The many surface expressions of mantle dynamics

Journal name:
Nature Geoscience
Volume:
3,
Pages:
825–833
Year published:
DOI:
doi:10.1038/ngeo1020
Published online

Abstract

Plate tectonic theory suggests that present-day topography can be explained by the repeated interactions between the tectonic plates moving along Earth's surface. However, mounting evidence indicates that a significant proportion of Earth's topography results from the viscous stresses created by flow within the underlying mantle, rather than by the moving plates. This dynamic topography is transient, varying as mantle flow changes, and is characterized by small amplitudes and long wavelengths. It is therefore often hidden by or confused with the more obvious topographic anomalies resulting from horizontal tectonic movements. However, dynamic topography can influence surface processes and thus enter the geological record; it has, for example, played a role in the establishment of Amazon drainage patterns. In turn, surface processes such as the erosion of topographical anomalies could affect mantle flow. This emerging view of dynamic topography suggests that the concept of plate tectonics as the driver of surface deformation needs to be extended to include the vertical coupling between the mantle and the surface. Unravelling this coupling back in time with the help of models and the geological record can potentially provide unprecedented insights into past mantle dynamics.

At a glance

Figures

  1. Dynamic topography.
    Figure 1: Dynamic topography.

    a, Simple sketch illustrating how flow in the mantle generates dynamic surface topography. The red and blue circles represent low (hot) and high (cold) density anomalies in the mantle; the black arrows represent the induced mantle flow; resulting dynamic topography is also shown. b, Normal, isostatically compensated, tectonic topography is created by thinning or thickening of the crust and lithosphere in response to tectonic plate motions (yellow arrows). Where plates converge, the crust is thickened and mountains (or positive topography) are created; where plates diverge, the crust is thinned and a basin forms. Note that the deflections of the surface and crust are highly exaggerated in both diagrams. Real Earth topography is only a few kilometres high, which is very small in comparison to its 6,700 km radius.

  2. Estimates of present-day dynamic topography.
    Figure 2: Estimates of present-day dynamic topography.

    a, Observed dynamic or 'residual' topography as computed by removing the isostatically compensated, tectonically driven component of surface topography. b, Dynamic topography as computed by a numerical model of mantle convection driven by density anomalies derived from seismic tomography images. c, Distribution of computed dynamic topography and its rate of change, as a function of wavelength (R. Moucha, personal communication). Parts a and b reproduced with permission from: a, ref. 6, © 2007 Elsevier; b, ref. 10, © 2008 Elsevier.

  3. Components needed to compute past dynamic topography.
    Figure 3: Components needed to compute past dynamic topography.

    a, Recent seismic station network recording large, distant earthquakes. Red dots correspond to seismic recording stations used to construct a global three-dimensional seismic image of the mantle as shown in b. The colour indicates the speed of seismic waves, blue is fast, red is slow. c, Example of the complex relationship between rock density (ρ) and seismic shear wave speed (Vs) as a function of depth, used to convert seismic tomography maps into density anomaly maps and drive mantle convection models, where R is the scaling between seismic velocity heterogeneity and density perturbations; for a discussion on the range of possible value for these parameters see refs 52, 56. d, Example of a radial viscosity profile used in numerical convection models. Figures reproduced with permission from: a,b, ref. 47, © 2008 Elsevier; c, ref. 55, © 2007 AGU; d, ref. 56, © 2007 Elsevier.

  4. The advection of present-day mantle-flow models backwards in time.
    Figure 4: The advection of present-day mantle-flow models backwards in time.

    Results of a numerical convection model (achieved following the steps illustrated in Fig. 3) showing computed temperature and velocity fields beneath North America (top panels), as well as the evolving dynamic topography over the past 100 Myr (bottom panels). In the top panels, the blue curve shows the model-predicted dynamic topography along the cross-section shown in the bottom panels; the red curve shows the predicted horizontal surface velocity (or plate motion) along the cross-section. Reproduced with permission from ref. 29, © 2009 AGU.

  5. Example of computed dynamic topography and its comparison to the geological record.
    Figure 5: Example of computed dynamic topography and its comparison to the geological record.

