Articles | Volume 4, issue 3
https://doi.org/10.5194/esurf-4-685-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/esurf-4-685-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| Highlight paper
| 
29 Aug 2016
Research article | Highlight paper |
| 29 Aug 2016
Gravel threshold of motion: a state function of sediment transport disequilibrium?
Joel P. L. Johnson
CORRESPONDING AUTHOR
Department of Geological Sciences, The University of Texas, Austin, TX, USA
Related authors
Matanya Hamawi, Joel P. L. Johnson, Susan Bilek, Jens M. Turowski, and John B. Laronne
EGUsphere, https://doi.org/10.5194/egusphere-2025-591, https://doi.org/10.5194/egusphere-2025-591, 2025
This preprint is open for discussion and under review for Earth Surface Dynamics (ESurf).
Short summary
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Water level suddenly rises during flash floods in dry regions having a distinct impact on bedload – large sediment rolling and saltating on the riverbed. Using sensor-equipped pebbles and seismic monitoring in a field setting, we demonstrate that bedload activity is very high in both shallow and deep sudden flows. These findings can help improve bedload transport models, particularly when using seismic sensors, by providing new insights into bedload dynamics.
Claire C. Masteller, Joel P. L. Johnson, Dieter Rickenmann, and Jens M. Turowski
EGUsphere, https://doi.org/10.5194/egusphere-2024-3250, https://doi.org/10.5194/egusphere-2024-3250, 2024
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This paper presents a novel model that predicts the how gravel riverbeds may evolve in response to differences in the frequency and severity of flood events. We test our model using a 23-year long record of river flow and gravel transport from the Swiss Prealps. We find that our model reliably captures yearly patterns in gravel transport in this setting. Our new model is a major advance towards better predictions of river erosion that account for the flood history of a gravel bed river.
Sam Anderson, Nicole Gasparini, and Joel Johnson
Earth Surf. Dynam., 11, 995–1011, https://doi.org/10.5194/esurf-11-995-2023, https://doi.org/10.5194/esurf-11-995-2023, 2023
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We measured rock strength and amount of fracturing in the two different rock types, sandstones and carbonates, in Last Chance Canyon, New Mexico, USA. Where there is more carbonate bedrock, hills and channels steepen in Last Chance Canyon. This is because the carbonate-type bedrock tends to be more thickly bedded, is less fractured, and is stronger. The carbonate bedrock produces larger boulders than the sandstone bedrock, which can protect the more fractured sandstone bedrock from erosion.
Matanya Hamawi, Joel P. L. Johnson, Susan Bilek, Jens M. Turowski, and John B. Laronne
EGUsphere, https://doi.org/10.5194/egusphere-2025-591, https://doi.org/10.5194/egusphere-2025-591, 2025
This preprint is open for discussion and under review for Earth Surface Dynamics (ESurf).
Short summary
Short summary
Water level suddenly rises during flash floods in dry regions having a distinct impact on bedload – large sediment rolling and saltating on the riverbed. Using sensor-equipped pebbles and seismic monitoring in a field setting, we demonstrate that bedload activity is very high in both shallow and deep sudden flows. These findings can help improve bedload transport models, particularly when using seismic sensors, by providing new insights into bedload dynamics.
Claire C. Masteller, Joel P. L. Johnson, Dieter Rickenmann, and Jens M. Turowski
EGUsphere, https://doi.org/10.5194/egusphere-2024-3250, https://doi.org/10.5194/egusphere-2024-3250, 2024
Short summary
Short summary
This paper presents a novel model that predicts the how gravel riverbeds may evolve in response to differences in the frequency and severity of flood events. We test our model using a 23-year long record of river flow and gravel transport from the Swiss Prealps. We find that our model reliably captures yearly patterns in gravel transport in this setting. Our new model is a major advance towards better predictions of river erosion that account for the flood history of a gravel bed river.
Sam Anderson, Nicole Gasparini, and Joel Johnson
Earth Surf. Dynam., 11, 995–1011, https://doi.org/10.5194/esurf-11-995-2023, https://doi.org/10.5194/esurf-11-995-2023, 2023
Short summary
Short summary
We measured rock strength and amount of fracturing in the two different rock types, sandstones and carbonates, in Last Chance Canyon, New Mexico, USA. Where there is more carbonate bedrock, hills and channels steepen in Last Chance Canyon. This is because the carbonate-type bedrock tends to be more thickly bedded, is less fractured, and is stronger. The carbonate bedrock produces larger boulders than the sandstone bedrock, which can protect the more fractured sandstone bedrock from erosion.
