Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Flow in bedrock canyons

Subjects

Abstract

Bedrock erosion in rivers sets the pace of landscape evolution, influences the evolution of orogens and determines the size, shape and relief of mountains1,2. A variety of models link fluid flow and sediment transport processes to bedrock incision in canyons. The model components that represent sediment transport processes are increasingly well developed3,4,5. In contrast, the model components being used to represent fluid flow are largely untested because there are no observations of the flow structure in bedrock canyons. Here we present a 524-kilometre, continuous centreline, acoustic Doppler current profiler survey of the Fraser Canyon in western Canada, which includes 42 individual bedrock canyons. Our observations of three-dimensional flow structure reveal that, as water enters the canyons, a high-velocity core follows the bed surface, causing a velocity inversion (high velocities near the bed and low velocities at the surface). The plunging water then upwells along the canyon walls, resulting in counter-rotating, along-stream coherent flow structures that diverge near the bed. The resulting flow structure promotes deep scour in the bedrock channel floor and undercutting of the canyon walls. This provides a mechanism for channel widening and ensures that the base of the walls is swept clear of the debris that is often deposited there, keeping the walls nearly vertical. These observations reveal that the flow structure in bedrock canyons is more complex than assumed in the models presently used. Fluid flow models that capture the essence of the three-dimensional flow field, using simple phenomenological rules that are computationally tractable, are required to capture the dynamic coupling between flow, bedrock erosion and solid-Earth dynamics.

Your institute does not have access to this article

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Figure 1: Centreline transects of flow through a narrow bedrock canyon of the Fraser River.
Figure 2: Cross-sections of horizontal velocity magnitude and vertical velocity in Black Canyon downstream of a constriction.
Figure 3: Conceptual model of flow in a bedrock canyon.

References

  1. Whipple, K. X. The influence of climate on the tectonic evolution of mountain belts. Nature Geosci. 2, 97–104 (2009)

    CAS  ADS  Article  Google Scholar 

  2. Whipple, K. X., DiBiase, R. A. & Crosby, B. T. in Treatise on Geomorphology (eds Shroder, J. & Wohl, E. ) Vol. 9 Fluvial Geomorphology 550–573 (Academic Press, 2013)

    Book  Google Scholar 

  3. Sklar, L. S. & Dietrich, W. E. A mechanistic model for river incision into bedrock by saltating bed load. Wat. Resour. Res. 40, W06301 (2004)

    ADS  Article  Google Scholar 

  4. Lamb, M. P., Dietrich, W. E. & Sklar, L. S. A model for fluvial bedrock incision by impacting suspended and bed load sediment. J. Geophys. Res. 113, F03025 (2008)

    ADS  Google Scholar 

  5. Chatanantavet, P. & Parker, G. Physically based modeling of bedrock incision by abrasion, plucking, and macroabrasion. J. Geophys. Res. 114, F04018 (2009)

    ADS  Article  Google Scholar 

  6. Ferrier, K. L., Huppert, K. L. & Perron, J. T. Climatic control of bedrock incision. Nature 496, 206–209 (2013)

    CAS  ADS  Article  Google Scholar 

  7. Finnegan, N. J., Schumer, R. & Finnegan, S. A signature of transience in bedrock river incision rates over timescales of 104–107 years. Nature 505, 391–394 (2014)

    CAS  ADS  Article  Google Scholar 

  8. Willett, S. D. et al. Dynamic reorganization of river basins. Science 343, http://dx.doi.org/10.1126/science.1248765 (2014)

  9. Howard, A. D. & Kerby, G. Channel changes in badlands. Geol. Soc. Am. Bull. 94, 739–752 (1983)

    ADS  Article  Google Scholar 

  10. Seidl, M. A. & Dietrich, W. E. The problem of channel erosion into bedrock. Catena (Suppl.) 23, 101–124 (1992)

    Google Scholar 

  11. Howard, A. D., Dietrich, W. E. & Seidl, M. A. Modeling fluvial erosion on regional and continental scales. J. Geophys. Res. 99, 13971–13986 (1994)