    Computed palaeogeographic maps (a,b) and corresponding dynamic topography (c,d) beneath Australia30, shown in a system of reference where Australia is fixed in its present-day position. The contours of dynamic topography (in metres) illustrate the rapid northward motion of the Australian plate relative to a large mantle downwelling that is responsible for the apparent sea-level variations along most of the continental margins. Magenta line corresponds to Pliocene palaeo-shoreline72. Red dots and labels correspond to the locations of wells used to constrain the model. Reproduced with permission from ref. 30, © 2010 Elsevier.

  6. How eroding dynamic topography can affect mantle flow.
    Figure 6: How eroding dynamic topography can affect mantle flow.

    Results of a three-dimensional viscous-flow numerical model illustrating the importance of how surface processes can accelerate flow in an isoviscous mantle. The time steps at which the results are shown are identical in the two experiments. In the first simulation, where surface processes are turned off (panels a–e), the rigid, light sphere rises almost twice as slowly as in the second simulation (panels f–j) where surface processes are sufficiently efficient to erode dynamic topography at the rate it is being created by mantle flow. See supplementary information for animations of these simulations.

  7. Earth's erosion rate compared with mantle anomalies' rising velocity.
    Figure 7: Earth's erosion rate compared with mantle anomalies' rising velocity.

    a, Sphere rising velocity versus imposed erosion rate (both normalized by the maximum rising velocity, that is measured in the full erosion experiment) as obtained in four separate numerical experiments, similar to those shown in Fig. 6. The rising velocity is the maximum value achieved by the sphere during the experiment. b, Rate of rise of a light sphere rising in the Earth's mantle, as a function of its radius. The Stokes velocity VStokes = 2/9((Drga2)/m) of an object is the rate at which a light, rigid sphere of equivalent volume rises in a viscous fluid, which depends only on its radius, a, the density contrast between the sphere and the fluid, Dr, the acceleration due to gravity, g, and the fluid viscosity, m. I have assumed a mean mantle viscosity of 5×1021 Pa·s and a density anomaly of 10 kg m−3, based on our best estimates of these values for the Earth's mantle as shown in Fig. 3b,c,d.

