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Remagnetization of igneous rocks in Gupis area of Kohistan arc, northern Pakistan

Abstract

The Kohistan arc was formed due to subduction of neo-Tethyan oceanic crust beneath Asia. The arc is comprised of volcanic, plutonic and sedimentary rocks of Mesozoic to Tertiary age, formed prior and after the suturing of the Indian and Asian continents. Paleomagnetic investigations have been carried out on Paleocene volcanic and plutonic rocks exposed in the northern part of the arc. A total of 110 samples from 16 sites were drilled. According to rock-magnetic studies the main magnetic carrier is magnetite. Optical microscopy study reveals that low-grade metamorphism have effected all rocks. Magnetite is found as both a primary magmatic mineral and secondary alteration product in all samples. Samples of volcanics yield post tilting characteristic remanent magnetizations (ChRM). The in situ mean direction of the ChRMs of the intrusives is similar to the in situ mean direction of volcanics. The presence of secondary magnetite in plutons, the similarity of in situ mean ChRM of plutons with that of post-tilting ChRMs of similar age volcanics and dissimilarity of the mean ChRM of plutons from expected directions at the time of formation of plutons support a secondary origin for the ChRM of plutons. As the ChRM directions of the volcanics and intrusives are the same, it implies that both ChRMs were acquired during the same remagnetization event. Comparing the mean paleolatitude (25 ± 6°N) from Gupis area with those from Indian APWP and considering the fact that there was prevailing heating event in Lower Tertiary in the area, the acquisition age of this secondary remanent magnetization can be bracketed between 50 and 35 Ma.

References

  • Ade-Hall, J. M., H. C. Palmer, and T. P. Hubbard, The magnetic and opaque petrological response of basalts to regional hydrothermal alteration, Geophys. J. R. astr. Soc., 24, 137–174, 1971.

    Article  Google Scholar 

  • Ahmad, M. N., M. Yoshida, and Y. Fujiwara, Paleomagnetic study of Utror Volcanic Formation: Remagnetizations and postfolding rotations in Utror area, Kohistan arc, northern Pakistan, Earth Planets Space, 52, 425–436, 2000.

    Article  Google Scholar 

  • Appel, E., A. Patzelt, and C. Chouker, Secondary paleoremanences of Tethyan sediments from Zanskar Range (NW Himalaya), Geophys. J. Int., 122, 227–242, 1995.

    Article  Google Scholar 

  • Coward, M. P., R. W. H. Butler, M. A. Khan, and R. J. Knipe, The tectonic history of Kohistan and its implications for Himalayan structure, J. Geol. Soc. London, 144, 377–391, 1987.

    Article  Google Scholar 

  • Dunlop, D. J. and O. Ozdemir, Rock magnetism: fundamentals and frontiers, 573 pp., Cambridge University Press, New York, 1997.

    Book  Google Scholar 

  • Fisher, G.M., Dispersion on a sphere, Proc. R. Soc. London, A217, 295–305, 1953.

    Article  Google Scholar 

  • Khan, M. A., R. J. Stern, R. F. Gribble, and B. F. Windley, Geochemical and isotopic constraints on subduction polarity, magma sources, and palae-geography of Kohistan intra-oceanic arc, northern Pakistan Himalaya, J. Geol. Soc. London, 154, 935–946, 1999.

    Article  Google Scholar 

  • Kirschvink, J. L., The least squares line and plane and the analysis of the paleomagnetic data, Geophys. J. R. astr. Soc., 62, 699–718, 1980.

    Article  Google Scholar 

  • Klootwijk, C. T., A review of Indian Phanerozoic Paleomagnetism: Implications for the India-Asia collision, Tectonophys., 105, 331–353, 1984.

    Article  Google Scholar 

  • Klootwijk, C. T. and P. J. Conaghan, The extend of greater India, 1. Preliminary Paleomagnetic data from the Upper Devonian of the Eastern Hindukush, Chitral (Pakistan), Earth Planet. Sci. Lett., 42, 167–182, 1979.

    Article  Google Scholar 

  • Klootwijk, C. T., M. L. Sharma, J. Gergan, B. Tirkey, S. K. Shah, and V. Agarwal, The extend of Creater India, II. Paleomagnetic data from the Ladakh intrusives at Kargil, Northwestern Himalayas, Earth Planet. Sci. Lett., 44, 47–64, 1979.

    Article  Google Scholar 

  • Klootwijk, C. T., J. S. Gee, J. W. Percie, and G. M. Smith, Constraints on India-Asia Convergence: Paleomagnetic Results from Ninetyeast Ridge, in Proceedings of the Ocean Drilling Program, edited by J. Weissel, J. Peirce, E. Taylor, and J. Alt, Scientific Results, 121, pp. 777–881, 1991.

  • Klootwijk, C. T., P. J. Conaghan, R. Nazirullah, and K. De Jong, A. Further paleomagnetic data from Chitral (Eastern Hindukush): evidence for an early India-Asia contact, Tectonophys., 237, 1–25, 1994.

    Article  Google Scholar 

  • Middlemost, E., Magmas, Rocks and Planetary Development a survey of magma/igneous rock systems, 299 pp., Longman Singapore Publishers (Pte) Ltd., 1997.

  • Muffler, L. J. and D. E. White, Active metamorphism of Upper Cenozoic sediments in the Salton Sea Geothermal field and Salton Sea trough, South-eastern Califorinia, Bull. Geol. Soc. Am., 80, 157–180, 1969.