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Stefan Hergarten
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Hao Chen, Xianyan Wang, Yanyan Yu, Huayu Lu, and Ronald Van Balen
Earth Surf. Dynam., 12, 163–180, https://doi.org/10.5194/esurf-12-163-2024, https://doi.org/10.5194/esurf-12-163-2024, 2024
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The Wei River catchment, one of the centers of the agricultural revolution in China, has experienced intense land use changes since 6000 BCE. This makes it an ideal place to study the response of river systems to anthropogenic land use change. Modeling results show the sensitivity of discharge and sediment yield to climate change increased abruptly when the agricultural land area exceeded a threshold at around 1000 BCE. This regime shift in the fluvial catchment led to a large sediment pulse.
Luke A. McGuire, Scott W. McCoy, Odin Marc, William Struble, and Katherine R. Barnhart
Earth Surf. Dynam., 11, 1117–1143, https://doi.org/10.5194/esurf-11-1117-2023, https://doi.org/10.5194/esurf-11-1117-2023, 2023
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Debris flows are mixtures of mud and rocks that can travel at high speeds across steep landscapes. Here, we propose a new model to describe how landscapes are shaped by debris flow erosion over long timescales. Model results demonstrate that the shapes of channel profiles are sensitive to uplift rate, meaning that it may be possible to use topographic data from steep channel networks to infer how erosion rates vary across a landscape.
Patrick Boyden, Paolo Stocchi, and Alessio Rovere
Earth Surf. Dynam., 11, 917–931, https://doi.org/10.5194/esurf-11-917-2023, https://doi.org/10.5194/esurf-11-917-2023, 2023
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Preservation bias often hampers the extraction of sea level changes from the stratigraphic record. In this contribution, we use a forward stratigraphic model to build three synthetic subtropical fringing reefs for a site in southwestern Madagascar (Indian Ocean). Each of the three synthetic reefs represents a different ice sheet melt scenario for the Pleistocene. We then evaluate each resultant reef sequence against the observed stratigraphic record.
Gregory A. Ruetenik, John D. Jansen, Pedro Val, and Lotta Ylä-Mella
Earth Surf. Dynam., 11, 865–880, https://doi.org/10.5194/esurf-11-865-2023, https://doi.org/10.5194/esurf-11-865-2023, 2023
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We compare models of erosion against a global compilation of long-term erosion rates in order to find and interpret best-fit parameters using an iterative search. We find global signals among exponents which control the relationship between erosion rate and slope, as well as other parameters which are common in long-term erosion modelling. Finally, we analyse the global variability in parameters and find a correlation between precipitation and coefficients for optimised models.
Stefan Hergarten and Alexa Pietrek
Earth Surf. Dynam., 11, 741–755, https://doi.org/10.5194/esurf-11-741-2023, https://doi.org/10.5194/esurf-11-741-2023, 2023
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The transition from hillslopes to channelized flow is typically attributed to a threshold catchment size in landform evolution models. Here we propose an alternative concept directly based on topography. Using this concept, channels and hillslopes self-organize, whereby the catchment size of the channel heads varies over some range. Our numerical results suggest that this concept works better than the established idea of a strict threshold catchment size.
Riccardo Reitano, Romano Clementucci, Ethan M. Conrad, Fabio Corbi, Riccardo Lanari, Claudio Faccenna, and Chiara Bazzucchi
Earth Surf. Dynam., 11, 731–740, https://doi.org/10.5194/esurf-11-731-2023, https://doi.org/10.5194/esurf-11-731-2023, 2023
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Tectonics and surface processes work together in shaping orogens through their evolution. Laboratory models are used to overcome some limitations of direct observations since they allow for continuous and detailed analysis of analog orogens. We use a rectangular box filled with an analog material made of granular materials to study how erosional laws apply and how erosion affects the analog landscape as a function of the applied boundary conditions (regional slope and rainfall rate).
