Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-02T22:31:37.613Z Has data issue: false hasContentIssue false
  • English
  • Français

Simple shear is not so simple! Kinematics and shear senses in Newtonian viscous simple shear zones

Published online by Cambridge University Press:  17 January 2012

SOUMYAJIT MUKHERJEE
SOUMYAJIT MUKHERJEE*
Affiliation:
Department of Earth Sciences, Indian Institute of Technology Bombay, Powai, Mumbai-400 076, Maharashtra, India
*
*E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

This work develops an analytical model of shear senses within an inclined ductile simple shear zone with parallel rigid boundaries and incompressible Newtonian viscous rheology. Taking account of gravity that tends to drive the material downdip and a possible pressure gradient that drives it upward along the shear zone, it is shown that (i) contradictory shear senses develop within two sub-zones even as a result of a single simple shear deformation; (ii) the highest velocity and least shear strain develop along the contact between the two sub-zones of reverse shear; (iii) for a uniform shear sense of the boundaries, a zone of reverse shear may develop within the top of the shear zone if the pressure gradient dominates the gravity component; otherwise it forms near the bottom boundary; (iv-a) a ‘pivot’ defined by the intersection between the velocity profile and the initial marker position distinguishes two sub-zones of opposite movement directions (not shear sense); (iv-b) a pivot inside any non-horizontal shear zone indicates a part of the zone that extrudes while the other subducts simultaneously; (v) the same shear sense develops: (v-a) when under a uniform shear of the boundaries, the shear zone remains horizontal and the pressure gradient vanishes; or alternatively (v-b) if the shear zone is inclined but the gravity component counterbalances the pressure gradient. Zones with shear sense reversal need to be reinterpreted since a pro-sheared sub-zone can retro-shear if the flow parameters change their magnitudes even though the same shear sense along the boundaries is maintained.

Keywords

simple shearshear zoneshear sensePoiseuille flowviscosityextrusionNewtonian fluid
Type
Original Articles
Information
Geological Magazine , Volume 149 , Issue 5 , September 2012 , pp. 819 - 826
Copyright
Copyright © Cambridge University Press 2012

