Aeolian Sediment Transport and Natural Dune Development, Skodbjerge, Denmark
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Geomorphology, Stratigraphy, and Paleohydrology of the Aeolis Dorsa Region, Mars, with Insights from Modern and Ancient Terrestrial Analogs
University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 12-2016 Geomorphology, Stratigraphy, and Paleohydrology of the Aeolis Dorsa region, Mars, with Insights from Modern and Ancient Terrestrial Analogs Robert Eric Jacobsen II University of Tennessee, Knoxville, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Part of the Geology Commons Recommended Citation Jacobsen, Robert Eric II, "Geomorphology, Stratigraphy, and Paleohydrology of the Aeolis Dorsa region, Mars, with Insights from Modern and Ancient Terrestrial Analogs. " PhD diss., University of Tennessee, 2016. https://trace.tennessee.edu/utk_graddiss/4098 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Robert Eric Jacobsen II entitled "Geomorphology, Stratigraphy, and Paleohydrology of the Aeolis Dorsa region, Mars, with Insights from Modern and Ancient Terrestrial Analogs." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Geology. Devon M. Burr, -
Sediment Transport and the Genesis Flood — Case Studies Including the Hawkesbury Sandstone, Sydney
Sediment Transport and the Genesis Flood — Case Studies including the Hawkesbury Sandstone, Sydney DAVID ALLEN ABSTRACT The rates at which parts of the geological record have formed can be roughly determined using physical sedimentology independently from other dating methods if current understanding of the processes involved in sedimentology are accurate. Bedform and particle size observations are used here, along with sediment transport equations, to determine rates of transport and deposition in various geological sections. Calculations based on properties of some very extensive rock units suggest that those units have been deposited at rates faster than any observed today and orders of magnitude faster than suggested by radioisotopic dating. Settling velocity equations wrongly suggest that rapid fine particle deposition is impossible, since many experiments and observations (for example, Mt St Helens, mud- flows) demonstrate that the conditions which cause faster rates of deposition than those calculated here are not fully understood. For coarser particles the only parameters that, when varied through reasonable ranges, very significantly affect transport rates are flow velocity and grain diameter. Popular geological models that attempt to harmonize the Genesis Flood with stratigraphy require that, during the Flood, most deposition believed to have occurred during the Palaeozoic and Mesozoic eras would have actually been the result of about one year of geological activity. Flow regimes required for the Flood to have deposited various geological cross- sections have been proposed, but the most reliable estimate of water velocity required by the Flood was attained for a section through the Tasman Fold Belt of Eastern Australia and equalled very approximately 30 ms-1 (100 km h-1). -
Sediment Transport in the San Francisco Bay Coastal System: an Overview
Marine Geology 345 (2013) 3–17 Contents lists available at ScienceDirect Marine Geology journal homepage: www.elsevier.com/locate/margeo Sediment transport in the San Francisco Bay Coastal System: An overview Patrick L. Barnard a,⁎, David H. Schoellhamer b,c, Bruce E. Jaffe a, Lester J. McKee d a U.S. Geological Survey, Pacific Coastal and Marine Science Center, Santa Cruz, CA, USA b U.S. Geological Survey, California Water Science Center, Sacramento, CA, USA c University of California, Davis, USA d San Francisco Estuary Institute, Richmond, CA, USA article info abstract Article history: The papers in this special issue feature state-of-the-art approaches to understanding the physical processes Received 29 March 2012 related to sediment transport and geomorphology of complex coastal–estuarine systems. Here we focus on Received in revised form 9 April 2013 the San Francisco Bay Coastal System, extending from the lower San Joaquin–Sacramento Delta, through the Accepted 13 April 2013 Bay, and along the adjacent outer Pacific Coast. San Francisco Bay is an urbanized estuary that is impacted by Available online 20 April 2013 numerous anthropogenic activities common to many large estuaries, including a mining legacy, channel dredging, aggregate mining, reservoirs, freshwater diversion, watershed modifications, urban run-off, ship traffic, exotic Keywords: sediment transport species introductions, land reclamation, and wetland restoration. The Golden Gate strait is the sole inlet 9 3 estuaries connecting the Bay to the Pacific Ocean, and serves as the conduit for a tidal flow of ~8 × 10 m /day, in addition circulation to the transport of mud, sand, biogenic material, nutrients, and pollutants. -
