Articles | Volume 5, issue 3
https://doi.org/10.5194/esurf-5-571-2017
© Author(s) 2017. 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-5-571-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
18 Sep 2017
Research article |
| 18 Sep 2017
Possible threshold controls on sediment grain properties of Peruvian coastal river basins
Camille Litty
CORRESPONDING AUTHOR
Institute of Geological Sciences, University of Bern, Baltzerstrasse 1 + 3, 3012 Bern, Switzerland
Fritz Schlunegger
Institute of Geological Sciences, University of Bern, Baltzerstrasse 1 + 3, 3012 Bern, Switzerland
Willem Viveen
Grupo de Investigación en Geología Sedimentaria, Sección de Ingeniería de Minas, Departamento de Ingeniería, Pontificia Universidad Católica del Perú, Av. Universitaria 1801, San Miguel, Lima, Peru
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K. P. Norton, F. Schlunegger, and C. Litty
Earth Surf. Dynam., 4, 147–157, https://doi.org/10.5194/esurf-4-147-2016, https://doi.org/10.5194/esurf-4-147-2016, 2016
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Cut-fill terraces are common landforms throughout the world. Their distribution both in space and time is not clear-cut, as they can arise from numerous processes. We apply a climate-dependent regolith production algorithm to determine potential sediment loads during climate shifts. When combined with transport capacity, our results suggest that the cut-fill terraces of western Peru can result from transient stripping of hillslope sediment but not steady-state hillslope erosion.
Michael Margreth, Florian Lustenberger, Dorothea Hug Peter, Fritz Schlunegger, and Massimiliano Zappa
Nat. Hazards Earth Syst. Sci. Discuss., https://doi.org/10.5194/nhess-2024-78, https://doi.org/10.5194/nhess-2024-78, 2024
Preprint under review for NHESS
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Recession models (RM) are crucial for observing the low flow behavior of a catchment. We developed two novel RM, which are designed to represent slowly draining catchment conditions. With a newly designed low flow prediction procedure we tested the prediction capability of these two models and three others from literature. One of our novel products delivered the best results, because it best represents the slowly draining catchment conditions.
Fritz Schlunegger, Edi Kissling, Dimitri Tibo Bandou, Guilhem Amin Douillet, David Mair, Urs Marti, Regina Reber, Patrick Fabian Schläfli, and Michael Alfred Schwenk
EGUsphere, https://doi.org/10.5194/egusphere-2024-683, https://doi.org/10.5194/egusphere-2024-683, 2024
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Overdeepenings are bedrock depressions filled with sediment. We combine the results of a gravity survey with drilling data to explore the morphology of such a depression beneath the city of Bern. We find that the target overdeepening comprises two basins >200 m deep. They are separated by a bedrock riegel that itself is cut by narrow canyons up to 150 m deep. We postulate that these structures formed underneath a glacier, where erosion by subglacial meltwater caused the formation of the canyons.
Daniel Bolliger, Fritz Schlunegger, and Brian W. McArdell
Nat. Hazards Earth Syst. Sci., 24, 1035–1049, https://doi.org/10.5194/nhess-24-1035-2024, https://doi.org/10.5194/nhess-24-1035-2024, 2024
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We analysed data from the Illgraben debris flow monitoring station, Switzerland, and we modelled these flows with a debris flow runout model. We found that no correlation exists between the grain size distribution, the mineralogical composition of the matrix, and the debris flow properties. The flow properties rather appear to be determined by the flow volume, from which most other parameters can be derived.
Ariel Henrique do Prado, David Mair, Philippos Garefalakis, Chantal Schmidt, Alexander Whittaker, Sebastien Castelltort, and Fritz Schlunegger
Hydrol. Earth Syst. Sci., 28, 1173–1190, https://doi.org/10.5194/hess-28-1173-2024, https://doi.org/10.5194/hess-28-1173-2024, 2024
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Engineering structures known as check dams are built with the intention of managing streams. The effectiveness of such structures can be expressed by quantifying the reduction of the sediment flux after their implementation. In this contribution, we estimate and compare the volumes of sediment transported in a mountain stream for engineered and non-engineered conditions. We found that without check dams the mean sediment flux would be ca. 10 times larger in comparison with the current situation.
Renas Koshnaw, Jonas Kley, and Fritz Schlunegger
EGUsphere, https://doi.org/10.5194/egusphere-2023-3123, https://doi.org/10.5194/egusphere-2023-3123, 2024
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This study investigates how Earth's geodynamic processes shaped the NW Zagros in the Middle East. The Neogene foreland basin underwent subsidence due to the load of surface and the subducting slab, and was later influenced by the Neotethys horizontal slab tear propagation in the late Miocene and the northward flow of mantle material.
David Mair, Ariel Henrique Do Prado, Philippos Garefalakis, Alessandro Lechmann, Alexander Whittaker, and Fritz Schlunegger
Earth Surf. Dynam., 10, 953–973, https://doi.org/10.5194/esurf-10-953-2022, https://doi.org/10.5194/esurf-10-953-2022, 2022
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Grain size data are important for studying and managing rivers, but they are difficult to obtain in the field. Therefore, methods have been developed that use images from small and remotely piloted aircraft. However, uncertainty in grain size data from such image-based products is understudied. Here we present a new way of uncertainty estimation that includes fully modeled errors. We use this technique to assess the effect of several image acquisition aspects on grain size uncertainty.
Michael A. Schwenk, Laura Stutenbecker, Patrick Schläfli, Dimitri Bandou, and Fritz Schlunegger
E&G Quaternary Sci. J., 71, 163–190, https://doi.org/10.5194/egqsj-71-163-2022, https://doi.org/10.5194/egqsj-71-163-2022, 2022
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We investigated the origin of glacial sediments in the Bern area to determine their route of transport either with the Aare Glacier or the Valais Glacier. These two ice streams are known to have joined in the Bern area during the last major glaciation (ca. 20 000 years ago). However, little is known about the ice streams prior to this last glaciation. Here we collected evidence that during a glaciation about 250 000 years ago the Aare Glacier dominated the area as documented in the deposits.
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.