    ADS  Article  Google Scholar 

  12. Seidl, M. A., Dietrich, W. E. & Kirchner, J. W. Longitudinal profile development into bedrock: an analysis of Hawaiian channels. J. Geol. 102, 457–474 (1994)

    ADS  Article  Google Scholar 

  13. Stark, C. P. A self-regulating model of bedrock river channel geometry. Geophys. Res. Lett. 33, L04402 (2006)

    ADS  Article  Google Scholar 

  14. Barbour, J. R. et al. Magnitude-frequency distributions of boundary shear stress along a rapidly eroding bedrock river. Geophys. Res. Lett. 36, L04401 (2009)

    ADS  Article  Google Scholar 

  15. Turowski, J. M., Lague, D. & Hovius, N. Response of bedrock channel width to tectonic forcing: insights from a numerical model, theoretical considerations, and comparison with field data. J. Geophys. Res. 114, F03016 (2009)

    ADS  Article  Google Scholar 

  16. DiBiase, R. A. & Whipple, K. X. The influence of erosion thresholds and runoff variability on the relationships among topography, climate, and erosion rate. J. Geophys. Res. 116, F04036 (2011)

    ADS  Article  Google Scholar 

  17. Tucker, G. E. & Hancock, G. R. Modelling landscape evolution. Earth Surf. Process. Landf. 35, 28–50 (2010)

    ADS  Article  Google Scholar 

  18. Howard, A. D. A detachment-limited model of drainage basin evolution. Wat. Resour. Res. 30, 2261–2285 (1994)

    ADS  Article  Google Scholar 

  19. Nelson, P. A. & Seminara, G. Modeling the evolution of bedrock channel shape with erosion from saltating bed load. Geophys. Res. Lett. 38, L17406 (2011)

    ADS  Article  Google Scholar 

  20. Wobus, C. W., Tucker, G. E. & Anderson, R. S. Self-formed bedrock channels. Geophys. Res. Lett. 33, L18408 (2006)

    ADS  Google Scholar 

  21. Leopold, L. B., Wolman, M. G. & Miller, J. P. Fluvial Processes in Geomorphology (Freeman, 1964)

    Google Scholar 

  22. Venditti J. G., et al., eds. in Coherent Flow Structures at Earth’s Surface 1–16 (Wiley, 2013)

  23. MacVicar, B. J. & Rennie, C. D. Flow and turbulence redistribution in a straight artificial pool. Wat. Resour. Res. 48, W02503 (2012)

    ADS  Article  Google Scholar 

  24. MacVicar, B. J., Obach, L. & Best, J. L. in Coherent Flow Structures at Earth’s Surface (eds Venditti, J. G. et al.) 243–259 (Wiley, 2013)

    Book  Google Scholar 

  25. Nezu, I. & Nakagawa, H. Turbulence in Open-Channel Flows 96–110 (A. A. Balkema, 1993)

    Google Scholar 

  26. Yang, S.-Q. Velocity distribution and wake-law in gradually decelerating flows. J. Hydraul. Res. 47, 177–184 (2009)

    Article  Google Scholar 

  27. Finnegan, N. J., Sklar, L. S. & Fuller, T. K. Interplay of sediment supply, river incision, and channel morphology revealed by the transient evolution of an experimental bedrock channel. J. Geophys. Res. 112, F03S11 (2007)

    ADS  Article  Google Scholar 

  28. Fuller, T. K. Field, Experimental and Numerical Investigations into the Mechanisms and Drivers of Lateral Erosion in Bedrock Rivers. PhD thesis, Univ. Minnesota. (2013)

  29. Rennie, C. D. & Church, M. Mapping spatial distributions and uncertainty of water and sediment flux in a large gravel bed river reach using an acoustic Doppler current profiler. J. Geophys. Res. 115, F03035 (2010)