Erosion Is the Process Where Soft Shorelines (Sand, Gravel Or Cobble) Disappear and Land Is Lost
COASTAL EROSION Action Guide What is Coastal Erosion? Erosion is the process where soft shorelines (sand, gravel or cobble) disappear and land is lost. Erosion generally comes in two forms: 1. A Natural part of the coastal environment where a soft shore moves and changes in response to cyclic climate conditions and 2. Erosion can be induced by human interference of natural sand movement and budget patterns. Erosion can be slow and ongoing over many years or fast and dramatic following large storm events. Many erosion problems in the Pacific today, occur because of poor planning, inappropriate shoreline development, overcrowding, beach mining for building material and due to reef degradation. Erosion is a natural process It is important to understand that erosion is a natural process and in many cases is accompanied by its equal and opposite process “accretion”. Put simply, sandy shorelines are dynamic and should be expected to shift and change over time, sometimes by 100’s of meters. This process becomes an “erosion problem” if development is not carefully planned to avoid unstable shorelines. Why is it that erosion seems more of a problem these days? In past times, people lived in harmony with their moving coasts. Their houses could be easily moved to and shoreline homes were built in way which did not disturb shoreline processes (eg. On stilts or pylons). People knew and avoided dangerous or unstable locations. Today, building styles have changed and homes cannot be easily moved or replaced and lack of space often results in people building in locations which are known to be inappropriate. -
PDF Brunel Et Al., 2014
Geomorphology 204 (2014) 625–637 Contents lists available at ScienceDirect Geomorphology journal homepage: www.elsevier.com/locate/geomorph 20th century sediment budget trends on the Western Gulf of Lions shoreface (France): An application of an integrated method for the study of sediment coastal reservoirs C. Brunel a,⁎,R.Certaina, F. Sabatier b,N.Robina, J.P. Barusseau a,N.Alemana, O. Raynal a a Université de Perpignan, Laboratoire d'Etudes des Géo-Environnements Marins, 52 av. P Alduy, 66860 Perpignan, France b Aix Marseille Université, CEREGE, UMR 7330 CNRS, Europôle Méditerranéen de l'Arbois, 13545 Aix en Provence Cedex 4, France article info abstract Article history: This paper presents a shoreface sediment budget established for the 20th century (1895–1984–2009) along the Received 17 April 2013 microtidal wave-dominated coast of the western Gulf of Lions (Languedoc-Roussillon, Mediterranean Sea, SE Received in revised form 6 September 2013 France). The implementation of a diachronic bathymetric approach, coupled with the definition of sand reser- Accepted 12 September 2013 voirs (upper sand unit — USU) by very high-resolution seismic surveys and the results of LiDAR investigations, Available online 2 October 2013 offers a new means of defining precisely the magnitude and change trends of the sediment budget. The aim of this study is to link the Large Scale Coastal Behaviour (LSCB) of the littoral prism (expressed in terms of shoreface Keywords: Shoreface sediment budget sediment budget, shoreface sediment volume and spatial distribution pattern of cells) to climatic change, river Large Scale Coastal Behaviour sediment input to the coast, longshore sediment transport distribution, impact of hard coastal defence structures Seismic surveys and artificial beach nourishment. -
The Role of Geology in Sediment Supply and Bedload Transport Patterns in Coarse Grained Streams