Alessandro Lechmann, David Mair, Akitaka Ariga, Tomoko Ariga, Antonio Ereditato, Ryuichi Nishiyama, Ciro Pistillo, Paola Scampoli, Mykhailo Vladymyrov, and Fritz Schlunegger
Geosci. Model Dev., 15, 2441–2473, https://doi.org/10.5194/gmd-15-2441-2022, https://doi.org/10.5194/gmd-15-2441-2022, 2022
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Muon tomography is a technology that is used often in geoscientific research. The know-how of data analysis is, however, still possessed by physicists who developed this technology. This article aims at providing geoscientists with the necessary tools to perform their own analyses. We hope that a lower threshold to enter the field of muon tomography will allow more geoscientists to engage with muon tomography. SMAUG is set up in a modular way to allow for its own modules to work in between.
Michael A. Schwenk, Patrick Schläfli, Dimitri Bandou, Natacha Gribenski, Guilhem A. Douillet, and Fritz Schlunegger
Sci. Dril., 30, 17–42, https://doi.org/10.5194/sd-30-17-2022, https://doi.org/10.5194/sd-30-17-2022, 2022
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A scientific drilling was conducted into a bedrock trough (overdeepening) in Bern-Bümpliz (Switzerland) in an effort to advance the knowledge of the Quaternary prior to 150 000 years ago. We encountered a 208.5 m-thick succession of loose sediments (gravel, sand and mud) in the retrieved core and identified two major sedimentary sequences (A: lower, B: upper). The sedimentary suite records two glacial advances and the subsequent filling of a lake sometime between 300 000 and 200 000 years ago.
Emilija Krsnik, Katharina Methner, Marion Campani, Svetlana Botsyun, Sebastian G. Mutz, Todd A. Ehlers, Oliver Kempf, Jens Fiebig, Fritz Schlunegger, and Andreas Mulch
Solid Earth, 12, 2615–2631, https://doi.org/10.5194/se-12-2615-2021, https://doi.org/10.5194/se-12-2615-2021, 2021
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Here we present new surface elevation constraints for the middle Miocene Central Alps based on stable and clumped isotope geochemical analyses. Our reconstructed paleoelevation estimate is supported by isotope-enabled paleoclimate simulations and indicates that the Miocene Central Alps were characterized by a heterogeneous and spatially transient topography with high elevations locally exceeding 4000 m.
Renas I. Koshnaw, Fritz Schlunegger, and Daniel F. Stockli
Solid Earth, 12, 2479–2501, https://doi.org/10.5194/se-12-2479-2021, https://doi.org/10.5194/se-12-2479-2021, 2021
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As continental plates collide, mountain belts grow. This study investigated the provenance of rocks from the northwestern segment of the Zagros mountain belt to unravel the convergence history of the Arabian and Eurasian plates. Provenance data synthesis and field relationships suggest that the Zagros Mountains developed as a result of the oceanic crust emplacement on the Arabian continental plate, followed by the Arabia–Eurasia collision and later uplift of the broader region.
Owen A. Anfinson, Daniel F. Stockli, Joseph C. Miller, Andreas Möller, and Fritz Schlunegger
Solid Earth, 11, 2197–2220, https://doi.org/10.5194/se-11-2197-2020, https://doi.org/10.5194/se-11-2197-2020, 2020
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We present new U–Pb age data to provide insights into the source of sediment for the Molasse Sedimentary Basin in Switzerland. The paper aims to help shed light on the processes that built the Central Alpine Mountains between ~35 and ~15 Ma. A primary conclusion drawn from the results is that at ~21 Ma there was a significant change in the sediment sources for the basin. We feel this change indicates major tectonic changes within the Central Alps.
Samuel Mock, Christoph von Hagke, Fritz Schlunegger, István Dunkl, and Marco Herwegh
Solid Earth, 11, 1823–1847, https://doi.org/10.5194/se-11-1823-2020, https://doi.org/10.5194/se-11-1823-2020, 2020
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Based on thermochronological data, we infer thrusting along-strike the northern rim of the Central Alps between 12–4 Ma. While the lithology influences the pattern of thrusting at the local scale, we observe that thrusting in the foreland is a long-wavelength feature occurring between Lake Geneva and Salzburg. This coincides with the geometry and dynamics of the attached lithospheric slab at depth. Thus, thrusting in the foreland is at least partly linked to changes in slab dynamics.
Fritz Schlunegger, Romain Delunel, and Philippos Garefalakis
Earth Surf. Dynam., 8, 717–728, https://doi.org/10.5194/esurf-8-717-2020, https://doi.org/10.5194/esurf-8-717-2020, 2020
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We calculated the probability of sediment transport in coarse-grained mountainous streams in the Alps and the Andes where data on water discharge is available. We find a positive correlation between the predicted probability of sediment transport and the grain size sorting of the bed material. We suggest that besides sediment discharge, the bedload sorting exerts a significant influence on the mobility of sediment and thus on the stability of gravel bars in mountainous streams.
David Mair, Alessandro Lechmann, Romain Delunel, Serdar Yeşilyurt, Dmitry Tikhomirov, Christof Vockenhuber, Marcus Christl, Naki Akçar, and Fritz Schlunegger
Earth Surf. Dynam., 8, 637–659, https://doi.org/10.5194/esurf-8-637-2020, https://doi.org/10.5194/esurf-8-637-2020, 2020
Philippos Garefalakis and Fritz Schlunegger
Solid Earth, 10, 2045–2072, https://doi.org/10.5194/se-10-2045-2019, https://doi.org/10.5194/se-10-2045-2019, 2019
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The controls on the 20 Myr old Burdigalian transgression in the Swiss Molasse basin have been related to a reduction in sediment flux, a rise in global sea level, or tectonic processes in the adjacent Alps. Here, we readdress this problem and extract stratigraphic signals from the Upper Marine Molasse deposits in Switzerland. In conclusion, we consider rollback tectonics to be the main driving force controlling the transgression, which is related to a deepening and widening of the basin.
François Clapuyt, Veerle Vanacker, Marcus Christl, Kristof Van Oost, and Fritz Schlunegger
Solid Earth, 10, 1489–1503, https://doi.org/10.5194/se-10-1489-2019, https://doi.org/10.5194/se-10-1489-2019, 2019
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Using state-of-the-art geomorphic techniques, we quantified a 2-order of magnitude discrepancy between annual, decadal, and millennial sediment fluxes of a landslide-affected mountainous river catchment in the Swiss Alps. Our results illustrate that the impact of a single sediment pulse is strongly attenuated at larger spatial and temporal scales by sediment transport. The accumulation of multiple sediment pulses has rather a measurable impact on the regional pattern of sediment fluxes.
