Implications of sediment-flux-dependent river incision models for landscape evolution

2002 ◽  
Vol 107 (B2) ◽  
Author(s):  
Kelin X. Whipple
Keyword(s):  
Landscape Evolution ◽  
Sediment Flux ◽  
River Incision

New constraints on sediment-flux–dependent river incision: Implications for extracting tectonic signals from river profiles

Geology ◽  
2008 ◽  
Vol 36 (7) ◽  
pp. 535 ◽  
Author(s):  
Patience A. Cowie ◽  
Alexander C. Whittaker ◽  
Mikaël Attal ◽  
Gerald Roberts ◽  
Greg E. Tucker ◽  
...  
Keyword(s):  
Sediment Flux ◽  
River Incision ◽  
River Profiles

scholarly journals Constraining plateau uplift in southern Africa by combining thermochronology, sediment flux, topography, and landscape evolution modeling

2020 ◽  
Author(s):  
Jessica R. Stanley ◽  
Jean Braun ◽  
Guillaume Baby ◽  
François Guillocheau ◽  
Cecile Robin ◽  
...  
Keyword(s):  
Southern Africa ◽  
Landscape Evolution ◽  
Sediment Flux ◽  
Plateau Uplift ◽  
Evolution Modeling

scholarly journals Landscape evolution models using the stream power incision model show unrealistic behavior when <i>m</i> ∕ <i>n</i> equals 0.5

2017 ◽  
Vol 5 (4) ◽  
pp. 807-820 ◽  
Author(s):  
Jeffrey S. Kwang ◽  
Gary Parker
Keyword(s):  
Steady State ◽  
Landscape Evolution ◽  
Drainage Area ◽  
Uplift Rate ◽  
Stream Power ◽  
River Incision ◽  
Vertical Incision ◽  
Small Scales ◽  
Insight Into

Abstract. Landscape evolution models often utilize the stream power incision model to simulate river incision: E = KAmSn, where E is the vertical incision rate, K is the erodibility constant, A is the upstream drainage area, S is the channel gradient, and m and n are exponents. This simple but useful law has been employed with an imposed rock uplift rate to gain insight into steady-state landscapes. The most common choice of exponents satisfies m ∕ n = 0.5. Yet all models have limitations. Here, we show that when hillslope diffusion (which operates only on small scales) is neglected, the choice m ∕ n = 0.5 yields a curiously unrealistic result: the predicted landscape is invariant to horizontal stretching. That is, the steady-state landscape for a 10 km2 horizontal domain can be stretched so that it is identical to the corresponding landscape for a 1000 km2 domain.

scholarly journals Modeling Short-Term Landscape Modification and Sedimentary Budget Induced by Dam Removal: Insights from LEM Application

2020 ◽  
Vol 10 (21) ◽  
pp. 7697
Author(s):  
Dario Gioia ◽  
Marcello Schiattarella
Keyword(s):  
Landscape Evolution ◽  
Dam Removal ◽  
Sediment Flux ◽  
Short Term ◽  
Open Problems ◽  
Landscape Modification ◽  
Natural Processes ◽  
Base Level ◽  
Geomorphic Response ◽  
Fluvial Incision

Simulation scenarios of sediment flux variation and topographic changes due to dam removal have been investigated in a reservoir catchment of the axial zone of southern Italy through the application of a landscape evolution model (i.e.,: the Caesar–Lisflood landscape evolution models, LEM). LEM simulation highlights that the abrupt change in base level due to dam removal induces a significant increase in erosion ability of main channels and a strong incision of the reservoir infill. Analysis of the sediment dynamics resulting from the dam removal highlights a significant increase of the total eroded volumes in the post dam scenario of a factor higher than 4. Model results also predict a strong modification of the longitudinal profile of main channels, which promoted fluvial incision upstream and downstream of the former reservoir area. Such a geomorphic response is in agreement with previous analysis of the fluvial system short-term response induced by base-level lowering, thus demonstrating the reliability of LEM-based analysis for solving open problems in applied geomorphology such as perturbations and short-term landscape modification natural processes or human impact.