Tzu-Yin Kasha Chen, Ying-Chen Wu, Chi-Yao Hung, Hervé Capart, and Vaughan R. Voller
Earth Surf. Dynam., 11, 325–342, https://doi.org/10.5194/esurf-11-325-2023, https://doi.org/10.5194/esurf-11-325-2023, 2023
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Predicting the extent and thickness of debris flow deposits is important for assessing and mitigating hazards. We propose a simplified mass balance model for predicting the morphology of terminated debris flows depositing over complex topography. A key element in this model is that the termination of flow of the deposit is determined by prescribed values of yield stress and friction angle. The model results are consistent with available analytical solutions and field and laboratory observations.
Richard Ott, Sean F. Gallen, and David Helman
Earth Surf. Dynam., 11, 247–257, https://doi.org/10.5194/esurf-11-247-2023, https://doi.org/10.5194/esurf-11-247-2023, 2023
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We compile data on carbonate denudation, the sum of mechanical erosion and chemical weathering, from cosmogenic nuclides and use them in conjunction with weathering data to constrain the partitioning of denudation into erosion and weathering. We show how carbonate erosion and weathering respond to different climatic and tectonic conditions and find that variations in denudation partitioning can be used to explain the vastly different morphology of carbonate landscapes on Earth.
Joanmarie Del Vecchio, Emma R. Lathrop, Julian B. Dann, Christian G. Andresen, Adam D. Collins, Michael M. Fratkin, Simon Zwieback, Rachel C. Glade, and Joel C. Rowland
Earth Surf. Dynam., 11, 227–245, https://doi.org/10.5194/esurf-11-227-2023, https://doi.org/10.5194/esurf-11-227-2023, 2023
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In cold regions of the Earth, thawing permafrost can change the landscape, impact ecosystems, and lead to the release of greenhouse gases. In this study we used many observational tools to better understand how sediment moves on permafrost hillslopes. Some topographic change conforms to our understanding of slope stability and sediment transport as developed in temperate landscapes, but much of what we observed needs further explanation by permafrost-specific geomorphic models.
Carole Petit, Tristan Salles, Vincent Godard, Yann Rolland, and Laurence Audin
Earth Surf. Dynam., 11, 183–201, https://doi.org/10.5194/esurf-11-183-2023, https://doi.org/10.5194/esurf-11-183-2023, 2023
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We present new tools in the landscape evolution model Badlands to simulate 10Be production, erosion and transport. These tools are applied to a source-to-sink system in the SW French Alps, where the model is calibrated. We propose a model that fits river incision rates and 10Be concentrations in sediments, and we show that 10Be in deep marine sediments is a signal with multiple contributions that cannot be easily interpreted in terms of climate forcing.
Cas Renette, Kristoffer Aalstad, Juditha Aga, Robin Benjamin Zweigel, Bernd Etzelmüller, Karianne Staalesen Lilleøren, Ketil Isaksen, and Sebastian Westermann
Earth Surf. Dynam., 11, 33–50, https://doi.org/10.5194/esurf-11-33-2023, https://doi.org/10.5194/esurf-11-33-2023, 2023
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One of the reasons for lower ground temperatures in coarse, blocky terrain is a low or varying soil moisture content, which most permafrost modelling studies did not take into account. We used the CryoGrid community model to successfully simulate this effect and found markedly lower temperatures in well-drained, blocky deposits compared to other set-ups. The inclusion of this drainage effect is another step towards a better model representation of blocky mountain terrain in permafrost regions.
Brian G. Sockness and Karen B. Gran
Earth Surf. Dynam., 10, 581–603, https://doi.org/10.5194/esurf-10-581-2022, https://doi.org/10.5194/esurf-10-581-2022, 2022
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To study channel network development following continental glaciation, we ran small physical experiments where networks slowly expanded into flat surfaces. By changing substrate and rainfall, we altered flow pathways between surface and subsurface. Initially, most channels grew by overland flow. As relief increased, erosion through groundwater sapping occurred, especially in runs with high infiltration and low cohesion, highlighting the importance of groundwater in channel network evolution.
Harrison K. Martin and Douglas A. Edmonds
Earth Surf. Dynam., 10, 555–579, https://doi.org/10.5194/esurf-10-555-2022, https://doi.org/10.5194/esurf-10-555-2022, 2022
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River avulsions (rivers suddenly changing course) redirect water and sediment. These floods can harm people and control how some landscapes evolve. We model how abandoned channels from older avulsions affect where, when, and why future avulsions occur in mountain-front areas. We show that abandoned channels can push and pull avulsions, and the way they heal controls landscapes. Avulsion models should include abandoned channels; we also highlight opportunities for future field workers.