Samuel Mock, Christoph von Hagke, Fritz Schlunegger, István Dunkl, and Marco Herwegh
Solid Earth Discuss., https://doi.org/10.5194/se-2019-56, https://doi.org/10.5194/se-2019-56, 2019
Revised manuscript not accepted
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Based on own and published age data, we can infer tectonic pulses along-strike the entire northern rim of the Central Alps between 12–4 million years. Although lithologic variations largely influence the local deformation pattern, the tectonic signal is remarkably consistent all the way from Lake Geneva to Salzburg. This might result from a deep-seated tectonic force and marks a change from dominantly vertical to large-scale horizontal tectonics in the late stage of Alpine orogeny.
Alessandro Lechmann, David Mair, Akitaka Ariga, Tomoko Ariga, Antonio Ereditato, Ryuichi Nishiyama, Ciro Pistillo, Paola Scampoli, Fritz Schlunegger, and Mykhailo Vladymyrov
Solid Earth, 9, 1517–1533, https://doi.org/10.5194/se-9-1517-2018, https://doi.org/10.5194/se-9-1517-2018, 2018
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Muon tomography is a technology, similar to X-ray tomography, to image the interior of an object, including geologically interesting ones. In this work, we examined the influence of rock composition on the physical measurements, and the possible error that is made by assuming a too-simplistic rock model. We performed numerical simulations for a more realistic rock model and found that beyond 300 m of rock, the composition starts to play a significant role and has to be accounted for.
David Mair, Alessandro Lechmann, Marco Herwegh, Lukas Nibourel, and Fritz Schlunegger
Solid Earth, 9, 1099–1122, https://doi.org/10.5194/se-9-1099-2018, https://doi.org/10.5194/se-9-1099-2018, 2018
Fritz Schlunegger and Philippos Garefalakis
Earth Surf. Dynam., 6, 743–761, https://doi.org/10.5194/esurf-6-743-2018, https://doi.org/10.5194/esurf-6-743-2018, 2018
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Clast imbrication, which is a depositional fabric where clasts overlap each other similar to a run of toppled dominoes, is one of the most conspicuous sedimentary structures in coarse-grained fluvial deposits. However, the conditions leading to this fabric have been contested. Here, we calculate the hydrological conditions for various stream gradients. We find that clast imbrication most likely forms where channel gradients exceed a threshold and where upper flow regime conditions prevail.
Anna Costa, Peter Molnar, Laura Stutenbecker, Maarten Bakker, Tiago A. Silva, Fritz Schlunegger, Stuart N. Lane, Jean-Luc Loizeau, and Stéphanie Girardclos
Hydrol. Earth Syst. Sci., 22, 509–528, https://doi.org/10.5194/hess-22-509-2018, https://doi.org/10.5194/hess-22-509-2018, 2018
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We explore the signal of a warmer climate in the suspended-sediment dynamics of a regulated and human-impacted Alpine catchment. We demonstrate that temperature-driven enhanced melting of glaciers, which occurred in the mid-1980s, played a dominant role in suspended sediment concentration rise, through increased runoff from sediment-rich proglacial areas, increased contribution of sediment-rich meltwater, and increased sediment supply in proglacial areas due to glacier recession.
François Clapuyt, Veerle Vanacker, Fritz Schlunegger, and Kristof Van Oost
Earth Surf. Dynam., 5, 791–806, https://doi.org/10.5194/esurf-5-791-2017, https://doi.org/10.5194/esurf-5-791-2017, 2017
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This work aims at understanding the behaviour of an earth flow located in the Swiss Alps by reconstructing very accurately its topography over a 2-year period. Aerial photos taken from a drone, which are then processed using a computer vision algorithm, were used to derive the topographic datasets. Combination and careful interpretation of high-resolution topographic analyses reveal the internal mechanisms of the earthflow and its complex rotational structure, which is evolving over time.
Laura Stutenbecker, Anna Costa, and Fritz Schlunegger
Earth Surf. Dynam., 4, 253–272, https://doi.org/10.5194/esurf-4-253-2016, https://doi.org/10.5194/esurf-4-253-2016, 2016
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This paper considers the influence of lithology on the landscape development in the Central Swiss Alps. In high-alpine settings such as the upper Rhône valley, external forcing by climate, glaciation and uplift affects the geomorphological evolution of the landscape. By careful compilation of published data and geomorphological analysis we found that the rock type and its susceptibility to erosion are the main factors controlling the response time to those perturbations.
K. P. Norton, F. Schlunegger, and C. Litty
Earth Surf. Dynam., 4, 147–157, https://doi.org/10.5194/esurf-4-147-2016, https://doi.org/10.5194/esurf-4-147-2016, 2016
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Cut-fill terraces are common landforms throughout the world. Their distribution both in space and time is not clear-cut, as they can arise from numerous processes. We apply a climate-dependent regolith production algorithm to determine potential sediment loads during climate shifts. When combined with transport capacity, our results suggest that the cut-fill terraces of western Peru can result from transient stripping of hillslope sediment but not steady-state hillslope erosion.
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Earth Surf. Dynam., 12, 1205–1226, https://doi.org/10.5194/esurf-12-1205-2024, https://doi.org/10.5194/esurf-12-1205-2024, 2024
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Barchans are fast-moving sand dunes which form large populations (swarms) on Earth and Mars. We show that a small range of model parameters produces swarms in which dune size does not vary downwind – something that is observed in nature but not when using earlier models. We also show how the shape of dunes and the spatial patterns they form are affected by wind direction. This work furthers our understanding of the interplay between environmental drivers, dune interactions, and swarm properties.
Jeffrey Keck, Erkan Istanbulluoglu, Benjamin Campforts, Gregory Tucker, and Alexander Horner-Devine
Earth Surf. Dynam., 12, 1165–1191, https://doi.org/10.5194/esurf-12-1165-2024, https://doi.org/10.5194/esurf-12-1165-2024, 2024
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MassWastingRunout (MWR) is a new landslide runout model designed for sediment transport, landscape evolution, and hazard assessment applications. MWR is written in Python and includes a calibration utility that automatically determines best-fit parameters for a site and empirical probability density functions of each parameter for probabilistic model implementation. MWR and Jupyter Notebook tutorials are available as part of the Landlab package at https://github.com/landlab/landlab.
