|
|
 |
|||||||||||||||||
|
|||||||||||||||||
 |
|||||||||||||||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
1 Wadia Institute of Himalayan Geology, Dehra Dun 248001 (U.P.), India
2 Department of Earth Sciences, Open University, Milton Keynes MK7 6AA, United Kingdom
3 Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, United Kingdom
Nd and Sr isotope systematics may provide important constraints on the location of major thrust systems that separate lithologically similar sedimentary sequences. The potential of the technique is illustrated by this isotopic study of the Main Central thrust system of the Himalaya. Nd isotope data from the Garhwal Himalaya indicate that metasedimentary rocks from the Vaikrita Group (
Nd = –14 to –19) correlate closely with those from the High Himalayan Crystalline Series, which constitutes the hanging-wall lithologies of the Main Central thrust. In contrast, metasedimentary rocks from the Munsiari Group (Nd = –23 to –28) show marked similarities to the Lesser Himalayan Series in the footwall of the Main Central thrust. Sr isotopes support the correlations in that the Vaikrita Group shows partial reequilibration at 500 Ma, whereas the Munsiari Group has not undergone Sr isotope homogenization since 1800 Ma. Thus, the Vaikrita thrust that juxtaposes these two formations is recognized as the Main Central thrust in Garhwal Himalaya. The thrust coincides, approximately, with the location of the kyanite isograd, confirming that inverted metamorphism is characteristic of both hanging wall and footwall of the Main Central thrust.
Along the Tons thrust (known locally as the Srinagar thrust) 50 km south of the Main Central thrust, low-grade quartzarenites with Nd-Sr isotope and trace element characteristics typical of Lesser Himalayan formations have been emplaced on phyllites and siltstones with geochemical characteristics of the High Himalayan Crystalline Series. The field relationships most probably result from out-of-sequence thrusting in which Lesser Himalayan Series rocks to the north were emplaced over low-grade equivalents of the High Himalayan Crystalline Series preserved in the external part of the orogen. This study establishes the value of isotope data for lithostratigraphic correlations within orogenic belts.
Key Words: correlation • Himalayan orogeny • isotope geochemistry • Main Central thrust • metasedimentary rocks
This article has been cited by other articles:
|
|
 |
|
  J. Celerier, T. M. Harrison, O. Beyssac, F. Herman, W. J. Dunlap, and A. A. G. Webb The Kumaun and Garwhal Lesser Himalaya, India: Part 2. Thermal and deformation histories Geological Society of America Bulletin, September 1, 2009; 121(9-10): 1281 - 1297. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Celerier, T. M. Harrison, A. A. G. Webb, and A. Yin The Kumaun and Garwhal Lesser Himalaya, India: Part 1. Structure and stratigraphy Geological Society of America Bulletin, September 1, 2009; 121(9-10): 1262 - 1280. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Groppo, F. Rolfo, and B. Lombardo P-T Evolution across the Main Central Thrust Zone (Eastern Nepal): Hidden Discontinuities Revealed by Petrology J. Petrology, June 1, 2009; 50(6): 1149 - 1180. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Carter and G. L. Foster Improving constraints on apatite provenance: Nd measurement on fission-track-dated grains Geological Society, London, Special Publications, January 1, 2009; 324(1): 57 - 72. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J.A. CHAMBERS, T.W. ARGLES, M.S.A. HORSTWOOD, N.B.W. HARRIS, R.R. PARRISH, and T. AHMAD Tectonic implications of Palaeoproterozoic anatexis and Late Miocene metamorphism in the Lesser Himalayan Sequence, Sutlej Valley, NW India Journal of the Geological Society, May 1, 2008; 165(3): 725 - 737. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Allen, A. Carter, Y. Najman, P.C. Bandopadhyay, H.J. Chapman, M.J. Bickle, E. Garzanti, G. Vezzoli, S. Ando, G.L. Foster, et al. New constraints on the sedimentation and uplift history of the Andaman-Nicobar accretionary prism, South Andaman Island Geological Society of America Special Papers, January 1, 2008; 436(0): 223 - 255. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. A. Murphy Isotopic characteristics of the Gurla Mandhata metamorphic core complex: Implications for the architecture of the Himalayan orogen Geology, November 1, 2007; 35(11): 983 - 986. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. M. Robinson, P. G. DeCelles, and P. Copeland Tectonic evolution of the Himalayan thrust belt in western Nepal: Implications for channel flow models Geological Society of America Bulletin, July 1, 2006; 118(7-8): 865 - 885. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Richards, R. Parrish, N. Harris, T. Argles, and L. Zhang Correlation of lithotectonic units across the eastern Himalaya, Bhutan Geology, May 1, 2006; 34(5): 341 - 344. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X. Mo, Z. Zhao, J. Deng, M. Flower, X. Yu, Z. Luo, Y. Li, S. Zhou, G. Dong, D. Zhu, et al. Petrology and geochemistry of postcollisional volcanic rocks from the Tibetan plateau: Implications for lithosphere heterogeneity and collision-induced asthenospheric mantle flow Geological Society of America Special Papers, January 1, 2006; 409(0): 507 - 530. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Godin, D. Grujic, R. D. Law, and M. P. Searle Channel flow, ductile extrusion and exhumation in continental collision zones: an introduction Geological Society, London, Special Publications, January 1, 2006; 268(1): 1 - 23. [Abstract] [PDF]
|
|
|
|
|
|
R. A. Jamieson, C. Beaumont, M. H. Nguyen, and D. Grujic Provenance of the Greater Himalayan Sequence and associated rocks: predictions of channel flow models Geological Society, London, Special Publications, January 1, 2006; 268(1): 165 - 182. [Abstract] [PDF]
|
|
|
|
|
|
D. M. Robinson and O. N. Pearson Exhumation of Greater Himalayan rock along the Main Central Thrust in Nepal: implications for channel flow Geological Society, London, Special Publications, January 1, 2006; 268(1): 255 - 267. [Abstract] [PDF]
|
|
|
|
|
|
A. J. Martin, P. G. DeCelles, G. E. Gehrels, P. J. Patchett, and C. Isachsen Isotopic and structural constraints on the location of the Main Central thrust in the Annapurna Range, central Nepal Himalaya Geological Society of America Bulletin, July 1, 2005; 117(7-8): 926 - 944. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. M. WILLIAMS, S. P. TURNER, J. A. PEARCE, S. P. KELLEY, and N. B. W. HARRIS Nature of the Source Regions for Post-collisional, Potassic Magmatism in Southern and Northern Tibet from Geochemical Variations and Inverse Trace Element Modelling J. Petrology, March 1, 2004; 45(3): 555 - 607. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Argles, G. Foster, A. Whittington, N. Harris, and M. George Isotope studies reveal a complete Himalayan section in the Nanga Parbat syntaxis Geology, December 1, 2003; 31(12): 1109 - 1112. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Huyghe, A. Galy, J.-L. Mugnier, and C. France-Lanord Propagation of the thrust system and erosion in the Lesser Himalaya: Geochemical and sedimentological evidence Geology, November 1, 2001; 29(11): 1007 - 1010. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Miller, C. MILLER, M. THONI, W. FRANK, B. GRASEMANN, U. KLOTZLI, P. GUNTLI, and E. DRAGANITS The early Palaeozoic magmatic event in the Northwest Himalaya, India: source, tectonic setting and age of emplacement Geological Magazine, May 1, 2001; 138(3): 237 - 251. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Prince, C. PRINCE, N. HARRIS, and D. VANCE Fluid-enhanced melting during prograde metamorphism Journal of the Geological Society, March 1, 2001; 158(2): 233 - 241. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Galy and C. France-Lanord Higher erosion rates in the Himalaya: Geochemical constraints on riverine fluxes Geology, January 1, 2001; 29(1): 23 - 26. [Abstract] [Full Text] [PDF]
|
|
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
