. Atmos. Terr. Phys., 44, 241–244, 1982.

    Article  Google Scholar 

  39. Singh, B. P., Mita Rajaram, and V. J. Bapat, Definition of the continent-ocean boundary of India and the surrounding oceanic regions from Magsat data, Tectonophys., 192, 145–151, 1991.

    Article  Google Scholar 

  40. Storey, B. C., The role of mantle plumes in continental breakup: case histories from Gondwanaland, Nature, 377, 301–308, 1995.

    Article  Google Scholar 

  41. Subba Rao, P. B. V., B. P. Singh, and P. B. Gawali, A geoelectrical section across the Andaman Arc Sea, Northeast Indian by using Ocean Bottom Magnetometers, J. Geol. Soc. India, 55, 47–64, 2000.

    Google Scholar 

  42. Subrahmanyam, C., N. K. Thakur, T. Gangadhara Rao, R. Khanna, M. V. Ramanna, and V. Subrahmanyam, Tectonics of Bay of Bengal: new insights from satellite-gravity and ship-borne geophysical data, Earth and Planetary Sci. Lett., 171, 237–251, 1999.

    Article  Google Scholar 

  43. Thakur, N. K., M. V. Mahashabde, B. R. Arora, B. P. Singh, B. J. Srivastava, and S. N. Prasad, Geomagnetic variation anomalies in peninsular India, Geophys. J. R. Astron. Soc., 86, 839–854, 1986.

    Article  Google Scholar 

  44. Vasseur, G. and P. Weidelt, Bimodel electromagnetic induction in nonuniform thin sheets with an application to the northern Pyrenean induction anomaly, Geophys. J. R. Astron. Soc., 51, 669–690, 1977.

    Article  Google Scholar 

  45. Wang, L. J., F. E. M. Lilley, and F. H. Chamalaun, Large-scale electrical conductivity structure of Australia from the magnetometer arrays, Exploration Geophysics, 28, 150–155, 1997.

    Article  Google Scholar 

  46. Weaver, J. T., Regional induction in Scotland; and example of three-dimensional numerical modeling using the thin sheet approximation, Phys. Earth Planet. Inter., 28, 161–180, 1982.

    Article  Google Scholar 

  47. Weis, D., F. A. Frey, A. Saunders, I. Gibson, and leg 121 scientific ship-board party, Ninetyeast Ridge: A 5000 km record of a duple mantle plume, Geology, 19, 99–102, 1991.

    Article  Google Scholar 

Download references

Author information

Affiliations

Authors

Corresponding author

Correspondence to Baldev R. Arora.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Arora, B.R., Rao, P.B.V.S. Integrated modeling of EM response functions from Peninsular India and Bay of Bengal. Earth Planet Sp 54, 637–654 (2002). https://doi.org/10.1186/BF03353052

Download citation

Keywords

  • Thin Sheet
  • Indian Peninsula
  • Dharwar Craton
  • Equatorial Electrojet
  • Ninetyeast Ridge