Ariane Mueting and Bodo Bookhagen
Earth Surf. Dynam., 12, 1121–1143, https://doi.org/10.5194/esurf-12-1121-2024, https://doi.org/10.5194/esurf-12-1121-2024, 2024
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This study investigates the use of optical PlanetScope data for offset tracking of the Earth's surface movement. We found that co-registration accuracy is locally degraded when outdated elevation models are used for orthorectification. To mitigate this bias, we propose to only correlate scenes acquired from common perspectives or base orthorectification on more up-to-date elevation models generated from PlanetScope data alone. This enables a more detailed analysis of landslide dynamics.
Cho-Hee Lee, Yeong Bae Seong, John Weber, Sangmin Ha, Dong-Eun Kim, and Byung Yong Yu
Earth Surf. Dynam., 12, 1091–1120, https://doi.org/10.5194/esurf-12-1091-2024, https://doi.org/10.5194/esurf-12-1091-2024, 2024
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Topographic metrics were used to understand changes due to tectonic activity. We evaluated the relative tectonic activity along the Ulsan Fault Zone (UFZ), one of the most active fault zones in South Korea. We divided the UFZ into five segments, based on the spatial variation in activity. We modeled the landscape evolution of the study area and interpreted tectono-geomorphic history during which the northern part of the UFZ experienced asymmetric uplift, while the southern part did not.
Juditha Aga, Livia Piermattei, Luc Girod, Kristoffer Aalstad, Trond Eiken, Andreas Kääb, and Sebastian Westermann
Earth Surf. Dynam., 12, 1049–1070, https://doi.org/10.5194/esurf-12-1049-2024, https://doi.org/10.5194/esurf-12-1049-2024, 2024
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Coastal rock cliffs on Svalbard are considered to be fairly stable; however, long-term trends in coastal-retreat rates remain unknown. This study examines changes in the coastline position along Brøggerhalvøya, Svalbard, using aerial images from 1970, 1990, 2010, and 2021. Our analysis shows that coastal-retreat rates accelerate during the period 2010–2021, which coincides with increasing storminess and retreating sea ice.
Aaron T. Steelquist, Gustav B. Seixas, Mary L. Gillam, Sourav Saha, Seulgi Moon, and George E. Hilley
Earth Surf. Dynam., 12, 1071–1089, https://doi.org/10.5194/esurf-12-1071-2024, https://doi.org/10.5194/esurf-12-1071-2024, 2024
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The rates at which rivers erode their bed can be used to interpret the geologic history of a region. However, these rates depend significantly on the time window over which you measure. We use multiple dating methods to determine an incision rate for the San Juan River and compare it to regional rates with longer timescales. We demonstrate how specific geologic events, such as cutoffs of bedrock meander bends, are likely to preserve material we can date but also bias the rates we measure.
Johannes Leinauer, Michael Dietze, Sibylle Knapp, Riccardo Scandroglio, Maximilian Jokel, and Michael Krautblatter
Earth Surf. Dynam., 12, 1027–1048, https://doi.org/10.5194/esurf-12-1027-2024, https://doi.org/10.5194/esurf-12-1027-2024, 2024
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Massive rock slope failures are a significant alpine hazard and change the Earth's surface. Therefore, we must understand what controls the preparation of such events. By correlating 4 years of slope displacements with meteorological and seismic data, we found that water from rain and snowmelt is the most important driver. Our approach is applicable to similar sites and indicates where future climatic changes, e.g. in rain intensity and frequency, may alter the preparation of slope failure.
Julien Coatléven and Benoit Chauveau
Earth Surf. Dynam., 12, 995–1026, https://doi.org/10.5194/esurf-12-995-2024, https://doi.org/10.5194/esurf-12-995-2024, 2024
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The aim of this paper is to explain how to incorporate classical water flow routines into landscape evolution models while keeping numerical errors under control. The key idea is to adapt filtering strategies to eliminate anomalous numerical errors and mesh dependencies, as confirmed by convergence tests with analytic solutions. The emergence of complex geomorphic structures is now driven exclusively by nonlinear heterogeneous physical processes rather than by random numerical artifacts.
Jingjuan Li, John D. Jansen, Xuanmei Fan, Zhiyong Ding, Shugang Kang, and Marco Lovati
Earth Surf. Dynam., 12, 953–971, https://doi.org/10.5194/esurf-12-953-2024, https://doi.org/10.5194/esurf-12-953-2024, 2024
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In this study, we investigated the geomorphology, sedimentology, and chronology of Tuanjie (seven terraces) and Taiping (three terraces) terraces in Diexi, eastern Tibetan Plateau. Results highlight that two damming and three outburst events occurred in the area during the late Pleistocene, and the outburst floods have been a major factor in the formation of tectonically active mountainous river terraces. Tectonic activity and climatic changes play a minor role.
Andrew Hollyday, Maureen E. Raymo, Jacqueline Austermann, Fred Richards, Mark Hoggard, and Alessio Rovere
Earth Surf. Dynam., 12, 883–905, https://doi.org/10.5194/esurf-12-883-2024, https://doi.org/10.5194/esurf-12-883-2024, 2024
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Sea level was significantly higher during the Pliocene epoch, around 3 million years ago. The present-day elevations of shorelines that formed in the past provide a data constraint on the extent of ice sheet melt and the global sea level response under warm Pliocene conditions. In this study, we identify 10 escarpments that formed from wave-cut erosion during Pliocene times and compare their elevations with model predictions of solid Earth deformation processes to estimate past sea level.
Gregory A. Ruetenik, Ken L. Ferrier, and Odin Marc
Earth Surf. Dynam., 12, 863–881, https://doi.org/10.5194/esurf-12-863-2024, https://doi.org/10.5194/esurf-12-863-2024, 2024
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Fluvial sediment fluxes increased dramatically in Taiwan during Typhoon Morakot in 2009, which produced some of the heaviest landsliding on record. We analyzed fluvial discharge and suspended sediment concentration data at 87 gauging stations across Taiwan to quantify fluvial sediment responses since Morakot. In basins heavily impacted by landsliding, rating curve coefficients sharply increased during Morakot and then declined exponentially with a characteristic decay time of <10 years.