The Role of Geology in Sediment Supply and Bedload Transport Patterns in Coarse Grained Streams Sandra E. Ryan USDA Forest Service, Rocky Mountain Research Station, Fort Collins, Colorado This paper compares gross differences in rates of bedload sediment moved at bankfull discharges in 19 channels on national forests in the Middle and Southern Rocky Mountains. Each stream has its own “bedload signal,” in that the rate and size of materials transported at bankfull discharge largely reflect the nature of flow and sediment particular to that system. However, when rates of bedload transport were normalized by dividing by the watershed area, the results were similar for many sites. Typically, streams exhibited normalized rates of bedload transport between 0.001 and 0.003 kg s-1 km-2 at bankfull discharges. Given the inherent difficulty of obtaining a reliable estimate of mean rates of bedload transport, the relatively narrow range of values observed for these systems is notable. While many of these sites are underlain by different geologic terrane, they appear to have comparable patterns of mass wasting contributing to sediment supply under current climatic conditions. There were, however, some sites where there was considerable departure from the normalized range of values. These sites typically had different patterns and qualitative rates of mass wasting, either higher or lower, than observed for other watersheds. The gross differences in sediment supply to the stream network have been used to account for departures in the normalized rates of bedload transport observed for these sites. The next phase of this work is to better quantify the contributions from hillslopes to help explain variability in the normalized rate of bedload transport. -
Aeolian Processes and Landforms
Aeolian Processes and Landforms Ms. Deithra L. Archie, New Mexico State University Abstract I will present an overview of Aeolian processes and landforms on Mars. The overview will consist of two components. Component one is an overview of Aeolian processes and landforms on Earth and Mars, where the two planetary bodies are shown in Figures 1a and 1b respectively The second part of this paper will consist of image comparisons using satellite and MOC (Mars Orbiter Camera) images. Figure 1a Figure 1b Introduction Understanding the aeolian activity on the planet Mars and other planets begins with the study and knowledge of similar processes on Earth. Therefore, I will discuss the following: wind, particle entrainment and landforms found in the aeolian environment. This discussion will lead into my later discussion of the Martian sand seas and sand dunes. See Table 1 for a glossary of the terms used throughout this paper. In aeolian processes, wind transports and deposits particles of sediment. Aeolian features form in areas where wind is the primary source of erosion. The particles deposited are of sand, silt and clay size (see Table 2). The particles are entrained in by one of four processes. Creep is when a particle rolls or slides across the surface. Lift is when a particle rises off the surface due to the Bernoulli effect, the same mechanism which causes aircraft to rise. If the airflow is turbulent, larger particles are trajected by a process known as saltation. Finally, impact transport occurs which one particle strikes another causing the second particle to move. Erosional Landforms Wind eroded landforms are rarely preserved on the surface of the Earth except in arid regions. -
Modeling and Practice of Erosion and Sediment Transport Under Change
water Editorial Modeling and Practice of Erosion and Sediment Transport under Change Hafzullah Aksoy 1,* , Gil Mahe 2 and Mohamed Meddi 3 1 Department of Civil Engineering, Istanbul Technical University, 34469 Istanbul, Turkey 2 IRD, UMR HSM IRD/ CNRS/ University Montpellier, Place E. Bataillon, 34095 Montpellier, France 3 Ecole Nationale Supérieure d’Hydraulique, LGEE, Blida 9000, Algeria * Correspondence: [email protected] Received: 27 May 2019; Accepted: 9 August 2019; Published: 12 August 2019 Abstract: Climate and anthropogenic changes impact on the erosion and sediment transport processes in rivers. Rainfall variability and, in many places, the increase of rainfall intensity have a direct impact on rainfall erosivity. Increasing