Ariel Henrique do Prado, Renato Paes de Almeida, Cristiano Padalino Galeazzi, Victor Sacek, and Fritz Schlunegger
Earth Surf. Dynam., 10, 457–471, https://doi.org/10.5194/esurf-10-457-2022, https://doi.org/10.5194/esurf-10-457-2022, 2022
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Our work is focused on describing how and why the terrace levels of central Amazonia were formed during the last 100 000 years. We propose to address this question through a landscape evolution numerical model. Our results show that terrace levels at lower elevation were established in response to dry–wet climate changes and the older terrace levels at higher elevations most likely formed in response to a previously higher elevation of the regional base level.
Clément Desormeaux, Vincent Godard, Dimitri Lague, Guillaume Duclaux, Jules Fleury, Lucilla Benedetti, Olivier Bellier, and the ASTER Team
Earth Surf. Dynam., 10, 473–492, https://doi.org/10.5194/esurf-10-473-2022, https://doi.org/10.5194/esurf-10-473-2022, 2022
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Landscape evolution is highly dependent on climatic parameters, and the occurrence of intense precipitation events is considered to be an important driver of river incision. We compare the rate of erosion with the variability of river discharge in a mountainous landscape of SE France where high-magnitude floods regularly occur. Our study highlights the importance of the hypotheses made regarding the threshold that river discharge needs to exceed in order to effectively cut down into the bedrock.
Jean Braun
Earth Surf. Dynam., 10, 301–327, https://doi.org/10.5194/esurf-10-301-2022, https://doi.org/10.5194/esurf-10-301-2022, 2022
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By comparing two models for the transport of sediment, we find that they share a similar steady-state solution that adequately predicts the shape of most depositional systems made of a fan and an alluvial plain. The length of the fan is controlled by the size of the mountain drainage area feeding the sedimentary system and its slope by the incoming sedimentary flux. We show that the models differ in their transient behavior to external forcing and are characterized by different response times.
Léopold de Lavaissière, Stéphane Bonnet, Anne Guyez, and Philippe Davy
Earth Surf. Dynam., 10, 229–246, https://doi.org/10.5194/esurf-10-229-2022, https://doi.org/10.5194/esurf-10-229-2022, 2022
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Rivers are known to record changes in tectonic or climatic variation through long adjustment of their longitudinal profile slope. Here we describe such adjustments in experimental landscapes and show that they may result from the sole effect of intrinsic geomorphic processes. We propose a new model of river evolution that links long profile adjustment to cycles of river widening and narrowing. This result emphasizes the need to better understand control of lateral erosion on river width.
Elco Luijendijk
Earth Surf. Dynam., 10, 1–22, https://doi.org/10.5194/esurf-10-1-2022, https://doi.org/10.5194/esurf-10-1-2022, 2022
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The distance between rivers is a noticeable feature of the Earth's surface. Previous work has indicated that subsurface groundwater flow may be important for drainage density. Here, I present a new model that combines subsurface and surface water flow and erosion, and demonstrates that groundwater exerts an important control on drainage density. Streams that incise rapidly can capture the groundwater discharge of adjacent streams, which may cause these streams to become dry and stop incising.
Nikos Theodoratos and James W. Kirchner
Earth Surf. Dynam., 9, 1545–1561, https://doi.org/10.5194/esurf-9-1545-2021, https://doi.org/10.5194/esurf-9-1545-2021, 2021
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We examine stream-power incision and linear diffusion landscape evolution models with and without incision thresholds. We present a steady-state relationship between curvature and the steepness index, which plots as a straight line. We view this line as a counterpart to the slope–area relationship for the case of landscapes with hillslope diffusion. We show that simple shifts and rotations of this line graphically express the topographic response of landscapes to changes in model parameters.
Yanyan Wang and Sean D. Willett
Earth Surf. Dynam., 9, 1301–1322, https://doi.org/10.5194/esurf-9-1301-2021, https://doi.org/10.5194/esurf-9-1301-2021, 2021
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Although great escarpment mountain ranges are characterized by high relief, modern erosion rates suggest slow rates of landscape change. We question this interpretation by presenting a new method for interpreting concentrations of cosmogenic isotopes. Our analysis shows that erosion has localized onto an escarpment face, driving retreat of the escarpment at high rates. Our quantification of this retreat rate rationalizes the high-relief, dramatic landscape with the rates of geomorphic change.