Nil Carrion-Bertran, Albert Falqués, Francesca Ribas, Daniel Calvete, Rinse de Swart, Ruth Durán, Candela Marco-Peretó, Marta Marcos, Angel Amores, Tim Toomey, Àngels Fernández-Mora, and Jorge Guillén
Earth Surf. Dynam., 12, 819–839, https://doi.org/10.5194/esurf-12-819-2024, https://doi.org/10.5194/esurf-12-819-2024, 2024
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The sensitivity to the wave and sea-level forcing sources in predicting a 6-month embayed beach evolution is assessed using two different morphodynamic models. After a successful model calibration using in situ data, other sources are applied. The wave source choice is critical: hindcast data provide wrong results due to an angle bias, whilst the correct dynamics are recovered with the wave conditions from an offshore buoy. The use of different sea-level sources gives no significant differences.
Thomas J. Barnes, Thomas V. Schuler, Simon Filhol, and Karianne S. Lilleøren
Earth Surf. Dynam., 12, 801–818, https://doi.org/10.5194/esurf-12-801-2024, https://doi.org/10.5194/esurf-12-801-2024, 2024
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In this paper, we use machine learning to automatically outline landforms based on their characteristics. We test several methods to identify the most accurate and then proceed to develop the most accurate to improve its accuracy further. We manage to outline landforms with 65 %–75 % accuracy, at a resolution of 10 m, thanks to high-quality/high-resolution elevation data. We find that it is possible to run this method at a country scale to quickly produce landform inventories for future studies.
Fritz Schlunegger, Edi Kissling, Dimitri Tibo Bandou, Guilhem Amin Douillet, David Mair, Urs Marti, Regina Reber, Patrick Fabian Schläfli, and Michael Alfred Schwenk
EGUsphere, https://doi.org/10.5194/egusphere-2024-683, https://doi.org/10.5194/egusphere-2024-683, 2024
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Overdeepenings are bedrock depressions filled with sediment. We combine the results of a gravity survey with drilling data to explore the morphology of such a depression beneath the city of Bern. We find that the target overdeepening comprises two basins >200 m deep. They are separated by a bedrock riegel that itself is cut by narrow canyons up to 150 m deep. We postulate that these structures formed underneath a glacier, where erosion by subglacial meltwater caused the formation of the canyons.
Eric Petersen, Regine Hock, and Michael G. Loso
Earth Surf. Dynam., 12, 727–745, https://doi.org/10.5194/esurf-12-727-2024, https://doi.org/10.5194/esurf-12-727-2024, 2024
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Ice cliffs are melt hot spots that increase melt rates on debris-covered glaciers which otherwise see a reduction in melt rates. In this study, we show how surface runoff streams contribute to the generation, evolution, and survival of ice cliffs by carving into the glacier and transporting rocky debris. On Kennicott Glacier, Alaska, 33 % of ice cliffs are actively influenced by streams, while nearly half are within 10 m of streams.
Daniel O'Hara, Liran Goren, Roos M. J. van Wees, Benjamin Campforts, Pablo Grosse, Pierre Lahitte, Gabor Kereszturi, and Matthieu Kervyn
Earth Surf. Dynam., 12, 709–726, https://doi.org/10.5194/esurf-12-709-2024, https://doi.org/10.5194/esurf-12-709-2024, 2024
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Understanding how volcanic edifices develop drainage basins remains unexplored in landscape evolution. Using digital evolution models of volcanoes with varying ages, we quantify the geometries of their edifices and associated drainage basins through time. We find that these metrics correlate with edifice age and are thus useful indicators of a volcano’s history. We then develop a generalized model for how volcano basins develop and compare our results to basin evolution in other settings.
Brayden Noh, Omar Wani, Kieran B. J. Dunne, and Michael P. Lamb
Earth Surf. Dynam., 12, 691–708, https://doi.org/10.5194/esurf-12-691-2024, https://doi.org/10.5194/esurf-12-691-2024, 2024
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In this paper, we propose a framework for generating risk maps that provide the probabilities of erosion due to river migration. This framework uses concepts from probability theory to learn the river migration model's parameter values from satellite data while taking into account parameter uncertainty. Our analysis shows that such geomorphic risk estimation is more reliable than models that do not explicitly consider various sources of variability and uncertainty.
Steven Y. J. Lai, David Amblas, Aaron Micallef, and Hervé Capart
Earth Surf. Dynam., 12, 621–640, https://doi.org/10.5194/esurf-12-621-2024, https://doi.org/10.5194/esurf-12-621-2024, 2024
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This study explores the creation of submarine canyons and hanging-wall fans on active faults, which can be defined by gravity-dominated breaching and underflow-dominated diffusion processes. The study reveals the self-similarity in canyon–fan long profiles, uncovers Hack’s scaling relationship and proposes a formula to estimate fan volume using canyon length. This is validated by global data from source-to-sink systems, providing insights into deep-water sedimentary processes.
Anuska Narayanan, Sagy Cohen, and John R. Gardner
Earth Surf. Dynam., 12, 581–599, https://doi.org/10.5194/esurf-12-581-2024, https://doi.org/10.5194/esurf-12-581-2024, 2024
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This study investigates the profound impact of deforestation in the Amazon on sediment dynamics. Novel remote sensing data and statistical analyses reveal significant changes, especially in heavily deforested regions, with rapid effects within a year. In less disturbed areas, a 1- to 2-year lag occurs, influenced by natural sediment shifts and human activities. These findings highlight the need to understand the consequences of human activity for our planet's future.
Jacob Hardt, Tim P. Dooley, and Michael R. Hudec
Earth Surf. Dynam., 12, 559–579, https://doi.org/10.5194/esurf-12-559-2024, https://doi.org/10.5194/esurf-12-559-2024, 2024
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We investigate the reaction of salt structures on ice sheet transgressions. We used a series of sandbox models that enabled us to experiment with scaled-down versions of salt bodies from northern Germany. The strongest reactions occurred when large salt pillows were partly covered by the ice load. Subsurface salt structures may play an important role in the energy transition, e.g., as energy storage. Thus, it is important to understand all processes that affect their stability.
Prakash Pokhrel, Mikael Attal, Hugh D. Sinclair, Simon M. Mudd, and Mark Naylor
Earth Surf. Dynam., 12, 515–536, https://doi.org/10.5194/esurf-12-515-2024, https://doi.org/10.5194/esurf-12-515-2024, 2024
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Pebbles become increasingly rounded during downstream transport in rivers due to abrasion. This study quantifies pebble roundness along the length of two Himalayan rivers. We demonstrate that roundness increases with downstream distance and that the rates are dependent on rock type. We apply this to reconstructing travel distances and hence the size of ancient Himalaya. Results show that the ancient river network was larger than the modern one, indicating that there has been river capture.