changes in demography have led to the acceleration of land cover changes from natural areas to cultivated areas, and then from degraded areas to desertification. Such areas, under the effect of anthropogenic activities, are more sensitive to erosion, and are therefore prone to erosion. On the other hand, with an increase in the number of dams in watersheds, a great portion of sediment fluxes is trapped in the reservoirs, which do not reach the sea in the same amount nor at the same quality, and thus have consequences for coastal geomorphodynamics. The Special Issue “Modeling and Practice of Erosion and Sediment Transport under Change” is focused on a number of keywords: erosion and sediment transport, model and practice, and change. The keywords are briefly discussed with respect to the relevant literature. The papers in this Special Issue address observations and models based on laboratory and field data, allowing researchers to make use of such resources in practice under changing conditions. -
Predicting Shoreline Evolution on a Centennial Scale Using the Example of the Vistula (Baltic) Spit I
ISSN 00014370, Oceanology, 2012, Vol. 52, No. 5, pp. 700–709. © Pleiades Publishing, Inc., 2012. Original Russian Text © I.O. Leont’yev, 2012, published in Okeanologiya, 2012, Vol. 52, No. 5, pp. 757–767. MARINE GEOLOGY Predicting Shoreline Evolution on a Centennial Scale Using the Example of the Vistula (Baltic) Spit I. O. Leont’yev Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, Russia Email: [email protected] Received March 31, 2011; in final form, November 22, 2011 Abstract—The proposed algorithm comprises three main steps. The first step is the evaluation of the sedi ment transport and budget. It was shown that the root segment of the Vistula Spit is dominated by eastward longshore sediment transport (up to 50 thousand m3/year). Over the rest of the spit, the shoreline’s orienta tion causes westward sediment transport (more than 100 thousand m3/year). The gradients of the longshore and cross shore sediment transport become the major contributors to the overall sediment balance. The only exception is the northeastern tip of the spit due to the appreciable imbalance of the sediment budget (13 m3 m–1 yr–1). The second step in the prediction modeling is the estimation of the potential sealevel changes during the 21st century. The third step involves modeling of the shoreline’s behavior using the SPELT model [6, 7, 8]. In the most likely scenario, the rate of the recession is predicted to be about 0.3 m/year in 2010–2050 and will increase to 0.4 m/year in 2050–2100. The sand deficit, other than the sealevel rise, will be a key factor in the control of the shoreline’s evolution at the northeastern tip of the spit, and the amount of recession will range from 160 to 200 m in 2010–2100. -
Bedload Equation for Ripples and Dunes
Bedload Equation for Ripples and Dunes GEOLOGICAL SURVEY PROFESSIONAL PAPER 462-H Bedload Equation for Ripples and Dunes By D. B. SIMONS, E. V. RICHARDSON, and C. F. NORDIN, JR. SEDIMENT TRANSPORT IN ALLUVIAL CHANNELS GEOLOGICAL SURVEY PROFESSIONAL PAPER 462-H An examination of conditions under which bed- load transport rates may be determined from the dimensions and speed of shifting bed forms UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1965 UNITED STATES DEPARTMENT OF THE INTERIOR STEWART L. UDALL, Secretary GEOLOGICAL SURVEY Thomas B. Nolan, Director For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price 20 cents (paper cover) CONTENTS Page Page Symbols. _______________________ ___________________ IV Bedload Transport __ ______________ . _____ ___ __ HI Abstract __ __________ ___ ___ .__._--_____._..___ HI Conclusions_______________ ________ _________ _ ____ 7 Introduction ____________________ _______ _ 1 References cited. ___________________ _ __ ___________ 9 ILLUSTRATIONS Page FIGURES 4-7. Relation of Page FIGURE 1. Definition sketch of dunes. H2 4. V.to(V-V H5 . Vs 2. Comparison of computed bedload with 5. 6 observed bed-material load__________ 3 V-VQ g 6. h to 3. Comparison of computed and observed (V V\ bedload.___________________________ 7. qriOToV[~y~ )______ _______ 8 TABLE Page TABLE 1. Variables considered. H2 m LIST OF SYMBOLS C Chezy coefficient Ci A constant D Mean depth g Accleration due to gravity h Average ripple or dune amplitude KI, K2) Ka, KI, K5 Constants q_b Bedload, by volume or weight qr Bed material load S Slope of the energy gradient t Time V Mean velocity VQ Noneroding mean velocity Vs Average velocity of ripples or dunes in the direction of flow x Distance parallel to the direction of flow y Elevation of the bed above an arbitrary horizontal datum 7 Unit weight of the fluid 5 A transformation, 5=x Vst TO The shear stress at the bed X Porosity of the sand bed d Partial derivative SEDIMENT TRANSPORT IN ALLUVIAL CHANNELS BEDLOAD EQUATION FOR RIPPLES AND DUNES By D. -
