Studia Geophysica et Geodaetica

, Volume 56, Issue 2, pp 595–619 | Cite as

A numerical model of exhumation of the orogenic lower crust in the Bohemian Massif during the Variscan orogeny

  • Petra Maierová
  • Ondřej Čadek
  • Ondrej Lexa
  • Karel Schulmann
Article

Abstract

We present a numerical model of the main phase (370–335 Ma) of the Variscan orogeny in the central part of the Bohemian Massif. The crustal deformation in our model is driven by radiogenic heating in the felsic lower crust, the lateral contraction of the Moldanubian domain due to convergence with the Saxothuringian plate (in the early stage of orogeny), and the indentation of the Brunovistulian basement into the weakened orogenic root (in the late stage). Our model explains the main geological events inferred from the geological record in the Moldanubian domain: formation of the orogenic plateau and onset of sedimentation at about 345 Ma, rapid exhumation of the orogenic lower crust at about 340 Ma and subsurface flow of crustal material (∼ 335 Ma and later). The results of our modeling suggest that delamination of the lithosphere, often invoked to explain the high temperature metamorphism in the orogenic lower crust of the Bohemian Massif, is not the only physical mechanism which can transfer a sufficient amount of heat to the crust to trigger its overturn.

Keywords

felsic granulites Moldanubian zone radiogenic heating delamination 

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References

  1. Arnold J., Jacoby W.R., Schmeling H. and Schott B., 2001. Continental collision and the dynamic and thermal evolution of the Variscan orogenic crustal root — numerical models. J. Geodyn., 31, 273–291.CrossRefGoogle Scholar
  2. Babuška V., Plomerová J. and Vecsey L., 2008. Mantle fabric of western Bohemian Massif (central Europe) constrained by 3D seismic P and S anisotropy. Tectonophysics, 462, 149–163.CrossRefGoogle Scholar
  3. Beard B.L., Medaris L.G., Johnson C.M., Jelínek E., Tonika J. and Riciputi L.R., 1995. Geochronology and geochemistry of eclogites from the Marianske Lazne Complex, Czech Republic — Implications for Variscan orogenesis. Geol. Rundsch., 84, 552–567.CrossRefGoogle Scholar
  4. Beaumont C., Jamieson R.A., Nguyen M.H. and Lee B., 2001. Himalayan tectonics explained by extrusion of a low-viscosity crustal channel coupled to focused surface denudation. Nature, 414, 738–742.CrossRefGoogle Scholar
  5. Beaumont C., Jamieson R.A., Nguyen M.H. and Ellis S., 2006. Crustal flow models in large hot orogens. Geol. Soc. London Spec. Publ., 268, 91–145, DOI: 10.1144/GSL.SP.2006.268.01.05.CrossRefGoogle Scholar
  6. Bielik M., Kloska K., Meurers B., Švancara J., Wybraniec S., Fancsik T., Grad M., Grand T., Guterch A., Katona M., Krolikowski C., Mikuška J., Pašteka R., Petecki Z., Polechońska O., Ruess D., Szalaiová V., Šefara J. and Vozár J., 2006. Gravity anomaly map of the CELEBRATION 2000 region. Geol. Carpath., 57, 145–156.Google Scholar
  7. Blankenbach B., Busse F., Christensen U., Cserepes L., Gunkel D., Hansen U., Harder H., Jarvis G., Koch M., Marquart G., Moore D., Olson P., Schmeling H. and Schnaubelt T., 1989. A benchmark comparison for mantle convection codes. Geophys. J. Int., 98, 23–38.CrossRefGoogle Scholar