Hayden L. Jacobson, Danica L. Roth, Gabriel Walton, Margaret Zimmer, and Kerri Johnson
EGUsphere, https://doi.org/10.5194/egusphere-2023-2694, https://doi.org/10.5194/egusphere-2023-2694, 2024
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Loose grains travel farther after a fire because no vegetation is left to stop them. This matters since loose grains at the base of a slope can turn into a debris flow if it rains. To find if grass growing back after a fire had different impacts on grains of different sizes on slopes of different steepness, we dropped thousands of natural grains and measured how far they went. Large grains went farther 7 months after the fire than 11 months after, and small grain movement didn’t change much.
Elizabeth Orr, Taylor Schildgen, Stefanie Tofelde, Hella Wittmann, and Ricardo Alonso
EGUsphere, https://doi.org/10.5194/egusphere-2024-784, https://doi.org/10.5194/egusphere-2024-784, 2024
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Fluvial terraces and alluvial fans in the Toro Basin, NW Argentina record river evolution and global climate cycles over time. Landform dating reveals lower-frequency climate cycles (100-kyr) preserved downstream and higher-frequency cycles (21/40-kyr) upstream, supporting theoretical predications that longer rivers filter out higher-frequency climate signals. This finding improves our understanding of the spatial distribution of sedimentary paleoclimate records within landscapes.
Orie Cecil, Nicholas Cohn, Matthew Farthing, Sourav Dutta, and Andrew Trautz
EGUsphere, https://doi.org/10.5194/egusphere-2024-855, https://doi.org/10.5194/egusphere-2024-855, 2024
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Using computational fluid dynamics, we analyze the error trends of an analytical shear stress distribution model used to drive aeolian transport for coastal dunes which are an important line of defense against storm related flooding hazards. We find that compared to numerical simulations, the analytical model results in a net overprediction of the landward migration rate. Additionally, two data-driven approaches are proposed for reducing the error while maintaining computational efficiency.
Jens Martin Turowski, Aaron Bufe, and Stefanie Tofelde
Earth Surf. Dynam., 12, 493–514, https://doi.org/10.5194/esurf-12-493-2024, https://doi.org/10.5194/esurf-12-493-2024, 2024
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Fluvial valleys are ubiquitous landforms, and understanding their formation and evolution affects a wide range of disciplines from archaeology and geology to fish biology. Here, we develop a model to predict the width of fluvial valleys for a wide range of geographic conditions. In the model, fluvial valley width is controlled by the two competing factors of lateral channel mobility and uplift. The model complies with available data and yields a broad range of quantitative predictions.
Daniel J. Ciarletta, Jennifer L. Miselis, Julie C. Bernier, and Arnell S. Forde
Earth Surf. Dynam., 12, 449–475, https://doi.org/10.5194/esurf-12-449-2024, https://doi.org/10.5194/esurf-12-449-2024, 2024
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We reconstructed the evolution of Fire Island, a barrier island in New York, USA, to identify drivers of landscape change. Results reveal Fire Island was once divided into multiple inlet-separated islands with distinct features. Later, inlets closed, and Fire Island’s landscape became more uniform as human activities intensified. The island is now less mobile and less likely to resist and recover from storm impacts and sea level rise. This vulnerability may exist for other stabilized barriers.
Chao Zhou, Xibin Tan, Yiduo Liu, and Feng Shi
Earth Surf. Dynam., 12, 433–448, https://doi.org/10.5194/esurf-12-433-2024, https://doi.org/10.5194/esurf-12-433-2024, 2024
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The drainage-divide stability provides new insights into both the river network evolution and the tectonic and/or climatic changes. Several methods have been proposed to determine the direction of drainage-divide migration. However, how to quantify the migration rate of drainage divides remains challenging. In this paper, we propose a new method to calculate the migration rate of drainage divides from high-resolution topographic data.
Justin A. Nghiem, Gen K. Li, Joshua P. Harringmeyer, Gerard Salter, Cédric G. Fichot, Luca Cortese, and Michael P. Lamb
EGUsphere, https://doi.org/10.5194/egusphere-2024-524, https://doi.org/10.5194/egusphere-2024-524, 2024
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Fine sediment grains in freshwater can cohere into faster settling particles called flocs, but floc settling velocity theory has not been fully validated. Data from the Wax Lake Delta verify a semi-empirical model relying on turbulence and geochemical factors. We showed that the representative grain diameter within flocs relies on floc structure and that floc internal flow follows a model in which flocs consist of permeable grain clusters, thus improving a physics-based settling velocity model.
Moritz Altmann, Madlene Pfeiffer, Florian Haas, Jakob Rom, Fabian Fleischer, Tobias Heckmann, Livia Piermattei, Michael Wimmer, Lukas Braun, Manuel Stark, Sarah Betz-Nutz, and Michael Becht
Earth Surf. Dynam., 12, 399–431, https://doi.org/10.5194/esurf-12-399-2024, https://doi.org/10.5194/esurf-12-399-2024, 2024
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We show a long-term erosion monitoring of several sections on Little Ice Age lateral moraines with derived sediment yield from historical and current digital elevation modelling (DEM)-based differences. The first study period shows a clearly higher range of variability of sediment yield within the sites than the later periods. In most cases, a decreasing trend of geomorphic activity was observed.
Paul A. Carling
Earth Surf. Dynam., 12, 381–397, https://doi.org/10.5194/esurf-12-381-2024, https://doi.org/10.5194/esurf-12-381-2024, 2024
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Edge rounding in Shap granite glacial erratics is an irregular function of distance from the source outcrop in northern England, UK. Block shape is conservative, evolving according to block fracture mechanics – stochastic and silver ratio models – towards either of two attractor states. Progressive reduction in size occurs for blocks transported at the sole of the ice mass where the blocks are subject to compressive and tensile forces of the ice acting against a bedrock or till surface.
Stefan Hergarten
EGUsphere, https://doi.org/10.5194/egusphere-2024-336, https://doi.org/10.5194/egusphere-2024-336, 2024
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Faceted topographies are impressing footprints of active tectonics in geomorphology. This paper investigates the evolution of faceted topographies at normal faults and its interaction with the river network theoretically and numerically. As a main result beyond several relations for the the geometry of facets, the horizontal displacement associated to normal faults is crucial for the dissection of initially polygonal facets into triangular facets bounded by almost parallel rivers.
