Dr. Cliff Riebe

Bedrock Critical Zone Collaboration Network

I am currently serving as associate director of a new NSF-funded project focused on understanding linkages between subsurface weathering and surface processes across a network of sites spanning the lower 48 in the United States. This is exciting transdisciplinary work at the interface between water, rock, and life and involves collaboration with top scientists at seven institutions across the country. Students with an interest in critical-zone science, surface processes, and near-surface geophysics are encouraged to contact me and apply in the 2021-2022 application cycle for admission in Fall 2022. EAR 2012357

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Research Overview

My group seeks quantitative insight on processes that break rock down and move sediment across landscapes. To obtain it, we use a variety of geochemical, isotopic, and geophysical methods to measure properties of the surface and shallow subsurface. Together these measurements reveal patterns of erosion, weathering, regolith formation, and biogeochemical cycling. This work is vital to understanding connections between life and landscapes and to making advances in understanding how humans and natural processes shape Earth's dynamic surface.

Top Research Methods

• cosmogenic nuclides, which reveal long-term erosion rates of rock, soil & entire catchments;
• detrital thermochronometry, which sheds light on the sources of eroded material in streams and deposits;
• geochemical mass balance, which constrains the relative importance of chemical and physical erosion; &
• near-surface geophysics, which reveals the architecture of weathering and water storage in the critical zone.

Study Sites

Our research focuses on understanding the evolution of Earth's surface, with an emphasis on interpreting observations and measurements from the field. It should therefore come as no surprise that we often find ourselves in beautiful places around the world. In the latest project, which was funded as part of NSF's Critical Zone Collaboration Network, we will be doing work in eight mountain landscapes spanning the coterminous US.

Research Facilities

Cosmogenic Nuclide Labs: We oversee two spacious wet-chemical labs devoted to purification and dissolution of quartz and magnetite. Once minerals are dissolved, cosmogenic nuclides are extracted and prepared for analysis. We use these nuclides to measure rates of weathering, erosion, and sedimentation. Our cosmogenic nuclide lab facilities are open for use by collaborators on select projects. (Contact me by e-mail for information.)

Materials Characterization Labs: We have facilities for isolating other minerals, besides quartz; of particular interest to us at the moment is apatite, for detrital thermochronometry. We also boast a cottage industry in the geochemical analysis of soils and rock using XRF and XRD; this supports our quest for a quantitative understanding of weathering, erosion, and soil development in landscapes.

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Teaching

In my courses I challenge students to identify, understand, and quantify the chemical and physical processes that shape landscapes, generate soils, and modify water quality. My teaching approach emphasizes a mechanistic understanding of Earth systems, including hands-on field components and readings from current research whenever appropriate. Central in my teaching philosophy is the development of problem-solving skills and critical thinking abilities. Whenever possible, I include exercises based on my experience as an industry consultant – the goal is to help prepare our geology and geophysics graduates as best I can for the real-world problems they will face throughout their careers.

Recent Courses

• GEOL/ENR 4525/5525 Environmental Data Analysis (Fall)
• GEOL 4820 Capstone (Spring)
• GEOL 5200 Writing Science (Spring)

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Recent Publications

Citation statistics: [click here to open Google Scholar Author Site]

* denotes student author

Riebe, C. S., Callahan, R. P.*, Granke, S. B-M.*, Carr, B. J., Hayes, J. L., Shell, M. S.* & Sklar, L. S. 2021. Anisovolumetric weathering in granitic saprolite controlled by climate and erosion rate. Geology. 49.

Verdian, J.*, Sklar, L. S., Riebe, C. S., & Moore, J. R. 2021. Sediment size on talus slopes correlates with fracture spacing on bedrock cliffs: Implications for predicting initial sediment size distributions on hillslopes. Earth Surface Dynamics. 9: 1073–1090.

Preece, J. R.*, Shinker, J. J., Riebe, C. S., & Minckley, T. A. 2021. Elevation‐dependent precipitation response to El Niño‐Southern Oscillation revealed in headwater basins of the US central Rocky Mountains. International Journal of Climatology. 41, 2: 1199–1210.

Callahan, R. P.*, Riebe, C. S., Pasquet, S., Ferrier, K. L., Grana, D., Sklar, L. S., Taylor, N. J., Flinchum, B. A., Hayes, J. L., Carr, B. J., Hartsough, P. C., O’Geen, A. T. & Holbrook, W. S. 2020. Subsurface weathering revealed by hillslope-integrated porosity distributions. Geophysical Research Letters. 47, 15

Leone, J. D., Holbrook, W. S., Riebe, C. S., Chorover, J., Ferré, T. P. A., & Callahan, R. P.* 2020. Strong slope‐aspect control of regolith thickness by bedrock foliation Earth Surface Processes and Landforms. 45, 12: 2998–3010.