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Annen, C., Scaillet, B. & Sparks, R. S. J. 2005. Thermal constraints on the emplacement rate of a large intrusive complex: the Manaslu Leucogranite, Nepal Himalaya. Journal of Petrology 47, 71–95.CrossRefGoogle Scholar
Beaumont, C., Jamieson, R. A., Nguyen, M. H. & Lee, B. 2001. Himalayan tectonics explained by extrusion of a low-viscosity crustal channel coupled to focused surface denudation. Nature 414, 738–42.CrossRefGoogle ScholarPubMed
Beaumont, C., Jamieson, R. A., Nguyen, M. H. & Medvedev, S. 2004. Crustal channel flows: 1. Numerical models with applications to the tectonics of the Himalayan-Tibetan orogen. Journal of Geophysical Research 109, 1–29.CrossRefGoogle Scholar
Berthé, D., Choukroune, P. & Jegouzo, P. 1979. Orthogneiss, mylonite and non-coaxial deformation of granites: the example from the south Armorican shear zone. Journal of Structural Geology 1, 31–42.CrossRefGoogle Scholar
Catlos, E. J., Harrison, T. M., Kohn, M. J., Grove, M., Ryerson, F. J., Manning, C. E. & Upreti, B. N. 2001. Geochronologic and thermobarometric constraints on the evolution of the Main Central Thrust, central Nepal Himalaya. Journal of Geophysical Research 106, 16177–204.CrossRefGoogle Scholar
Dasgupta, S., Chakraborty, S. & Neogi, S. 2009. Petrology of an inverted Barrovian sequence of metapelites in Sikkim Himalaya, India: constraints on the tectonics of inversion. American Journal of Science 309, 43–84.CrossRefGoogle Scholar
England, P. C. & Holland, T. J. B. 1979. Archimedes and the Tauern eclogites: the role of buoyancy in the preservation of exotic eclogite blocks. Earth and Planetary Science Letters 44, 287–94.CrossRefGoogle Scholar
Evans, A. M. 1980. An Introduction to Ore Geology. Oxford: Blackwell Scientific Publications.Google Scholar
Exner, U., Grasemann, B. & Mancktelow, N. S. 2006. Multiple faults in ductile simple shear: analogue models of flanking structure systems. In Analogue and Numerical Modelling of Crustal-Scale Processes (eds Butler, S. J. H. & Shreurs, G.), pp. 381–95. Geological Society of London, Special Publication no. 253.Google Scholar
Fraser, G., Worley, B. & Sandiford, M. 2000. High-precision geothermometry across the High Himalayan metamorphic sequence, Langtang Valley, Nepal. Journal of Metamorphic Geology 18, 665–81.CrossRefGoogle Scholar
Ganguli, J., Dasgupta, S., Cheng, W. & Neogi, S. 2000. Exhumation history of a section of the Sikkim Himalayas, India: records in the metamorphic mineral equilibria and compositional zoning of garnet. Earth and Planetary Science Letters 183, 471–86.CrossRefGoogle Scholar
Godin, L., Grujic, D., Law, R. D. & Searle, M. P. 2006. Channel flow, extrusion and extrusion in continental collision zones: an introduction. In Channel Flow, Ductile Extrusion and Exhumation in Continental Collision Zones (eds Law, R. D., Searle, M. P. & Godin, L.), pp 1–23. Geological Society of London, Special Publication no. 268.Google Scholar
Grasemann, B., Edwards, M. A. & Wiesmayr, G. 2006. Kinematic dilatancy effects on orogenic extrusion. In Channel Flow, Ductile Extrusion and Exhumation in Continental Collisional Zones (eds Law, R. D., Searle, M. P. & Godin, L.), pp 183–99. Geological Society of London, Special Publication no. 268.Google Scholar
Grujic, D., Casey, M., Davidson, C., Hollister, L. S., Kündig, R., Pavlis, T. & Schmid, S. 1996. Ductile extrusion of the Higher Himalayan Crystalline in Bhutan: evidence from quartz microfabrics. Tectonophysics 260, 21–43.CrossRefGoogle Scholar
Grujic, D., Hollister, L. S. & Parrish, R. R. 2002. Himalayan metamorphic sequence as an orogenic channel: insight from Bhutan. Earth and Planetary Science Letters 198, 177–91.CrossRefGoogle Scholar
Harrison, T. M., Ryerson, F. J., LeFort, P., Yin, A., Lovera, O. M. & Catlos, E. J. 1997. A Late Miocene–Pliocene origin for the Central Himalayan inverted metamorphism. Earth Planetary Science Letters 146, E1–E8.CrossRefGoogle Scholar
Hollister, L. S. 1993. The role of melt in the uplift and exhumation of orogenic belts. Chemical Geology 108, 31–48.CrossRefGoogle Scholar