William T. Struble and Joshua J. Roering
Earth Surf. Dynam., 9, 1279–1300, https://doi.org/10.5194/esurf-9-1279-2021, https://doi.org/10.5194/esurf-9-1279-2021, 2021
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We used a mathematical technique known as a wavelet transform to calculate the curvature of hilltops in western Oregon, which we used to estimate erosion rate. We find that this technique operates over 1000 times faster than other techniques and produces accurate erosion rates. We additionally built artificial hillslopes to test the accuracy of curvature measurement methods. We find that at fast erosion rates, curvature is underestimated, raising questions of measurement accuracy elsewhere.
Philippe Steer
Earth Surf. Dynam., 9, 1239–1250, https://doi.org/10.5194/esurf-9-1239-2021, https://doi.org/10.5194/esurf-9-1239-2021, 2021
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How landscapes respond to tectonic and climatic changes is a major issue in Earth sciences. I have developed a new model that solves for landscape evolution in two dimensions using analytical solutions. Compared to numerical models, this new model is quicker and more accurate. It can compute in a single time step the topography at equilibrium of a landscape or be used to describe its evolution through time, e.g. during changes in tectonic or climatic conditions.
Hemanti Sharma, Todd A. Ehlers, Christoph Glotzbach, Manuel Schmid, and Katja Tielbörger
Earth Surf. Dynam., 9, 1045–1072, https://doi.org/10.5194/esurf-9-1045-2021, https://doi.org/10.5194/esurf-9-1045-2021, 2021
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We study effects of variable climate–vegetation with different uplift rates on erosion–sedimentation using a landscape evolution modeling approach. Results suggest that regardless of uplift rates, transients in precipitation–vegetation lead to transients in erosion rates in the same direction of change. Vegetation-dependent erosion and sedimentation are influenced by Milankovitch timescale changes in climate, but these transients are superimposed upon tectonically driven uplift rates.
Stefan Hergarten
Earth Surf. Dynam., 9, 937–952, https://doi.org/10.5194/esurf-9-937-2021, https://doi.org/10.5194/esurf-9-937-2021, 2021
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This paper presents a new approach to modeling glacial erosion on large scales. The formalism is similar to large-scale models of fluvial erosion, so glacial and fluvial processes can be easily combined. The model is simpler and numerically less demanding than established models based on a more detailed description of the ice flux. The numerical implementation almost achieves the efficiency of purely fluvial models, so that simulations over millions of years can be performed on standard PCs.
Martine Simoes, Timothée Sassolas-Serrayet, Rodolphe Cattin, Romain Le Roux-Mallouf, Matthieu Ferry, and Dowchu Drukpa
Earth Surf. Dynam., 9, 895–921, https://doi.org/10.5194/esurf-9-895-2021, https://doi.org/10.5194/esurf-9-895-2021, 2021
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Elevated low-relief regions and major river knickpoints have for long been noticed and questioned in the emblematic Bhutan Himalaya. We document the morphology of this region using morphometric analyses and field observations, at a variety of spatial scales. Our findings reveal a highly unstable river network, with numerous non-coeval river captures, most probably related to a dynamic response to local tectonic uplift in the mountain hinterland.
Julien Seguinot and Ian Delaney
Earth Surf. Dynam., 9, 923–935, https://doi.org/10.5194/esurf-9-923-2021, https://doi.org/10.5194/esurf-9-923-2021, 2021
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Ancient Alpine glaciers have carved a fascinating landscape of piedmont lakes, glacial valleys, and mountain cirques. Using a previous supercomputer simulation of glacier flow, we show that glacier erosion has constantly evolved and moved to different parts of the Alps. Interestingly, larger glaciers do not always cause more rapid erosion. Instead, glacier erosion is modelled to slow down during glacier advance and peak during phases of retreat, such as the one the Earth is currently undergoing.
Eitan Shelef and Liran Goren
Earth Surf. Dynam., 9, 687–700, https://doi.org/10.5194/esurf-9-687-2021, https://doi.org/10.5194/esurf-9-687-2021, 2021
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Drainage basins are bounded by water divides (divides) that define their shape and extent. Divides commonly coincide with high ridges, but in places that experienced extensive tectonic deformation, divides sometimes cross elongated valleys. Inspired by field observations and using simulations of landscape evolution, we study how side channels that drain to elongated valleys induce pulses of divide migration, affecting the distribution of water and erosion products across mountain ranges.