Sklar, L. S., Riebe, C. S., Genetti, J., Leclere, S., & Lukens, C. E.* 2020. Downvalley fining of hillslope sediment in an alpine catchment: Implications for downstream fining of sediment flux in mountain rivers. Earth Surface Processes and Landforms. 45: 1828–1845.

Lukens, C. E.*, Riebe, C. S., Sklar, L. S., & Shuster, D. L. 2020. Sediment size and abrasion biases in detrital thermochronology. Earth and Planetary Science Letters, 531, 115929.

Aarons, S. M., Arvin, L. J., Aciego, S. M., Riebe, C. S., Johnson, K. R., Blakowski, M. A., Koornneef, J. M., Hart, S. C., Barnes, M. E., Dove, N., Botthoff, J. K., Maltz, M., & Aronson, E. L., 2019. Competing droughts affect dust delivery to Sierra Nevada. Aeolian Research, 41, 100545.

Hayes, J. L.*, Riebe, C. S., Holbrook, W. S., Flinchum, B., & Hartsough, P. C. 2019. Porosity production in saprolite: Where volumetric strain dominates over chemical mass loss. Science Advances, 5, paper eaao0834

Holbrook, W. S., Marcon, V., Bacon, A., Brantley, S., Carr, B. J., Flinchum, B. A., Richter, D., Riebe, C. S. 2019. Links between physical and chemical weathering inferred from a 65-m-deep borehole through Earth’s critical zone. Scientific Reports, 9(1), paper 4495.

Callahan, R. P.*, Ferrier, K. L., Dixon, J., Dosseto, A., Hahm, W. J.*, Jessup, B. S.*, Hunsaker, C. T., Johnson, D. L., Sklar, L. S., Riebe, C. S., 2019. Arrested development: Erosional equilibrium in the southern Sierra Nevada, California, maintained by feedbacks between bedrock channel incision and hillslope sediment production. GSA Bulletin, 131, p. 1179–1202.

Richter, D. D., Billings, S. A., Groffman, P. M., Kelly, E. F., Lohse, K. A., McDowell, W. H., White, T. S., Anderson, S., Baldocchi, D. D., Banwart, S., Brantley, S., Braun, J. J., Brecheisen, Z. S., Cook, C. W., Hartnett, H. E., Hobbie, S. E., Kazanski, C., Gaillardet, J., Jobbagy, E., Jungkunst, H. F., Kazanski, C. E., Krishhnaswamy, J., Markewitz, D., O'Neill, Riebe, C. S., Schoeder, P., Siebe, C., Silver, W. L., Thompson, A., Verhoef, A., & Zhang, G. 2018. Ideas and perspectives: Strengthening the biogeosciences in environmental research networks. Biogeoscience, 15, p. 4815-4832.

Flinchum, B. A., Holbrook, W. S., Rempe, D., Moon, S., Riebe, C. S., Carr, B. J., Hayes, J. L., St. Clair, J., & Peters, M. P., 2018. Critical zone structure under a granite ridge inferred from drilling and three-dimensional seismic refraction data. Journal of Geophysical Research, Earth Surface, 123 (6), 1317-1343.

Klos, P. Z., Goulden, M., Riebe, C. S., Tague, C., O’Geen, A.T., Flinchum B.A., Safeeq, M. Conklin, M., Hart, S., Berhe, A.A., Hartsough, P., Holbrook, W.S., & Bales, R. 2018.  Subsurface plant-accessible water in mountain ecosystems with a Mediterranean climate.  Wiley Interdisciplinary Reviews (WIREs) Water 1277, p 1-14.

Huntington, K.W., Klepeis, K. A., with 66 community contributors (including Riebe, C.S.), 2018, Challenges and opportunities for research in tectonics: Understanding deformation and the processes that link Earth systems, from geologic time to human time. A community vision document submitted to the U.S. National Science Foundation. University of Washington, 84 pp., https://doi.org/10.6069/H52R3PQ5.

Arvin, L. J.*, Riebe, C. S., Aciego, S. M., & Blakowski, M. 2017 Global patterns of dust and bedrock nutrient supply to montane ecosystems. Science Advances 3, 1588.

Aciego, S. M., Riebe, C. S., Hart, S., Blakowski, M. A., Carey, C., Aarons, S. M., Dove, N., Botthoff, J. K., Sims, K. W. W., & Aronson, E. 2017. Dust outpaces bedrock in nutrient supply to forest ecosystems. Nature Communications 8: 14800

Riebe C. S., Hahm, W. J.*, & Brantley, S. L. 2017. Controls on deep critical zone architecture: A historical review and four testable hypotheses. Earth Surface Processes and Landforms 42: 128–156.

Sklar, L. S., Riebe, C. S., Marshall, J. A., Genetti, J., Leclere, S., Lukens, C. L.*, Merces, V. 2017. The problem of predicting the particle size distribution of sediment supplied by hillslopes to rivers. Geomorphology 277: 31–49.