Gary Parker, Chenge An, Michael P. Lamb, Marcelo H. Garcia, Elizabeth H. Dingle, and Jeremy G. Venditti
Earth Surf. Dynam., 12, 367–380, https://doi.org/10.5194/esurf-12-367-2024, https://doi.org/10.5194/esurf-12-367-2024, 2024
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River morphology has traditionally been divided by the size 2 mm. We use dimensionless arguments to show that particles in the 1–5 mm range (i) are the finest range not easily suspended by alluvial flood flows, (ii) are transported preferentially over coarser gravel, and (iii), within limits, are also transported preferentially over sand. We show how fluid viscosity mediates the special status of sediment in this range.
Lindsay Marie Capito, Enrico Pandrin, Walter Bertoldi, Nicola Surian, and Simone Bizzi
Earth Surf. Dynam., 12, 321–345, https://doi.org/10.5194/esurf-12-321-2024, https://doi.org/10.5194/esurf-12-321-2024, 2024
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We propose that the pattern of erosion and deposition from repeat topographic surveys can be a proxy for path length in gravel-bed rivers. With laboratory and field data, we applied tools from signal processing to quantify this periodicity and used these path length estimates to calculate sediment transport using the morphological method. Our results highlight the potential to expand the use of the morphological method using only remotely sensed data as well as its limitations.
Xuxu Wu, Jonathan Malarkey, Roberto Fernández, Jaco H. Baas, Ellen Pollard, and Daniel R. Parsons
Earth Surf. Dynam., 12, 231–247, https://doi.org/10.5194/esurf-12-231-2024, https://doi.org/10.5194/esurf-12-231-2024, 2024
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The seabed changes from flat to rippled in response to the frictional influence of waves and currents. This experimental study has shown that the speed of this change, the size of ripples that result and even whether ripples appear also depend on the amount of sticky mud present. This new classification on the basis of initial mud content should lead to improvements in models of seabed change in present environments by engineers and the interpretation of past environments by geologists.
Andrea D'Alpaos, Davide Tognin, Laura Tommasini, Luigi D'Alpaos, Andrea Rinaldo, and Luca Carniello
Earth Surf. Dynam., 12, 181–199, https://doi.org/10.5194/esurf-12-181-2024, https://doi.org/10.5194/esurf-12-181-2024, 2024
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Sediment erosion induced by wind waves is one of the main drivers of the morphological evolution of shallow tidal environments. However, a reliable description of erosion events for the long-term morphodynamic modelling of tidal systems is still lacking. By statistically characterizing sediment erosion dynamics in the Venice Lagoon over the last 4 centuries, we set up a novel framework for a synthetic, yet reliable, description of erosion events in tidal systems.
Davide Tognin, Andrea D'Alpaos, Luigi D'Alpaos, Andrea Rinaldo, and Luca Carniello
Earth Surf. Dynam., 12, 201–218, https://doi.org/10.5194/esurf-12-201-2024, https://doi.org/10.5194/esurf-12-201-2024, 2024
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Reliable quantification of sediment transport processes is necessary to understand the fate of shallow tidal environments. Here we present a framework for the description of suspended sediment dynamics to quantify deposition in the long-term modelling of shallow tidal systems. This characterization, together with that of erosion events, allows one to set up synthetic, yet reliable, models for the long-term evolution of tidal landscapes.
Emma L. S. Graf, Hugh D. Sinclair, Mikaël Attal, Boris Gailleton, Basanta Raj Adhikari, and Bishnu Raj Baral
Earth Surf. Dynam., 12, 135–161, https://doi.org/10.5194/esurf-12-135-2024, https://doi.org/10.5194/esurf-12-135-2024, 2024
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Using satellite images, we show that, unlike other examples of earthquake-affected rivers, the rivers of central Nepal experienced little increase in sedimentation following the 2015 Gorkha earthquake. Instead, a catastrophic flood occurred in 2021 that buried towns and agricultural land under up to 10 m of sediment. We show that intense storms remobilised glacial sediment from high elevations causing much a greater impact than flushing of earthquake-induced landslides.
Mohamad Nasr, Adele Johannot, Thomas Geay, Sebastien Zanker, Jules Le Guern, and Alain Recking
Earth Surf. Dynam., 12, 117–134, https://doi.org/10.5194/esurf-12-117-2024, https://doi.org/10.5194/esurf-12-117-2024, 2024
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Hydrophones are used to monitor sediment transport in the river by listening to the acoustic noise generated by particle impacts on the riverbed. However, this acoustic noise is modified by the river flow and can cause misleading information about sediment transport. This article proposes a model that corrects the measured acoustic signal. Testing the model showed that the corrected signal is better correlated with bedload flux in the river.
Jessica Laible, Guillaume Dramais, Jérôme Le Coz, Blaise Calmel, Benoît Camenen, David J. Topping, William Santini, Gilles Pierrefeu, and François Lauters
EGUsphere, https://doi.org/10.5194/egusphere-2023-2348, https://doi.org/10.5194/egusphere-2023-2348, 2024
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Suspended-sand fluxes in rivers vary with time and space, complicating their measurement. The proposed method captures the vertical and lateral variations of suspended-sand concentration throughout a river cross section. It merges water samples taken at various positions throughout the cross section with high-resolution acoustic velocity and discharge measurements. The method also determines the sand flux uncertainty and can be easily applied to other sites using the available open-source code.
Byungho Kang, Rusty A. Feagin, Thomas Huff, and Orencio Durán Vinent
Earth Surf. Dynam., 12, 105–115, https://doi.org/10.5194/esurf-12-105-2024, https://doi.org/10.5194/esurf-12-105-2024, 2024
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We provide a detailed characterization of the frequency, intensity and duration of flooding events at a site along the Texas coast. Our analysis demonstrates the suitability of relatively simple wave run-up models to estimate the frequency and intensity of coastal flooding. Our results validate and expand a probabilistic model of coastal flooding driven by wave run-up that can then be used in coastal risk management in response to sea level rise.
Shunsuke Oya, Fumitoshi Imaizumi, and Shoki Takayama
Earth Surf. Dynam., 12, 67–86, https://doi.org/10.5194/esurf-12-67-2024, https://doi.org/10.5194/esurf-12-67-2024, 2024
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The monitoring of pore water pressure in fully and partly saturated debris flows was performed at Ohya landslide scar, central Japan. The pore water pressure in some partly saturated flows greatly exceeded the hydrostatic pressure. The depth gradient of the pore water pressure in the lower part of the flow was generally higher than the upper part of the flow. We conclude that excess pore water pressure is present in many debris flow surges and is an important mechanism in debris flow behavior.
