1,2,4,- 1Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA, USA
- 2ETH Zurich, Geological Institute, Earth and Planetary Sciences, Zürich, Switzerland (semoon@ethz.ch)
- 3Department of Earth Sciences, University of Connecticut, Storrs, CT, USA
- 4Department of Geology and Geophysics, University of Wyoming, Laramie, WY, USA
- 5Department of Geography, Planning and Environment, Concordia University, QC, Canada
- 6Department of Geosciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
- 7Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC, USA
- 8School of Environmental and Life Sciences, University of Newcastle, Australia
- 9Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA, USA.
The deep critical zone both influences and is influenced by soil production and surface erosion in soil-mantled landscapes. However, few studies have examined the links among soil production rates (SPR), bedrock weathering in the deep critical zone, and landscape evolution. Here, we show that the evolution of the deep critical zone is modulated by near-surface residence times, reflecting the interplay between physical fracturing and chemical weathering. We integrate geophysical, geochemical, and cosmogenic nuclide data from the San Dimas Experimental Forest, California, USA. Our results demonstrate that deep bedrock weathering relates to soil production rates in different ways depending on its magnitude. In slowly eroding areas, soil production rates increase with increasing depth of bedrock weathering, reflecting the potential influences of topographic stress. In contrast, in rapidly eroding areas, soil production rates increase as the extent of bedrock weathering becomes shallower, reflecting limited chemical weathering under short residence times. These findings highlight the underappreciated co-evolution of deep bedrock weathering and soil production across the transition from soil-mantled to bedrock landscapes in actively eroding landscapes.
How to cite: Moon, S., Lee, J., Callahan, R., Riebe, C., Sklar, L., Carr, B., Holbrook, S., Flinchum, B., Weinheimer, N., Uecker, R., and Hidy, A.: Co-evolution of the critical zone: soil production and bedrock weathering, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8745, https://doi.org/10.5194/egusphere-egu26-8745, 2026.