  8. Buiter S.J.H., Babeyko A.Y., Ellis S., Gerya T.V., Kaus B.J.P., Kellner A., Schreurs G. and Yamada Y., 2006. The numerical sandbox: Comparison of model results for a shortening and an extension experiment. In: Buiter S.J.H. and Schreurs G. (Ed.), Analogue and Numerical Modelling of Crustal-Scale Processes. Geological Society, London, U.K., 29–64.Google Scholar
  9. Burov E. and Yamato P., 2008. Continental plate collision, P-T-t-z conditions and unstable vs. stable plate dynamics: Insights from thermomechanical modelling. Lithos, 103, 178–204.CrossRefGoogle Scholar
  10. Dallmeyer R.D. and Urban M., 1998. Variscan vs Cadomian tectonothermal activity in northwestern sectors of the Tepla-Barrandian zone, Czech Republic: constraints from Ar-40/Ar-39 ages. Geol. Rundsch., 87, 94–106.CrossRefGoogle Scholar
  11. Donea J., Huerta A., Ponthot J.-P. and Rodríguez-Ferran A., 2004. Arbitrary Lagrangian-Eulerian methods. In: Stein E., de Borst R. and Hughes T. (Eds.), Encyclopedia of Computational Mechanics, Volume 1: Fundamentals. John Wiley & Sons, 413–437.Google Scholar
  12. Dörr W. and Zulauf G., 2010. Elevator tectonics and orogenic collapse of a Tibetan-style plateau in the European Variscides: the role of the Bohemian shear zone. Int. J. Earth Sci., 99, 299–325.CrossRefGoogle Scholar
  13. Duretz T.M., Kaus B.J.P., Schulmann K., Gapais D. and Kermarrec J.-J., 2011. Indentation as an extrusion mechanism of lower crustal rocks in the Eastern Bohemian Massif: Insight from analogue and numerical modelling. Lithos, 124, 158–168.CrossRefGoogle Scholar
  14. Faccenda M., Gerya T.V. and Chakraborty S., 2008. Styles of postsubduction collisional orogeny: Influence of convergence velocity, crustal rheology and radiogenic heat production. Lithos, 103, 257–287.CrossRefGoogle Scholar
  15. Finger F., Roberts M.P., Haunschmid B., Schermaier A. and Steyrer H.P., 1997. Variscan granitoids of central Europe: their typology, potential sources and tectonothermal relations. Mineral. Petrol., 61, 67–96.CrossRefGoogle Scholar
  16. Franke W., 2000. The mid-European segment of the Variscides: tectonostratigraphic units, terrane boundaries and plate tectonic extension. In: Franke W., Altherr R., Haak V., Oncken O. and Tanner D. (Eds.), Orogenic Processes: Quantification and Modelling in the Variscan Belt. Geol. Soc. London Spec. Publ., 179, 35–61.Google Scholar
  17. Fritz H., Dallmeyer R.D. and Neubauer F., 1996. Thick-skinned versus thin-skinned thrusting: Rheology controlled thrust propagation in the Variscan collisional belt (The Southeastern Bohemian Massif, Czech Republic — Austria). Tectonics, 15, 1389–1413.CrossRefGoogle Scholar
  18. Fullsack P., 1995. An arbitrary Lagrangian-Eulerian formulation for creeping flows and its application in tectonic models. Geophys. J. Int., 120, 1–23.CrossRefGoogle Scholar
  19. Gerdes A., Worner G. and Henk A., 2000. Post-collisional granite generation and HT-LP metamorphism by radiogenic heating: the Variscan South Bohemian Batholith. J. Geol. Soc., 157, 577–587.CrossRefGoogle Scholar
  20. Gerya T.V. and Yuen D.A., 2003. Characteristics-based marker-in-cell method with conservative finite-differences schemes for modeling geological flows with strongly variable transport properties. Phys. Earth Planet. Inter., 140, 293–318.CrossRefGoogle Scholar
  21. Gerya T.V., Perchuk L.L. and Burg J.-P., 2008. Transient hot channels: Perpetrating and regurgitating ultrahigh-pressure, high-temperature crustmantle associations in collision belts. Lithos, 103, 236–256.CrossRefGoogle Scholar