References

  1. Hager, B., Clayton, C., Richards, M., Comer, R. & Dziewonski, A. Lower mantle heterogeneity, dynamic topography and the geoid. Nature 313, 541545 (1985).
  2. Gurnis, M., Mitrovica, J., Ritsema, J. & van Heijst, H-J. Constraining mantle density structure using geological evidence of surface uplift rates: The case of the African superplume. Geochem. Geophys. Geosyst. 1, 1020 (2000).
  3. Lowry, A., Ribe, N. & Smith, R. Dynamic elevation of the Cordillera, western United States. J. Geophys. Res. 105, 2337123390 (2000).
  4. Conrad, C., Lithgow-Bertelloni, C. & Louden, K. Iceland, the Farallon slab, and dynamic topography of the North Atlantic. Geology 32, 177180 (2004).
  5. Guillou-Frotier, L., Burov, E., Nehlig, P. & Wyns, R. Deciphering plume–lithosphere interactions beneath Europe from topographic signatures. Glob. Planet. Change 58, 119140 (2007).
  6. Steinberger, B. Effects of latent heat release at phase boundaries on flow in the Earth's mantle, phase boundary topography and dynamic topography at the Earth's surface. Phys. Earth Planet. Inter. 164, 220 (2007).
  7. Adam, C. & Vidal, V. Mantle flow drives the subsidence of oceanic plates. Science 328, 8385 (2010).
  8. Hillier, J. Subsidence of normal seafloor: observations do indicate flattening. J. Geophys. Res. 115, B03102 (2010).
  9. Winterbourne, J., Crossby, A. & White, N. Depth, age and dynamic topography of oceanic lithosphere beneath heavily sedimented Atlantic margins. Earth Planet. Sci. Lett. 287, 137151 (2009).
  10. Moucha, R. et al. Dynamic topography and long-term sea-level variations: there is no such thing as a stable continental platform. Earth Planet. Sci. Lett. 271, 101108 (2008).
  11. Mitrovica, J., Beaumont, C. & Jarvis, G. Tilting of continental interiors by the dynamical effects of subduction. Tectonics 8, 10791094 (1989).
  12. Gurnis, M. Phanerozoic marine inundation of continents driven by dynamic topography above subducting slabs. Nature 364, 589593 (1993).
  13. Spasojevic, S., Liu, L., Gurnis, M. & Muller, R. The case for dynamic subsidence of the US east coast since the Eocene. Geophys. Res. Lett. 35, L08305 (2008).
  14. DiCaprio, L., Gurnis, M. & Muller, R. Long-wavelength tilting of the Australian continent since the Late Cretaceous. Earth Planet. Sci. Lett. 278, 175185 (2009).
  15. Husson, L. Dynamic topography above retreating subduction zones. Geology 34, 741744 (2006).
  16. Artyushkov, E. & Hofmann, A. Neotectonic crustal uplift on the continents and its possible mechanisms: the case of southern Africa. Surv. Geophys. 18, 369415 (1998).
  17. Burov, E. & Guillou-Frottier, L. The plume head-continental lithosphere interaction using a tectonically realistic formulation for the lithosphere. Geophys. J. Int. 161, 469490 (2005).
  18. Lithgow-Bertelloni, C. & Silver, P. Dynamic topography, plate driving forces and the African superswell. Nature 395, 269272 (1998).
  19. Guillaume, B., Martinod, J., Husson, L., Roddaz, M. & Riquelme, R. Neogene uplift of central eastern Patagonia: dynamic response to active spreading ridge subduction? Tectonics 28, TC2009 (2009).
  20. Sutherland, R., Spasojevic, S. & Gurnis, M. Mantle upwelling after Gondwana subduction death explains anomalous topography and subsidence histories of eastern New Zealand and West Antarctica. Geology 38, 155158 (2010).
  21. Muller, R., Sdrolias, M., Gaina, C., Steinberger, B. & Heine, C. Long-term sea-level fluctuations driven by ocean basin dynamics. Science 319, 13571362 (2008).
  22. Conrad, C. & Husson, L. Influence of dynamic topography on sea level and its rate of change. Lithosphere 1, 110120 (2009).
  23. Lovell, B. A pulse in the planet: regional control of high-frequency changes in relative sea level by mantle convection. J. Geol. Soc. Lond. 167, 637648 (2010).
  24. Petersen, K., Nielsen, S., Clausen, O., Stephenson, R. & Gerya, T. Small-scale mantle convection produces stratigraphic sequences in sedimentary basins. Science 329, 827830 (2010).
  25. Gallagher, K. & Lambeck, K. Subsidence, sedimentation and sea-level changes in the Eromanga Basin, Australia. Basin Res. 2, 115131 (1989).