Vipin Kumar, Imlirenla Jamir, Vikram Gupta, and Rajinder K. Bhasin
Earth Surf. Dynam., 9, 351–377, https://doi.org/10.5194/esurf-9-351-2021, https://doi.org/10.5194/esurf-9-351-2021, 2021
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Despite a history of landslide damming and flash floods in the NW Himalaya, only a few studies have been performed. This study predicts some potential landslide damming sites in the Satluj valley, NW Himalaya, using field observations, laboratory analyses, geomorphic proxies, and numerical simulations. Five landslides, comprising a total landslide volume of 26.3 ± 6.7 M m3, are found to have the potential to block the river in the case of slope failure.
Aaron Micallef, Remus Marchis, Nader Saadatkhah, Potpreecha Pondthai, Mark E. Everett, Anca Avram, Alida Timar-Gabor, Denis Cohen, Rachel Preca Trapani, Bradley A. Weymer, and Phillipe Wernette
Earth Surf. Dynam., 9, 1–18, https://doi.org/10.5194/esurf-9-1-2021, https://doi.org/10.5194/esurf-9-1-2021, 2021
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We study coastal gullies along the Canterbury coast of New Zealand using field observations, sample analyses, drones, satellites, geophysical instruments and modelling. We show that these coastal gullies form when rainfall intensity is higher than 40 mm per day. The coastal gullies are formed by landslides where buried channels or sand lenses are located. This information allows us to predict where coastal gullies may form in the future.
Riccardo Reitano, Claudio Faccenna, Francesca Funiciello, Fabio Corbi, and Sean D. Willett
Earth Surf. Dynam., 8, 973–993, https://doi.org/10.5194/esurf-8-973-2020, https://doi.org/10.5194/esurf-8-973-2020, 2020
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Looking into processes that occur on different timescales that span over thousands or millions of years is difficult to achieve. This is the case when we try to understand the interaction between tectonics and surface processes. Analog modeling is an investigating technique that can overcome this limitation. We study the erosional response of an analog landscape by varying the concentration of components of analog materials that strongly affect the evolution of experimental landscapes.
Stefan Hergarten
Earth Surf. Dynam., 8, 841–854, https://doi.org/10.5194/esurf-8-841-2020, https://doi.org/10.5194/esurf-8-841-2020, 2020
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Many contemporary models of large-scale fluvial erosion focus on the detachment-limited regime where all material entrained by the river is immediately excavated. This limitation facilitates the comparison with real river profiles and strongly reduces the numerical complexity. Here a simple formulation for the opposite case, transport-limited erosion, and a new numerical scheme that achieves almost the same numerical efficiency as detachment-limited models are presented.
Nikos Theodoratos and James W. Kirchner
Earth Surf. Dynam., 8, 505–526, https://doi.org/10.5194/esurf-8-505-2020, https://doi.org/10.5194/esurf-8-505-2020, 2020
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We non-dimensionalized a commonly used model of landscape evolution that includes an incision threshold. Whereas the original model included four parameters, we obtained a dimensionless form with a single parameter, which quantifies the relative importance of the incision threshold. Working with this form saves computational time and simplifies theoretical analyses.
Richard Barnes, Kerry L. Callaghan, and Andrew D. Wickert
Earth Surf. Dynam., 8, 431–445, https://doi.org/10.5194/esurf-8-431-2020, https://doi.org/10.5194/esurf-8-431-2020, 2020
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Maps of elevation are used to help predict the flow of water so we can better understand landslides, floods, and global climate change. However, modeling the flow of water is difficult when elevation maps include swamps, lakes, and other depressions. This paper explains a new method that overcomes these difficulties, allowing models to run faster and more accurately.
Stefan Hergarten
Earth Surf. Dynam., 8, 367–377, https://doi.org/10.5194/esurf-8-367-2020, https://doi.org/10.5194/esurf-8-367-2020, 2020
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Models of fluvial erosion have a long history in landform evolution modeling. Interactions between rivers and processes acting at hillslopes (e.g., landslides) are receiving growing interest in this context. While present-day computer capacities allow for applying such coupled models, there is still a scaling problem when considering rivers to be linear elements on a topography. Based on a reinterpretation of old empirical results, this study presents a new approach to overcome this problem.