  22. Guy A., Edel J.-B., Schulmann K., Tomek Č. and Lexa O., 2011. A geophysical model of the Variscan orogenic root (Bohemian Massif): Implications for modern collisional orogens. Lithos, 124, 144–157.CrossRefGoogle Scholar
  23. Hacker B.R, Kelemen P.B. and Behn M.D., 2011. Differentiation of the continental crust by relamination. Earth Planet. Sci. Lett., 307, 501–516.CrossRefGoogle Scholar
  24. Hartley A.J. and Otava J., 2001. Sediment provenance and dispersal in a deep marine foreland basin: the Lower Carboniferous Culm Basin, Czech Republic. J. Geol. Soc. London, 158, 137–150.CrossRefGoogle Scholar
  25. Hirth G., Teyssier C. and Dunlap W.J., 2001. An evaluation of quartzite flow laws based on comparisons between experimentally and naturally deformed rocks. Int. J. Earth Sci., 90, 77–87.CrossRefGoogle Scholar
  26. Hrubcová P., Sroda P., Špičák A., Guterch A., Grad M., Keller G.R., Brueckl E. and Thybo, H., 2005. Crustal and uppermost mantle structure of the Bohemian Massif based on CELEBRATION 2000 data. J. Geophys. Res., 110, B11305.CrossRefGoogle Scholar
  27. Janoušek V., Bowes D.R., Rogers G., Farrow C.M. and Jelínek E., 2000. Modelling diverse processes in the petrogenesis of a composite batholith: the Central Bohemian Pluton, Central European Hercynides. J. Petrol., 41, 511–543.CrossRefGoogle Scholar
  28. Kaus B., 2009. Factors that control the angle of shear bands in geodynamic numerical models of brittle deformation. Tectonophysics, 484, 36–47.CrossRefGoogle Scholar
  29. Kotková J., O’Brien P.J. and Ziemann M.A., 2011. Diamond and coesite discovered in Saxony-type granulite: Solution to the Variscan garnet peridotite enigma. Geology, 39, 667–670.CrossRefGoogle Scholar
  30. Lemiale V., Mühlhaus H.-B., Moresi L. and Stafford J., 2008. Shear banding analysis of plastic models formulated for incompressible viscous flows. Phys. Earth Planet. Inter., 171, 177–186.CrossRefGoogle Scholar
  31. Lexa O., Schulmann K., Janoušek V., Štípská P., Guy A. and Racek M., 2011. Heat sources and trigger mechanisms of exhumation of HP granulites in Variscan orogenic root. J. Metamorph. Geol., 29, 79–102.CrossRefGoogle Scholar
  32. Mackwell S.J., Zimmerman M.E. and Kohlstedt D.L., 1998. High-temperature deformation of dry diabase with application to tectonics on Venus. J. Geophys. Res., 103, 975–984.CrossRefGoogle Scholar
  33. Martin Y. and Church M., 1997. Diffusion in landscape development models: On the nature of basic transport relations. Earth Surf. Process. Landf., 22, 273–279.CrossRefGoogle Scholar
  34. Massonne H.J., 2006. Early metamorphic evolution and exhumation of felsic high-pressure granulites from the north-western Bohemian Massif. Mineral. Petrol., 86, 177–202.CrossRefGoogle Scholar
  35. Montgomery D.R. and Brandon M.T., 2002. Topographic controls on erosion rates in tectonically active mountain ranges. Earth Planet. Sci. Lett., 201, 481–489.CrossRefGoogle Scholar
  36. Ranalli G., 1995. Rheology of the Earth, 2nd Edition. Chapman and Hall, London, U.K.Google Scholar
  37. Schulmann K., Konopásek J., Janoušek V., Lexa O., Lardeaux J.-M., Edel J.-B., Štípská P. and Ulrich S., 2009. An Andean type Palaezoic convergence in the Bohemian Massif. C. R. Geosci., 341, 266–286.CrossRefGoogle Scholar