Along-stream variations in valley flank erosion rates measured using 10Be concentrations in colluvial deposits from Atacama canyons: implications for valley widening

2020 ◽  
Author(s):  
Valeria Zavala ◽  
Sebastien Carretier ◽  
Vincent Regard ◽  
Stephane Bonnet ◽  
Rodrigo Riquelme ◽  
...  
Keyword(s):  
Erosion Rate ◽  
Landscape Evolution ◽  
Sediment Flux ◽  
Lower Probability ◽  
Upward Migration ◽  
Channel Mobility ◽  
Erosion Rates ◽  
Valley Flank ◽  
Lateral Erosion ◽  
Bed Slope

&lt;p&gt;The downstream increase in valley width is an important feature of fluvial landscapes that may be evident to anyone: even if local exceptions exist, wide fluvial valleys in plains are distinctive of narrow upstream mountainous ones. Yet, the processes and rates governing along-stream valley widening over timescales characteristic of landscape development (&gt;1-10 ka) are largely unknown. No suitable law exists in landscape evolution models, thus models imperfectly reproduce the landscape evolution at geological timescales, their rates of erosion and probably their response to tectonics and climate. Here, we study two 1 km-deep canyons in northern Chile with diachronous incision initiation, thus representing two time-stage evolutions of a similar geomorphic system characterized by valley widening following the upward migration of a major knickzone. We use 10Be cosmogenic isotope concentrations measured in colluvial deposits at the foot of hillslopes to quantify along-stream valley flank erosion rates. We observe that valley flank erosion rate increases quasi-linearly with valley-bed slope and decreases non-linearly with valley width. This relation suggests that lateral erosion increases with sediment flux due to higher channel mobility. In turn, valley width exerts a negative feedback on lateral valley flank erosion since channels in wide valleys have a lower probability of eroding the valley sides. This implies a major control of river divagation on valley flank erosion rate and valley widening. Our study provides the first data for understanding the long-term processes and rates governing valley widening in landscapes.&lt;/p&gt;

scholarly journals Distinct phases of eustatism and tectonics control the late Quaternary landscape evolution at the southern coastline of Crete

2016 ◽  
Author(s):  
Vasiliki Mouslopoulou ◽  
John Begg ◽  
Alexander Fülling ◽  
Daniel Moraetis ◽  
Panagiotis Partsinevelos ◽  
...  
Keyword(s):  
Landscape Evolution ◽  
Late Quaternary ◽  
Eastern Mediterranean ◽  
Vertical Movement ◽  
Tectonic Uplift ◽  
Alluvial Fan ◽  
Contributing Factors ◽  
River Incision ◽  
Coastal Landscapes ◽  
Uplift Rates

Abstract. The extent to which climate, eustacy and tectonics interact to shape the late Quaternary landscape is poorly known. Alluvial fans often provide useful indexes that allow decoding the information recorded on complex coastal landscapes, such as those of Eastern Mediterranean. In this paper we analyse and date (using optically stimulated luminescence – OSL) a double alluvial-fan system in Crete, an island straddling the forearc of the Hellenic subduction margin, in order to constrain the timing of, and quantify the contributing factors to, its landscape evolution. The studied alluvial system is unique because each of its two juxtaposed fans records individual phases of alluvial and marine incision, providing, thus, unprecedented resolution in the formation and evolution of its landscape. Specifically, our analysis shows that the fan sequence at Domata developed during the last glaciation (Marine Isotope Stage 3; 57–29 kyr) due to five distinct stages of marine transgressions and regressions and associated river incision, as a response to climatic changes and tectonic uplift at rates of ~ 2.2 mm/yr. Comparison of our results with published tectonic uplift rates from Crete shows, however, that vertical movement on Crete was minimal during 20–50 kyr BP and mot uplift was accrued during the last 20 kyr. This implies that eustacy and tectonism impacted on the landscape at Domata over mainly distinct time-intervals (e.g. sequentially and not synchronously), forming and preserving the coastal landforms, respectively.

scholarly journals Accurate simulation of transient landscape evolution by eliminating numerical diffusion: the TTLEM 1.0 model

2016 ◽  
Author(s):  
Benjamin Campforts ◽  
Wolfgang Schwanghart ◽  
Gerard Govers
Keyword(s):  
Landscape Evolution ◽  
Advection Equation ◽  
Spatial And Temporal Variability ◽  
Numerical Diffusion ◽  
Erosion Rates ◽  
River Incision ◽  
Wide Range ◽  
Integrated Response ◽  
Volume Method ◽  
Flux Limiting

Abstract. Landscape evolution models (LEM) allow studying the earth surface response to a changing climatic and tectonic forcing. While much effort has been devoted to the development of LEMs that simulate a wide range of processes, the numerical accuracy of these models has received much less attention. Most LEMs use first order accurate numerical methods that suffer from substantial numerical diffusion. Numerical diffusion particularly affects the solution of the advection equation and thus the simulation of retreating landforms such as cliffs and river knickpoints with potential unquantified consequences for the integrated response of the simulated landscape. Here we present TTLEM, a spatially explicit, raster based LEM for the study of fluvially eroding landscapes in TopoToolbox 2. TTLEM prevents numerical diffusion by implementing a higher order flux limiting total volume method that is total variation diminishing (TVD-TVM) and solves the partial differential equations of river incision and tectonic displacement. We show that the choice of the TVD-TVM to simulate river incision significantly influences the evolution of simulated landscapes and the spatial and temporal variability of catchment wide erosion rates. Furthermore, a 2D TVD-TVM accurately simulates the evolution of landscapes affected by lateral tectonic displacement, a process whose simulation is hitherto largely limited to LEMs with flexible spatial discretization. By providing accurate numerical schemes on rectangular grids, TTLEM is a widely accessible LEM that is compatible with GIS analysis functions from the TopoToolbox interface.