Gabriele Barile, Marco Redolfi, and Marco Tubino
Earth Surf. Dynam., 12, 87–103, https://doi.org/10.5194/esurf-12-87-2024, https://doi.org/10.5194/esurf-12-87-2024, 2024
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River bifurcations often show the closure of one branch (avulsion), whose causes are still poorly understood. Our model shows that when one branch stops transporting sediments, the other considerably erodes and captures much more flow, resulting in a self-sustaining process. This phenomenon intensifies when increasing the length of the branches, eventually leading to branch closure. This work may help to understand when avulsions occur and thus to design sustainable river restoration projects.
Dieter Rickenmann
Earth Surf. Dynam., 12, 11–34, https://doi.org/10.5194/esurf-12-11-2024, https://doi.org/10.5194/esurf-12-11-2024, 2024
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Field measurements of the bedload flux with a high temporal resolution in a steep mountain stream were used to analyse the transport fluctuations as a function of the flow conditions. The disequilibrium ratio, a proxy for the solid particle concentration in the flow, was found to influence the sediment transport behaviour, and above-average disequilibrium conditions – associated with a larger sediment availability on the streambed – substantially affect subsequent transport conditions.
Byungho Kang, Rusty A. Feagin, Thomas Huff, and Orencio Durán Vinent
Earth Surf. Dynam., 12, 1–10, https://doi.org/10.5194/esurf-12-1-2024, https://doi.org/10.5194/esurf-12-1-2024, 2024
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Coastal flooding can cause significant damage to coastal ecosystems, infrastructure, and communities and is expected to increase in frequency with the acceleration of sea level rise. In order to respond to it, it is crucial to measure and model their frequency and intensity. Here, we show deep-learning techniques can be successfully used to automatically detect flooding events from complex coastal imagery, opening the way to real-time monitoring and data acquisition for model development.
Judith Y. Zomer, Bart Vermeulen, and Antonius J. F. Hoitink
Earth Surf. Dynam., 11, 1283–1298, https://doi.org/10.5194/esurf-11-1283-2023, https://doi.org/10.5194/esurf-11-1283-2023, 2023
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Secondary bedforms that are superimposed on large, primary dunes likely play a large role in fluvial systems. This study demonstrates that they can be omnipresent. Especially during peak flows, they grow large and can have steep slopes, likely affecting flood risk and sediment transport dynamics. Primary dune morphology determines whether they continuously or intermittently migrate. During discharge peaks, the secondary bedforms can become the dominant dune scale.
Matthew C. Morriss, Benjamin Lehmann, Benjamin Campforts, George Brencher, Brianna Rick, Leif S. Anderson, Alexander L. Handwerger, Irina Overeem, and Jeffrey Moore
Earth Surf. Dynam., 11, 1251–1274, https://doi.org/10.5194/esurf-11-1251-2023, https://doi.org/10.5194/esurf-11-1251-2023, 2023
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In this paper, we investigate the 28 June 2022 collapse of the Chaos Canyon landslide in Rocky Mountain National Park, Colorado, USA. We find that the landslide was moving prior to its collapse and took place at peak spring snowmelt; temperature modeling indicates the potential presence of permafrost. We hypothesize that this landslide could be part of the broader landscape evolution changes to alpine terrain caused by a warming climate, leading to thawing alpine permafrost.
Christopher Tomsett and Julian Leyland
Earth Surf. Dynam., 11, 1223–1249, https://doi.org/10.5194/esurf-11-1223-2023, https://doi.org/10.5194/esurf-11-1223-2023, 2023
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Vegetation influences how rivers change through time, yet the way in which we analyse vegetation is limited. Current methods collect detailed data at the individual plant level or determine dominant vegetation types across larger areas. Herein, we use UAVs to collect detailed vegetation datasets for a 1 km length of river and link vegetation properties to channel evolution occurring within the study site, providing a new method for investigating the influence of vegetation on river systems.
Rabab Yassine, Ludovic Cassan, Hélène Roux, Olivier Frysou, and François Pérès
Earth Surf. Dynam., 11, 1199–1221, https://doi.org/10.5194/esurf-11-1199-2023, https://doi.org/10.5194/esurf-11-1199-2023, 2023
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Predicting river morphology evolution is very complicated, especially for mountain rivers with complex morphologies such as the Lac des Gaves reach in France. A 2D hydromorphological model was developed to reproduce the channel's evolution and provide reliable volumetric predictions while revealing the challenge of choosing adapted sediment transport and friction laws. Our model can provide decision-makers with reliable predictions to design suitable restoration measures for this reach.
Daisuke Harada and Shinji Egashira
Earth Surf. Dynam., 11, 1183–1197, https://doi.org/10.5194/esurf-11-1183-2023, https://doi.org/10.5194/esurf-11-1183-2023, 2023
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This paper proposes a method for describing large-wood behavior in terms of the convection equation and the storage equation, which are associated with active sediment erosion and deposition. Compared to the existing Lagrangian method, the proposed method can easily simulate the behavior of large wood in the flow field with active sediment transport. The method is applied to the flood disaster in the Akatani River in 2017, and the 2-D flood flow computations are successfully performed.
Hemanti Sharma and Todd A. Ehlers
Earth Surf. Dynam., 11, 1161–1181, https://doi.org/10.5194/esurf-11-1161-2023, https://doi.org/10.5194/esurf-11-1161-2023, 2023
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Seasonality in precipitation (P) and vegetation (V) influences catchment erosion (E), although which factor plays the dominant role is unclear. In this study, we performed a sensitivity analysis of E to P–V seasonality through numerical modeling. Our results suggest that P variations strongly influence seasonal variations in E, while the effect of seasonal V variations is secondary but significant. This is more pronounced in moderate and least pronounced in extreme environmental settings.
Cited articles
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Short summary
This paper focuses on the analysis of the properties controlling the grain size in the streams of the western Peruvian Andes. Pebble size distributions in these streams have been compared to fluvial processes and basin properties. The resulting trends and differences in sediment properties seem to have been controlled by threshold conditions upon supply and transport.
This paper focuses on the analysis of the properties controlling the grain size in the streams...