  38. Schulmann K., Lexa O., Štípská P., Racek M., Tajčmanová L., Konopásek J., Edel J.-B., Peschler A. and Lehmann J., 2008. Vertical extrusion and horizontal channel flow of orogenic lower crust: key exhumation mechanisms in large hot orogens? J. Metamorph. Geol., 26, 273–297.CrossRefGoogle Scholar
  39. Sobolev S.V. and Babeyko A.Y., 2005. What drives orogeny in the Andes? Geology, 33, 617–620.CrossRefGoogle Scholar
  40. Steltenpohl M.G., Cymerman Z., Krogh E.J. and Kunk M.J., 1993. Exhumation of eclogitized continental basement during Variscan lithospheric delamination and gravitational collapse, Sudety Mountains, Poland. Geology, 21, 1111–1114.CrossRefGoogle Scholar
  41. Štípská P. and Schulmann K., 1995. Inverted metamorphic zonation in a basement-derived nappe sequence; eastern margin of the Bohemian Massif. Geol. J., 30, 385–413.CrossRefGoogle Scholar
  42. Timmermann H., Dörr W., Krenn E., Finger F. and Zulauf G, 2006. Conventional and in situ geochronology of the Teplá crystalline unit, Bohemian Massif: implications for the processes involving monazite formation. Int. J. Earth Sci., 95, 629–647.CrossRefGoogle Scholar
  43. Turcotte D.L. and Schubert G., 2002. Geodynamics, 2nd Edition. Cambridge University Press. Cambridge, U.K.Google Scholar
  44. van Keken P.E., King S.D., Schmeling H., Christensen U.R., Neumeister D. and Doin M.-P., 1997. A comparison of methods for the modeling of thermomechanical convection. J. Geophys. Res., 102, 22477–22495.CrossRefGoogle Scholar
  45. Vanderhaeghe O., Medvedev S., Fullsack P., Beaumont C. and Jamieson R.A., 2003. Evolution of orogenic wedges and continental plateaux: insights from crustal thermal-mechanical models overlying subducting mantle lithosphere. Geophys. J. Int., 153, 27–51.CrossRefGoogle Scholar
  46. Watts A.B., 2001. Isostasy and Flexure of the Lithosphere. Cambridge University Press. Cambridge, U.K.Google Scholar
  47. Willner A.P., Sebazungu E., Gerya T.V., Maresch W.V. and Krohe A., 2002. Numerical modelling of PT-paths related to rapid exhumation of highpressure rocks from the crustal root in the Variscan Erzgebirge Dome (Saxony, Germany). J. Geodyn., 33, 281–314.CrossRefGoogle Scholar
  48. Winchester J.A. and PACE TMR Network Team, 2002. Palaeozoic amalgamation of Central Europe: new results from recent geological and geophysical investigations. Tectonophysics, 360, 5–21.CrossRefGoogle Scholar
  49. Žák J., Holub F. and Verner K., 2005. Tectonic evolution of a continental magmatic arc recorded by multiple episodically emplaced magma pulses: the Central Bohemian Plutonic Complex (Bohemian Massif, Czech Republic). Int. J. Earth Sci., 94, 385–400.CrossRefGoogle Scholar
  50. Zulauf G., 2001. Structural style, deformation mechanisms and paleodifferential stress along an exposed crustal section: constraints on the rheology of quartzofeldspathic rocks at supra- and infrastructural levels (Bohemian Massif). Tectonophysics, 332, 211–237.CrossRefGoogle Scholar

Copyright information

© Institute of Geophysics of the ASCR, v.v.i 2012

Authors and Affiliations

  • Petra Maierová
    • 1
  • Ondřej Čadek
    • 1
  • Ondrej Lexa
    • 2
  • Karel Schulmann
    • 3
  1. 1.Department of Geophysics, Faculty of Mathematics and PhysicsCharles University in PraguePraha 8Czech Republic
  2. 2.Institute of Petrology and Structural Geology, Faculty of ScienceCharles UniversityPraha 2Czech Republic
  3. 3.EOST, UMR 7516Université de StrasbourgStrasbourg CedexFrance

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