Hollister, L. S. & Grujic, D. 2006. Pulsed channel flow in Bhutan. In Channel Flow, Ductile Extrusion and Exhumation in Continental Collision Zones (eds Law, R. D., Searle, M. P., Godin, L.), pp. 415–23. Geological Society of London, Special Publication no. 268.Google Scholar
Jain, A. K. & Anand, A. 1988. Deformational and strain patterns of an intracontinental ductile shear zone – an example from the Higher Garhwal Himalaya. Journal of Structural Geology 10, 717–34.CrossRefGoogle Scholar
Jain, A. K. & Patel, R. C. 1999. Structure of the Higher Himalayan Crystallines along the Suru-Doda Valleys (Zanskar), NW Himalaya. In Geodynamics of the NW Himalaya (eds Jain, A. K. & Manickavasagam, R. M.), pp. 91–110. Gondwana Research Group Memoir no. 6.Google Scholar
Kellett, D. A., Grujic, D., Warren, C., Cottle, J., Jamieson, R. & Tenzin, T. 2010. Metamorphic history of a syn-convergent orogen parallel detachment: the South Tibetan detachment system, Bhutan Himalaya. Journal of Metamorphic Geology 28, 785–808.CrossRefGoogle Scholar
Leech, M. L., Singh, S., Jain, A. K., Klemperer, S. & Manickavasagam, R. M. 2005. The onset of the India–Asia continental collision: early, steep subduction required by the timing of UHP metamorphism in the western Himalaya. Earth and Planetary Science Letters 234, 83–97.CrossRefGoogle Scholar
Li, Z. H., Gerya, T. V. & Burg, J. P. 2010. Influence of tectonic overpressure on P–T paths of HP–UHP rocks in continental collision zones: thermomechanical modeling. Journal of Metamorphic Geology 28, 227–47.CrossRefGoogle Scholar
Lombardo, B., Pertusati, P. & Borghi, S. 1993. Geology and tectonomagmatic evolution of the eastern Himalaya along the Chomolungma-Makalu transect. In Himalayan Tectonics (eds Treloar, P. & Searle, M. P.), pp 341–55. Geological Society of London, Special Publication no. 74.Google Scholar
Mancktelow, N. S. 2006. How ductile are ductile shear zones? Geology 34, 345–8.CrossRefGoogle Scholar
Mancktelow, N. S. 2008. Tectonic pressure: theoretical concepts and modeled examples. Lithos 103, 149–77.CrossRefGoogle Scholar
Marchildon, N. & Brown, M. 2003. Spatial distribution of melt-bearing structures in anatectic rocks from Southern Brittany, France: implications for melt transfer at grain- to orogen-scale. Tectonophysics 364, 215–35.CrossRefGoogle Scholar
Moores, E. M. & Twiss, R. J. 1995. Tectonics. New York: W. H. Freeman and Company, 187 pp.Google Scholar
Mukherjee, S. 2011. Mineral fish: their morphological classification, usefulness as shear sense indicators and genesis. International Journal of Earth Sciences 100, 1303–14.CrossRefGoogle Scholar
Mukherjee, S. & Koyi, H. A. 2010 a. Higher Himalayan Shear Zone, Sutlej section: structural geology and extrusion mechanism by various combinations of simple shear, pure shear and channel flow in shifting modes. International Journal of Earth Sciences 99, 1267–303.CrossRefGoogle Scholar
Mukherjee, S. & Koyi, H. A. 2010 b. Higher Himalayan Shear Zone, Zanskar Indian Himalaya – microstructural studies & extrusion mechanism by a combination of simple shear & channel flow. International Journal of Earth Sciences 99, 1083–110.CrossRefGoogle Scholar
Pai, S.-I. 1956. Viscous Flow Theory I – Laminar flow. New Jersey: D. Van Nostrand, 51 pp.Google Scholar
Papanastasiou, C. T., Georgiou, G. C. & Alexandrou, A. N. 2000. Viscous Fluid Flow. Florida: CRC Press.Google Scholar
Passchier, C. W. & Trouw, R. A. J. 2005. Microtectonics. Heidelberg: Springer.Google Scholar
Patel, R. C., Singh, S., Asokan, A. & Jain, A. K. 1993. Extensional tectonics in the Himalayan orogen, Zanskar, NW India. In Himalayan Tectonics (eds Treloar, P. J. & Searle, M. P.), pp. 445–59. Geological Society of London, Special Publication no. 74.Google Scholar
Ramsay, J. G. 1980. Shear zone geometry: a review. Journal of Structural Geology 2, 83–99.CrossRefGoogle Scholar
Ramsay, J. G. & Lisle, R. 2000. The Techniques of Modern Structural Geology, vol. 3: Applications of Continuum Mechanics in Structural Geology. San Francisco: Academic Press, 926 pp.Google Scholar