    Article  Google Scholar 

  • Ozdemir, O. and D.J. Dunlop, Low-temperature properties of a single crystal of magnetite oriented along principal magnetic axes, Earth Planet. Sci. Lett., 165, 229–239, 1999.

    Article  Google Scholar 

  • Ozdemir, O., D. J. Dunlop, and B. M. Moskowitz, The effect of oxidation on the Verwey Transition in Magnetite, Geophys. Res. Lett., 20, 1671–1674, 1993.

    Article  Google Scholar 

  • Petterson, M. G. and B. F. Windley, Rb-Sr dating of the Kohistan arc-batholith in the Trans Himalaya of north Pakistan, and tectonic implications, Earth Planet. Sci. Lett., 74, 45–57, 1985.

    Article  Google Scholar 

  • Pudsey, C. J., M. P. Coward, I. W. Luff, R. M. Shackelton, B. F. Windley, and M. Q. Jan, Collision zone between the Kohistan arc and Asian plate in NW Pakistan, Transaction of the Royal Society of Edinburg: Earth Sciences, 76, 463–479, 1985.

    Article  Google Scholar 

  • Pullaiah, G., E. Iriving, K. L. Buchan, and D. C. Dunlop, Magnetization changes caused by burial and uplift, Earth Planet. Sci. Lett., 28, 133–143, 1975.

    Article  Google Scholar 

  • Searle, M. P., Geology and Tectonics of the Karakoram Mountains, 358 pp., John Wiley & Sons, 1991.

  • Searle, M. P., M. A. Khan, J. E. Fraser, S. J. Gough, and M. Q. Jan, The tectonic evolution of Kohistan-Karakoram collision belt along Karakoram Highway transect, north Pakistan, Tectonics, 18, 929–949, 1999.

    Article  Google Scholar 

  • Sullivan, M. A., B. F. Windley, A. D. Saunders, J. R. Haynes, and D. C. Rex, A paleogeographic reconstruction of the Dir Group: evidence for magmatic arc migration within Kohistan, N. Pakistan, in Himalayan Tectonics, edited by P.J. Treloar and M. P.Searle, Geological Society London Special Publication 74, pp. 139–160, 1993.

  • Tahirkheli, R. A. K., M. Mattauer, F. Proust, and P. Tapponnier, The India-Eurasia Suture Zone In Northern Pakistan: Synthesis and interpretation of recent data at plate scale, in Geodynamics of Pakistan, edited by A. Farah and K. A. DeJong, pp. 125–130, Geol. Surv. Pakistan, Quetta, 1979.

    Google Scholar 

  • Treloar, P. J., D. C. Rex, P. G. Guise, M. P. Coward, M. P. Searle, B. F. Windeley, M. G. Petterson, M. Q. Jan, and I. F. Luff, K-Ar and Ar-Ar geochronology of Himalayan collision in NW Pakistan: constraints on the timing of suturing, deformation, metamorphism and uplift, Tectonics, 8, 881–909, 1989.

    Article  Google Scholar 

  • Treloar, P.J., M. G. Petterson, M. Q. Jan, and M.A. Sullivan, A re-evaluation of the stratigraphy and evolution of the Kohistan arc sequence, Pakistan Himalaya: implications for magmatic and tectonic arc-building processes, J. Geol. Soc. London, 153, 681–693, 1996.

    Article  Google Scholar 

  • Twiss, R. J. and E. M. Moores, Structural Geology, 532 pp., W. H. Freeman and Company, New York, 1992.

    Google Scholar 

  • Van der Voo, R., Paleomagnetism of the Atlantic, Tethys and lapetus oceans, 411 pp., Cambridge University Press, 1993.

  • Verwey, E. J. W., Electronic conductions of magnetite (Fe3O4) and its transition point at low temperature, Nature, 144, 327–328, 1939.

    Article  Google Scholar 

  • Zaman, H. and M. Torii, Paleomagnetic study of Cretaceous red beds from eastern Hindukush ranges, northern Pakistan: Paleoreconstruction of the Kohistan-Karakoram composite unit before the India-Asia collision, Geophys. J. Int., 136, 719–738, 1999.

    Article  Google Scholar 

  • Zeitler, P. K., Cooling History of the NW Himalaya, Pakistan, Tectonics, 4, 127–151, 1985.

    Article  Google Scholar 

  • Zijderveld, J. D. A., A. C. Demagnetization of rocks: Analysis of results, in Methods in Paleomagnetism, edited by D. W. Collisions, K. M. Creer, and S. K. Runcorn, 609 pp., Elsevier, New York, 1967.

    Google Scholar 

  • Zwing, A. and V. Bachtadse, Paleoposition of northern margin of Armorica in Late Devonian times: Paleomagnetic and rock magnetic results from Frankenstein Intrusive Complex (Mid-German Crystalline Rise), J. Geophys. Res., 105, 21445–21456, 2000.

    Article  Google Scholar 

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Correspondence to Mirza Naseer Ahmad.

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Ahmad, M.N., Fujiwara, Y. & Paudel, L.P. Remagnetization of igneous rocks in Gupis area of Kohistan arc, northern Pakistan. Earth Planet Sp 53, 373–384 (2001). https://doi.org/10.1186/BF03352394

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