  26. Gurnis, M., Muller, R. & Moresi, L. Cretaceous vertical motion of Australia and the Australian Antarctic discordance. Science 279, 14991504 (1998).
  27. Mitrovica, J., Pysklywec, R. & Beaumont, C. The Devonian to Permian tilting of the Russion platform: an example of subduction controlled long-wavelength tilting of continents. J. Geodyn. 22, 7996 (1996).
  28. Pysklywec, R. & Mitrovica, J. The role of subduction-induced subsidence in the evolution of the Karoo Basin. J. Geol. 107, 155164 (1999).
  29. Spasojevic, S., Liu, L. & Gurnis, M. Adjoint models of mantle convection with seismic, plate motion, and stratigraphic constraints: North America since the Late Cretaceous. Geochem. Geophys. Geosyst. 10, Q05W02 (2009).
  30. Heine, C., Muller, R., Steinberger, B. & DiCaprio, L. Integrating deep Earth dynamics in paleogeographic reconstructions of Australia. Tectonophysics 483, 135150 (2010).
  31. Gallagher, K. & Brown, R. The onshore record of passive margin evolution. J. Geol. Soc. Lond. 154, 451457 (1997).
  32. Gallagher, K. & Brown, R. in The Oil and Gas Habitats of the South Atlantic (eds Cameron, N., Bate, R. & Clure, V.) 4153 (Geological Society of London Special Publication Vol. 153, 1999).
  33. Walford, H. & White, N. Constraining uplift and denudation of west African continental margin by inversion of stacking velocity data. J. Geophys. Res. 110, B04403 (2005).
  34. Al-Hajri, Y., White, N. & Fishwick, S. Scales of transient convective support beneath Africa. Geology 37, 883886 (2009).
  35. Rudge, J., Shaw Champion, M., White, N., McKenzie, D. & Lovell, J. A plume model of transient diachronous uplift at the Earth's surface. Earth Planet. Sci. Lett. 267, 146160 (2008).
  36. Shaw Champion, M., White, N., Jones, S. & Lovell, J. Quantifying transient mantle convective uplift: an example from the Faroe–Shetland basin. Tectonics 27, TC1002 (2008).
  37. Heine, C., Muller, R., Steinberger, B. & Torsvik, T. Subsidence in intracontinental basins due to dynamic topography. Phys. Earth Planet. Inter. 171, 252264 (2008).
  38. Downey, N. & Gurnis, M. Instantaneous dynamics of the cratonic Congo basin. J. Geophys. Res. 114, B06401 (2009).
  39. DiCaprio, L., Muller, R. & Gurnis, M. A dynamic process for drowning carbonate reefs on the northeastern Australian margin. Geology 38, 1114 (2010).
  40. Moucha, R. et al. Deep mantle forces and the uplift of the Colorado Plateau. Geophys. Res. Lett. 36, L19310 (2009).
  41. Forte, A., Moucha, R., Simmons, N., Grand, S. & Mitrovica, J. Deep-mantle contributions to the surface dynamics of the North American continent. Tectonophysics 481, 315 (2010).
  42. Leng, W. & Zhong, S. Surface subsidence caused by mantle plumes and volcanic loading in large igneous provinces. Earth Planet. Sci. Lett. 291, 207214 (2010).
  43. Le Pourhiet, L., Gurnis, M. & Saleeby, J. Mantle instability beneath the Sierra Nevada Mountains in California and Death Valley extension. Earth Planet. Sci. Lett. 251, 104119 (2006).
  44. Conrad, C. & Gurnis, M. Seismic tomography, surface uplift, and the breakup of Gondwanaland: Integrating mantle convection backwards in time. Geochem. Geophys. Geosyst. 4, 1031 (2003).
  45. Liu, L., Spasojevic, S. & Gurnis, M. Reconstructing Farallon plate subduction beneath North America back to the Late Cretaceous. Science 322, 934938 (2008).
  46. Grand, S. Mantle shear-wave tomography and the fate of subducted slabs. Phil. Trans. R. Soc. Lond. A 360, 24752491 (2002).
  47. Li, C., van der Hilst, R., Engdahl, E. & Burdick, S. A new global model for P wave speed variations in Earth's mantle. Geochem. Geophys. Geosyst. 9, Q05018 (2008).
  48. Burdick, S. et al. Model update December 2008: upper mantle heterogeneity beneath North America from P-wave travel time tomography with global and USArray transportable array data. Seismol. Res. Lett. 80, 638645 (2008).
  49. Rawlinson, N., Pozgay, S. & Fishwick, S. Seismic tomography: a window into deep Earth. Phys. Earth Planet. Inter. 178, 101135 (2009).
  50. Karato, S.-I. & Karki, B. Origin of lateral variation of seismic wave velocities and density in the deep mantle. J. Geophys. Res. 106, 2177121784 (2001).