Regenauer-Lieb, K. & Yuen, D. A. 2003. Modeling shear zones in geological and planetary sciences: solid-and fluid-thermal-mechanical approaches. Earth-Science Reviews 63, 295–349.CrossRefGoogle Scholar
Scaillet, B., Holtz, F. & Pichavant, M. 1996. Viscosity of Himalayan leucogranites: implications for mechanisms of granite magma ascent. Journal of Geophysical Research 101, 27691–9.CrossRefGoogle Scholar
Schlichting, H. & Gersten, K. 1999. Boundary Layer Theory, 8th ed. Berlin: Springer.Google Scholar
Schulmann, K., Lexa, O., Štípská, P., Racek, M., Tajčmanová, L., Konopásek, J., Edel, J.-B., Peschler, A. & Lehmann, J. 2008. Vertical extrusion and horizontal channel flow of orogenic lower crust: key exhumation mechanisms in large hot orogens? Journal of Metamorphic Petrology 26, 273–97.CrossRefGoogle Scholar
Selverstone, J., Morteani, G. & Staude, J.-M. 1991. Fluid channelling during ductile shearing: transformation of granodiorite into aluminous schist in the Tauern Window, Eastern Alps. Journal of Metamorphic Geology 9, 419–31.CrossRefGoogle Scholar
Stüwe, K. 2007. Geodynamics of the Lithosphere, 2nd ed. Berlin: Springer, 325 pp.Google Scholar
Twiss, R. J. & Moores, E. M. 2007. Structural Geology, 2nd ed. New York: W. H. Freeman and Company, 736 pp.Google Scholar
Valdiya, K. S. 2001. Reactivation of terrane-defining boundary thrusts in central sectors of the Himalaya: implications. Current Science 81, 1418–31.Google Scholar
Vannay, J.-C. & Grasemann, B. 2001. Himalayan inverted metamorphism and syn-convergence extension as a consequence of a general shear extrusion. Geological Magazine 138, 253–76.CrossRefGoogle Scholar
von Huene, R., Ranero, C. R. & Scholl, D. W. 2009. Convergent margin structure in high-quality geophysical images and current kinematic and dynamic models. In Subduction Zone Geodynamics (eds Lallemand, S. & Funiciello, F.), pp. 137–57. Berlin, Heidelberg: Springer-Verlag.CrossRefGoogle Scholar
Warren, C. J., Beaumont, C. & Jamieson, R. A. 2008 a. Deep subduction and rapid exhumation: role of crustal strength and strain weakening in continental subduction and ultrahigh-pressure rock exhumation. Tectonics 27, TC6002.CrossRefGoogle Scholar
Warren, C. J., Beaumont, C. & Jamieson, R. 2008 b. Formation and exhumation of ultra-high-pressure rocks during continental collision: role of detachment in the subduction channel. Geochemistry Geophysics Geosystems 9, Q04019.CrossRefGoogle Scholar
Warren, C. J., Beaumont, C. & Jamieson, R. A. 2008 c. Modelling tectonic styles and ultra-high pressure (UHP) rock exhumation during the transition from oceanic subduction to continental collision. Earth and Planetary Science Letters 267, 129–45.CrossRefGoogle Scholar
Webb, S. L. & Dingwell, D. B. 1990. Non-Newtonian rheology of igneous melts at high stresses and strain rates: experimental results for rhyolites, andesites, basalt, and nephelinite. Journal of Geophysical Research 95, 15695–701.CrossRefGoogle Scholar
Weinberger, R., Lyakhovsky, V., Baer, G. & Begin, Z. B. 2006. Mechanical modeling and InSAR measurements of Mount Sedom uplift, Dead Sea basin: implications for effective viscosity of rock salt. Geochemistry Geophysics Geosystems 7, Q05014.CrossRefGoogle Scholar
Whipple, K. 2009. The influence of climate on the tectonic evolution of mountain belts. Nature Geoscience 2, 97–104.CrossRefGoogle Scholar
Wobus, C., Heimsath, A. & Whipple, K. 2005. Active out-of-sequence thrust faulting in the central Nepalese Himalaya. Nature 434, 1008–11.CrossRefGoogle ScholarPubMed
Yin, A. 2006. Cenozoic tectonic evolution of the Himalayan orogen as constrained by along-strike variation of structural geometry, exhumation history, and foreland sedimentation. Earth-Science Reviews 76, 1–131.CrossRefGoogle Scholar
Zhao, Z., Niu, Y., Christensen, N. I., Zhou, W., Hou, Q., Zhang, Z. M., Xie, H., Zhang, Z. C. & Liu, J. 2011. Delamination and ultra-deep subduction of continental crust: constraints from elastic wave velocity and density measurement in ultrahigh-pressure metamorphic rocks. Journal of Metamorphic Geology 29, 781–801.CrossRefGoogle Scholar