Sara Savi, Stefanie Tofelde, Andrew D. Wickert, Aaron Bufe, Taylor F. Schildgen, and Manfred R. Strecker
Earth Surf. Dynam., 8, 303–322, https://doi.org/10.5194/esurf-8-303-2020, https://doi.org/10.5194/esurf-8-303-2020, 2020
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Fluvial deposits record changes in water and sediment supply. As such, they are often used to reconstruct the tectonic or climatic history of a basin. In this study we used an experimental setting to analyze how fluvial deposits register changes in water or sediment supply at a confluence zone. We provide a new conceptual framework that may help understanding the construction of these deposits under different forcings conditions, information crucial to correctly inferring the history of a basin.
Dirk Scherler and Wolfgang Schwanghart
Earth Surf. Dynam., 8, 245–259, https://doi.org/10.5194/esurf-8-245-2020, https://doi.org/10.5194/esurf-8-245-2020, 2020
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Drainage divides are believed to provide clues about divide migration and the instability of landscapes. Here, we present a novel approach to extract drainage divides from digital elevation models and to order them in a drainage divide network. We present our approach by studying natural and artificial landscapes generated with a landscape evolution model and disturbed to induce divide migration.
Dirk Scherler and Wolfgang Schwanghart
Earth Surf. Dynam., 8, 261–274, https://doi.org/10.5194/esurf-8-261-2020, https://doi.org/10.5194/esurf-8-261-2020, 2020
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Drainage divides are believed to provide clues about divide migration and the instability of landscapes. Here, we present a novel approach to extract drainage divides from digital elevation models and to order them in a drainage divide network. We present our approach by studying natural and artificial landscapes generated with a landscape evolution model and disturbed to induce divide migration.
Vincent Godard, Jean-Claude Hippolyte, Edward Cushing, Nicolas Espurt, Jules Fleury, Olivier Bellier, Vincent Ollivier, and the ASTER Team
Earth Surf. Dynam., 8, 221–243, https://doi.org/10.5194/esurf-8-221-2020, https://doi.org/10.5194/esurf-8-221-2020, 2020
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Slow-slipping faults are often difficult to identify in landscapes. Here we analyzed high-resolution topographic data from the Valensole area at the front of the southwestern French Alps. We measured various properties of hillslopes such as their relief and the shape of hilltops. We observed systematic spatial variations of hillslope morphology indicative of relative changes in erosion rates. These variations are potentially related to slow tectonic deformation across the studied area.
Helen W. Beeson and Scott W. McCoy
Earth Surf. Dynam., 8, 123–159, https://doi.org/10.5194/esurf-8-123-2020, https://doi.org/10.5194/esurf-8-123-2020, 2020
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We used a computer model to show that, when a landscape is tilted, rivers respond in a distinct way such that river profiles take on unique forms that record tilt timing and magnitude. Using this suite of river forms, we estimated tilt timing and magnitude in the Sierra Nevada, USA, and results were consistent with independent measures. Our work broadens the scope of tectonic histories that can be extracted from landscape form to include tilting, which has been documented in diverse locations.
Georg Trost, Jörg Robl, Stefan Hergarten, and Franz Neubauer
Earth Surf. Dynam., 8, 69–85, https://doi.org/10.5194/esurf-8-69-2020, https://doi.org/10.5194/esurf-8-69-2020, 2020
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The evolution of the drainage system in the Eastern Alps is inherently linked to different tectonic stages. This leads to a situation in which major orogen-parallel alpine rivers, such as the Salzach and the Enns, are characterized by elongated east–west-oriented catchments. We investigate the stability of present-day drainage divides and the stability of reconstructed paleo-drainage systems. Our results indicate a progressive stability of the network towards the present-day situation.
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Short summary
Accurately predicting gravel transport rates in mountain rivers is difficult because of feedbacks with channel morphology. River bed surfaces evolve during floods, influencing transport rates. I propose that the threshold of gravel motion is a state variable for channel reach evolution. I develop a new model to predict how transport thresholds evolve as a function of transport rate, and then use laboratory flume experiments to calibrate and validate the model.
Accurately predicting gravel transport rates in mountain rivers is difficult because of...