scholarly journals The SPACE 1.0 model: a Landlab component for 2-D calculation of sediment transport, bedrock erosion, and landscape evolution

2017 ◽  
Vol 10 (12) ◽  
pp. 4577-4604 ◽  
Author(s):  
Charles M. Shobe ◽  
Gregory E. Tucker ◽  
Katherine R. Barnhart
Keyword(s):  
Sediment Transport ◽  
Analytical Solutions ◽  
Landscape Evolution ◽  
Sediment Flux ◽  
Process Models ◽  
Surface Processes ◽  
Flux Divergence ◽  
Space Model ◽  
Lithospheric Flexure ◽  
Bedrock Erosion

Abstract. Models of landscape evolution by river erosion are often either transport-limited (sediment is always available but may or may not be transportable) or detachment-limited (sediment must be detached from the bed but is then always transportable). While several models incorporate elements of, or transition between, transport-limited and detachment-limited behavior, most require that either sediment or bedrock, but not both, are eroded at any given time. Modeling landscape evolution over large spatial and temporal scales requires a model that can (1) transition freely between transport-limited and detachment-limited behavior, (2) simultaneously treat sediment transport and bedrock erosion, and (3) run in 2-D over large grids and be coupled with other surface process models. We present SPACE (stream power with alluvium conservation and entrainment) 1.0, a new model for simultaneous evolution of an alluvium layer and a bedrock bed based on conservation of sediment mass both on the bed and in the water column. The model treats sediment transport and bedrock erosion simultaneously, embracing the reality that many rivers (even those commonly defined as bedrock rivers) flow over a partially alluviated bed. SPACE improves on previous models of bedrock–alluvial rivers by explicitly calculating sediment erosion and deposition rather than relying on a flux-divergence (Exner) approach. The SPACE model is a component of the Landlab modeling toolkit, a Python-language library used to create models of Earth surface processes. Landlab allows efficient coupling between the SPACE model and components simulating basin hydrology, hillslope evolution, weathering, lithospheric flexure, and other surface processes. Here, we first derive the governing equations of the SPACE model from existing sediment transport and bedrock erosion formulations and explore the behavior of local analytical solutions for sediment flux and alluvium thickness. We derive steady-state analytical solutions for channel slope, alluvium thickness, and sediment flux, and show that SPACE matches predicted behavior in detachment-limited, transport-limited, and mixed conditions. We provide an example of landscape evolution modeling in which SPACE is coupled with hillslope diffusion, and demonstrate that SPACE provides an effective framework for simultaneously modeling 2-D sediment transport and bedrock erosion.

scholarly journals Accurate simulation of transient landscape evolution by eliminating numerical diffusion: the TTLEM 1.0 model

2017 ◽  
Vol 5 (1) ◽  
pp. 47-66 ◽  
Author(s):  
Benjamin Campforts ◽  
Wolfgang Schwanghart ◽  
Gerard Govers
Keyword(s):  
Landscape Evolution ◽  
Advection Equation ◽  
Spatial And Temporal Variability ◽  
Numerical Diffusion ◽  
Erosion Rates ◽  
River Incision ◽  
Wide Range ◽  
Integrated Response ◽  
Volume Method ◽  
Flux Limiting

Abstract. Landscape evolution models (LEMs) allow the study of earth surface responses to changing climatic and tectonic forcings. While much effort has been devoted to the development of LEMs that simulate a wide range of processes, the numerical accuracy of these models has received less attention. Most LEMs use first-order accurate numerical methods that suffer from substantial numerical diffusion. Numerical diffusion particularly affects the solution of the advection equation and thus the simulation of retreating landforms such as cliffs and river knickpoints. This has potential consequences for the integrated response of the simulated landscape. Here we test a higher-order flux-limiting finite volume method that is total variation diminishing (TVD-FVM) to solve the partial differential equations of river incision and tectonic displacement. We show that using the TVD-FVM to simulate river incision significantly influences the evolution of simulated landscapes and the spatial and temporal variability of catchment-wide erosion rates. Furthermore, a two-dimensional TVD-FVM accurately simulates the evolution of landscapes affected by lateral tectonic displacement, a process whose simulation was hitherto largely limited to LEMs with flexible spatial discretization. We implement the scheme in TTLEM (TopoToolbox Landscape Evolution Model), a spatially explicit, raster-based LEM for the study of fluvially eroding landscapes in TopoToolbox 2.

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