    ADS  Article  Google Scholar 

  30. Jamieson, E. C. et al. 3-D flow and scour near a submerged wing dike: ADCP measurements on the Missouri River. Wat. Resour. Res. 47, W07544 (2011)

    ADS  Article  Google Scholar 

  31. Bathurst, J. C., Thorne, C. R. & Hey, R. D. Direct measurements of secondary currents in river bends. Nature 269, 504–506 (1977)

    ADS  Article  Google Scholar 

  32. Kean, J. W. & Smith, J. D. in Riparian Vegetation and Fluvial Geomorphology (eds Bennett S. J. & Simon, A. ) 237–252 (AGU, 2004)

    Book  Google Scholar 

  33. Kironoto, B. A. & Graf, W. H. Turbulence characteristics in rough non-uniform open-channel flow. Proc. ICE 112, 336–348 (1995)

    Google Scholar 

Download references

Acknowledgements

This study was supported by Natural Science and Engineering Research Council grants to M.C., J.G.V. and C.D.R. We thank D. Baerg and his crew at Fraser River Raft Expeditions for undertaking the logistics of the river traverse, R. DiBiase for reviewing an early draft of the manuscript, and M. Lin and C. Adderley for assistance with data processing.

Author information

Authors and Affiliations

Authors

Contributions

M.C. planned and organized the field campaign and provided guidance through the analysis. J.G.V., C.D.R. and M.C. performed the survey and supervised data processing and analysis by J.B., R.W.B and M.L. J.G.V. analysed the data and wrote the manuscript with input from C.D.R. and M.C.

Corresponding author

Correspondence to Jeremy G. Venditti.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Extended data figures and tables

Extended Data Figure 1 Bedrock canyons of the Fraser River, British Columbia.

From Quesnel to Yale, the river crosses the Interior Plateau where the surficial rock is dominantly volcanic, with sedimentary rock along the river. From Lillooet Rapid to Chilliwack, the river flows along a fault between the Coast Mountains to the west and the Cascade Mountains to the east.

Extended Data Figure 2 ADCP measurement survey through the entrance to Black Canyon.

a, Satellite image of Black Canyon with black lines across the channel marking the entrance and exit of the canyon. b, Velocity profile measurement locations (red dots) obtained using the 1,200-kHz ADCP. The surveyed length was 700 m. c, Bed topography measurement locations (blue dots) from the ADCP. The image is from the Ikonos satellite on 11 July 2007, processed by GeoEye/DigitalGlobe and accessed via ESRI ArcGIS software (http://www.esri.com/).

Extended Data Figure 3 Interpolated bed topography at the entrance to Black Canyon.

Interpolated using kriging onto a regular 2 m grid. Canyon walls were assumed to be vertical where there are no other data available. The channel margins are defined by the water level in aerial photos, where discharge is approximately 6,440 m3 s−1 at Hope.

Source data

Extended Data Figure 4 Example of an interpolated velocity magnitude grid in Black Canyon.

Velocity magnitude is defined as (Un2 + Ue2 + Uw2)0.5, where Un is the Northing, Ue is the Easting and Uw is the vertical velocity. The interpolation is done in Tecplot (http://www.tecplot.com/) software using kriging on a three-dimensional grid generated using the prism grid function with a vertical resolution of 0.25 m, and a horizontal resolution of 2 m. Interpolated velocities are shown with a 30% transparency so that all data in the three-dimensional grid can be seen.

Source data

Supplementary information

Video 1

Animation of cross-stream slices through a grid of the horizontal velocity magnitude field in Black Canyon. (MP4 10172 kb)

Video 2

Animation of cross-stream slices through a grid of the vertical velocity field in Black Canyon (MP4 9864 kb)

PowerPoint slides

Source data

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Venditti, J., Rennie, C., Bomhof, J. et al. Flow in bedrock canyons. Nature 513, 534–537 (2014). https://doi.org/10.1038/nature13779

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature13779

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing