Crustal structure in the Siwalik Himalayas using magnetotelluric studies
Earth, Planets and Space volume 54, pages 19–30 (2002)
Tectonics in the Himalayan foothills is a result of the compressional forces active since the collision between Indian and Eurasian plates and is best understood as a combination of thin skin tectonics and the basement level faulting. In order to delineate the depth extent of various thrusts and faults, wide band Magnetotelluric (MT) studies were conducted at 17 stations over the Una-Mandi profile located in the Lesser Himalayas. These studies indicate that the Palampur thrust may be a composite of two thrust zones which merge together on the south of the MT profile and extends to depths of about 8 km. The Lambagraon syncline flanked by the Sarkaghat anticline on the NE and the Bahl anticline to the SW, is about 10 km deep. The crust is underlain by a conductive layer with a resistivity of about 100 Ω − m at depth of about 50 km below the Palampur thrust and Sarkaghat anticline. This layer is delineated at shallower depths of about 35 km below the Lambagraon syncline and also on the NE towards the main boundary thrust.
Ádám, A., The change of electrical structure between an orogenic and an ancient tectonic area, J. Geomag. Geoelectr., 32, 1–46, 1980.
Biswas, S. K., Status of exploration for Hydrocarbons in Siwalik basins of India and future trends, Himalayan Geology, 15, 283–300, 1994.
DST Expert group, Report of the expert group on the NW Himalayan geotransect programme (NWHGP), Earth system Science division, Department of Science and Technology, Govt of India, 1995 (unpublished).
Gansser, A., Geology of the Himalayas, 289 pp., Interscience Publ., New York, 1964.
Groom, R. W. and R. C. Bailey, Decomposition of the magnetotelluric impedance tensor in the presence of local three dimensional galvanic distortions, J. Geophys. Res., 94, 1913–1925, 1989.
Jones, A. G., Static shift of magnetotelluric data and its removal in a sedimentary basin environment, Geophysics, 51(7), 967–978, 1988.
Jones, A. G., Electrical conductivity of the continental lower crust, in Developments in Geotectonics, 23, Continental Lower Crust, edited by D. M. Fountain, R. Arculus, and R. W. Kay, pp. 87–143, Elsevier Science Publishers, Amsterdam, 1992.
Jones, A. G. and I. Dumas, Electromagnetic Image of a volcanic zone, Phys. Earth Planet. Inter., 81, 289–314, 1993.
Karunakaran, C. and A. Ranga Rao, Status of exploration for hydrocarbons in the Himalayan region—Contributions to stratigraphy and structure, Geol. Surv. India Misc. Publ., No:41, 1–66, 1976.
Mahadevan, T. M., Deep Continental structure of India: A review, Geol. Soc. India, Memoir No: 28, 348, 1994.
Ni, J. and M. Barazangi, Seismotectonics of the Himalayan collision zone: Geometry of the underthrusting Indian plate beneath the Himalaya, J. Geophys. Res., 89(B2), 1147–1163, 1984.
Pilgrim, A., Correlation of the Siwaliks with mammal horizons of Europe, Rec. Geol. Surv. India, 43, 1–264, 1913.
Raiverman, V., S. V. Kunte, and A. Mukerjea, Basin geometry, Cenozoic sedimentation and hydrocarbon prospects in north western Himalaya and Indo-Gangetic plains, Petroleum Asia Journal: Petroliferous basins of India, VI(4), 67–92, 1983.
Raiverman, V., A. K. Srivastava, and D. N. Prasad, Structural style in the northwestern Himalayan foothills, in Himalayan Geology Siwalik Foreland Basin of Himalaya, edited by R. Kumar, S. K. Ghosh, and N. R. Phadtare, 15, 263–280, Oxford & IBH publishing Co. Pvt. Ltd. New Delhi, 1994.
Ravi Shanker, Heat-flow map of India and discussions on its geological and economic significance, Indian Minerals, 42, 89–110, 1988.
Reddy, C. D. and B. R. Arora, Quantitative interpretation of geomagnetic induction response across the thrust zones of Himalaya along the Ganga Yamuna valley, J. Geomag. Geoelectr., 45, 775–785, 1993.
Rodi, W. and R. L. Mackie, Nonlinear conjugate gradients algorithm for 2D magnetotelluric inversions, Geophysics, 66, 174–187, 2001.
Vozoff, K., The magnetotelluric method in the exploration of sedimentary basins, Geophysics, 37, 98–141, 1972.
Wight, D. E. and F. X. Bostick, Cascade decimation A technique for real time estimation of power spectra, Proc. IEEE Intern. Conf. Accoustic, Speech Signal Processing, Denver, Colorado, April, 9–11, pp. 626–629, 1980.
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Gokarn, S.G., Rao, C.K. & Gupta, G. Crustal structure in the Siwalik Himalayas using magnetotelluric studies. Earth Planet Sp 54, 19–30 (2002). https://doi.org/10.1186/BF03352418