Sea Level Rise and Coastal Morphological Changes on Tropical Islands New Caledonia and French Polynesia (South Pacific) the Project
Manuel Garcin, Marissa Yates, Goneri Le Cozannet, Patrice Walker, Vincent Donato Sea level rise and coastal morphological changes on tropical islands New Caledonia and French Polynesia (South Pacific) The Project • Work completed within the CECILE project (Coastal Environmental Changes: Impact of sea LEvel rise )=> See Poster Le Cozannet et al. same session • Project objectives: to contribute to assessing the physical impact of sea level rise on shorelines during the recent past (last 50 years) and near future (next 100 years). • Focus on tropical islands : New Caledonia, French Polynesia, La Réunion (Indian Ocean), French Caribbean • What is the importance of recent sea level rise with respect to other causes of change ? • What will be the consequences of sea level rise for coastal change in the future ? GARCIN M., YATES M., LE COZANNET G., WALKER P., DONATO V. (EGU 2011) ‐ Sea level rise and coastal morphological changes on tropical islands Generic driving factors influencing coastline mobility, dynamics and morphology Coastline mobility is an indicator integrating numerous parameters • 5 families of driving factors affecting coastline mobility Erosion, accretion, transport... – Climate change External geodynamics – External geodynamic processes Pluviometry processes linked to climate change Biological Sea Level – Internal geodynamic Change, processes winds, storms, processes pluviometry... – Biological processes Coastline Anthropogenic Climate change actions and – Anthropogenic actions and mobility impacts impacts Tectonic, vertical Sea defences, • To note : interactions & movements, gravels isostasy... extraction, mining, retroactions daming.... Internal geodynamics processes GARCIN M., YATES M., LE COZANNET G., WALKER P., DONATO V. (EGU 2011) ‐ Sea level rise and coastal morphological changes on tropical islands Driving factors Or The data problem GARCIN M., YATES M., LE COZANNET G., WALKER P., DONATO V. -
Erosion and Sediment Transport
Erosion and sediment transport Lecture content Skript: Ch. VIII – rationale for understanding and modelling erosion and sediment transport processes – surface erosion – mechanisms – interaction with climate, land cover and topography – annual scale surface erosion model – sediment transport in streams – mechanisms – measurements – sediment characterisation – condition for incipient motion – sediment transport equation Hydrology – Erosion and Sediment Transport – Autumn Semester 2017 1 Erosion and sediment transport is driven • by hydrological processes in the watershed • by stream hydraulics in rivers plays an important role with regard to • evolution of landscape • loss of agricultural soils • stability of river beds • water resources infrastructures (dams, …) • natural hazards • coastal processes ⤵ Brienzersee,)Hochwasser)2005) Hochwasser/Murgang) Copyright © Philip Owens 2002 Hydrology – Erosion and Sediment Transport – Autumn Semester 2017 2 Examples of effects of erosion and sediment transport on water infrastructures • filling in of reservoirs – reduces the active volume of the reservoir intake – can put at risk the correct operation of the reservoir organs (e.g. intakes) multipurpose • river bed aggradation reservoir deposited sediments = dead volume – due to sediment deposition after a flood event – due to imbalance between sediment supply from upstream and flow energy • scour in river beds and embankment erosion – undermines the stability of river cross sections • pumps and turbines ⤵ • water supply derivations • ecosystems •