  51. Stixrude, L. & Lithgow-Bertelloni, C. Thermodynamics of mantle minerals. Part 1: Physical properties. Geophys. J. Int. 162, 610632 (2005).
  52. Simmons, N., Forte, A. & Grand, S. Joint seismic, geodynamic and mineral physical constraints on three-dimensional mantle heterogeneity: implications for the relative importance of thermal versus compositional heterogeneity. Geophys. J. Int. 177, 12841304 (2009).
  53. Ni, S., Tan, E., Gurnis, M. & Helmberger, D. Sharp sides to the African superplume. Science 296, 18501852 (2002).
  54. Behn, M., Conrad, C. & Silver, P. Detection of upper mantle flow associated with the African superplume. Earth Planet. Sci. Lett. 224, 259274 (2004).
  55. Simmons, N., Forte, A. & Grand, S. Thermomechanical structure and dynamics of the African super-plume. Geophys. Res. Lett. 34, L02301 (2007).
  56. Forte, A. in Treatise of Geophysics (eds Romanovicz, B. & Dziewonski, A.) 805854 (GEOTOP Publication Vol. 1, 2007).
  57. Tan, E., Choi, E., Thoutireddy, P., Gurnis, M. & Aivazis, M. Geoframework: coupling multiple models of mantle convection within a computational framework. Geochem, Geophys. Geosyst. 7, Q06001 (2006).
  58. Moucha, R., Forte, A., Mitrovica, J. & Daradich, A. Lateral variations in mantle rheology: implications for convection related surface observables and inferred viscosity models. Geophys. J. Int. 169, 113135 (2007).
  59. Bunge, H.-P., Hagelberg, C. & Travis, B. Mantle circulation models with variational data assimilation: Inferring past mantle flow and structure from plate motion histories and seismic tomography. Geophys. J. Int. 152, 280301 (2003).
  60. Liu, L. & Gurnis, M. Dynamic subsidence and uplift of the Colorado Plateau. Geology 38, 663666 (2010).
  61. Shephard, G. E., Muller, R. D., Liu, L. & Gurnis, M. Miocene drainage reversal of the Amazon River driven by plate–mantle interaction. Nature Geosci. 3, 870875 (2010).
  62. Shephard, G. et al. Contribution of mantle convection to shifting South American coastlines during the Tertiary. Eos 90, 52 (2009).
  63. Wegmann, K. et al. Position of the Snake River watershed divide as an indicator of geodynamic processes in the greater Yellowstone region, western North America. Geosphere 3, 272281 (2007).
  64. Beranek, L., Link, P. & Fanning, C. Miocene to Holocene landscape evolution of the western Snake River plain region, Idaho: using the SHRIMP detrital zircon provenance record to track eastward migration of the Yellowstone hotspot. Geol. Soc. Am. Bull. 118, 10271050 (2006).
  65. Karlstrom, K., Crow, R., Crossey, L., Coblentz, D. & van Wijk, J. Model for tectonically driven incision of the younger than 6 Ma Grand Canyon. Geology 36, 835838 (2008).
  66. Sandiford, M. The tilting continent: a new constraint on the dynamic topographic field from Australia. Earth Planet. Sci. Lett. 261, 152163 (2007).
  67. Finnegan, N. et al. Coupling of rock uplift and river incision in the Namche Barwa-Gyala Peri Massif, Tibet. Geol. Soc. Am. Bull. 120, 142155 (2008).
  68. Iaffaldano, G. & Bunge, H.-P. Strong plate coupling along the Nazca–South America convergent margin. Geology 36, 443446 (2008).
  69. Stadler, G. et al. The dynamics of plate tectonics and mantle flow: from local to global scales. Science 329, 10331038 (2010).
  70. Jault, D. & Le Moul, J.-L. Core–mantle boundary shape: constraints inferred from the pressure torque acting between the core and the mantle. Geophys. J. Int. 101, 233241 (2007).
  71. Simoes, M., Braun, J. & Bonnet, S. Continental-scale erosion and transport laws: A new approach to quantitatively investigate macroscale landscapes and associated sediment fluxes over the geological past. Geochem. Geophys. Geosyst. 11, Q09001 (2010).
  72. Langford, R., Wilford, G., Truswell, E. & Isern, A. Paleogeographic Atlas of Australia: Cainozoic (Australian Geological Survey Organization, 1995).

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  1. Laboratoire de Géodynamique des Chaînes Alpines, Université Joseph Fourier de Grenoble, 38041 Grenoble, France.
    jean.braun@ujf-grenoble.fr

    • Jean Braun

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