Initiation and Evolution of Knickpoints and Their Role in Cut-And-Fill
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Monitoring the Effects of Knickpoint Erosion on Bridge Pier and Abutment Structural Damage Due to Scour Thanos Papanicolaou University of Iowa, [email protected]
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Final Reports & Technical Briefs from Mid-America Mid-America Transportation Center Transportation Center 2012 Monitoring the Effects of Knickpoint Erosion on Bridge Pier and Abutment Structural Damage Due to Scour Thanos Papanicolaou University of Iowa, [email protected] David M. Admiraal University of Nebraska-Lincoln, [email protected] Christopher Wilson University of Nebraska-Lincoln Clark W. Kephart University of Nebraska-Lincoln, [email protected] Follow this and additional works at: http://digitalcommons.unl.edu/matcreports Part of the Civil Engineering Commons Papanicolaou, Thanos; Admiraal, David M.; Wilson, Christopher; and Kephart, Clark W., "Monitoring the Effects of Knickpoint Erosion on Bridge Pier and Abutment Structural Damage Due to Scour" (2012). Final Reports & Technical Briefs from Mid-America Transportation Center. 3. http://digitalcommons.unl.edu/matcreports/3 This Article is brought to you for free and open access by the Mid-America Transportation Center at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Final Reports & Technical Briefs from Mid-America Transportation Center by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Report # MATC-UI-UNL: 471/424 Final Report 25-1121-0001-471, 25-1121-0001-424 Monitoring the Effects of Knickpoint Erosion ® on Bridge Pier and Abutment Structural Damage Due to Scour A.N. Thanos Papanicolaou, Ph.D. Professor Department of Civil and Environmental Engineering IIHR—Hydroscience & Engineering University of Iowa David M. Admiraal, Ph.D. Associate Professor Christopher Wilson, Ph.D. Assistant Research Scientist Clark Kephart Graduate Research Assistant 2012 A Cooperative Research Project sponsored by the U.S. -
Rapidly-Migrating and Internally-Generated Knickpoints Can Control 2 Submarine Channel Evolution 3 4 Maarten S
1 Rapidly-migrating and internally-generated knickpoints can control 2 submarine channel evolution 3 4 Maarten S. Heijnen1,2,*, Michael A. Clare1, Matthieu J.B. Cartigny3, Peter J. Talling3, Sophie 5 Hage2, D. Gwyn Lintern4, Cooper Stacey4, Daniel R. Parsons5, Stephen M. Simmons5, Ye 6 Chen5, Esther J. Sumner2, Justin K. Dix2, John E. Hughes Clarke6, 7 8 1Marine Geosciences, National Oceanography Centre, European Way, Southampton, U.K. 9 2Ocean and Earth Sciences, National Oceanography Centre, University of Southampton, European Way, 10 Southampton, U.K. 11 3Departments of Geography and Earth Sciences, University of Durham, South Rd, Durham, U. K. 12 4Natural Resources Canada, Geological Survey of Canada, Box 6000, 9860 West Saanich Road, Sidney BC, 13 Canada. 14 5School of Environmental Sciences, University of Hull, U.K. 15 6Earth Sciences, Center for Coastal & Ocean Mapping, University of New Hampshire, 24 Colovos Road, Durham, 16 U.S.A. 17 *corresponding author: [email protected] 18 19 Abstract 20 Submarine channels are the primary conduits for terrestrial sediment, organic carbon, and 21 pollutant transport to the deep sea. Submarine channels are far more difficult to monitor 22 than rivers, and thus less well understood. Here we present the longest (9 year) time-lapse 23 mapping yet for a submarine channel. Past studies suggested that gradual meander-bend 24 migration, levee-deposition, or migration of (supercritical-flow) bedforms controls the 25 evolution of submarine channels. We show for the first time how exceptionally rapid (100- 26 450 m/year) upstream migration of 5-to-30 m high knickpoints can control how submarine 27 channels evolve. -
A Systematic Approach and Software for the Analysis of Point Patterns On
This is a preprint. Manuscript submitted to Earth Surface Processes and Landforms. 1 A systematic approach and software for 2 the analysis of point patterns on river 3 networks 4 5 Wolfgang Schwanghart1*, Christian Molkenthin2, Dirk Scherler3,4 6 7 1 Institute of Environmental Science and Geography, University of Potsdam, 14476 Potsdam-Golm, 8 Germany 9 2 Institute of Mathematics, University of Potsdam, 14476 Potsdam-Golm, Germany 10 3 German Research Centre for Geosciences (GFZ), Earth Surface Geochemistry, 14473 Potsdam, 11 Germany 12 4 Institute of Geological Sciences, Freie Universität Berlin, 12249 Berlin, Germany 13 * Corresponding author: [email protected] 14 15 Keywords: Point pattern analysis, point processes, fluvial geomorphology, knickpoints, beaver dams 16 17 Abstract 18 Many geomorphic phenomena such as bank failures, landslide dams, riffle-pool sequences and 19 knickpoints can be modelled as spatial point processes. However, as the locations of these phenomena 20 are constrained to lie on or alongside rivers, their analysis must account for the geometry and topology 21 of river networks. Here, we introduce a new numeric class in TopoToolbox called Point Pattern on 22 Stream networks (PPS), which supports exploratory analysis, statistical modelling, simulation and 23 visualization of point processes. We present two case studies that aim at inferring processes and 24 factors that control the spatial density of geomorphic phenomena along river networks: the analysis of 25 knickpoints in river profiles, and modelling spatial locations of beaver dams based on topographic 26 metrics. The case studies rely on exploratory analysis and statistical inference using inhomogeneous 27 Poisson point processes. -
Measuring Knickpoint Migration in Ravine Z, Seven
Measuring Knickpoint Migration in Ravine Z, Seven Mile Creek Park, Nicollet County, MN By Michael Dickens A thesis submitted in partial fulfillment of the requirements of the degree of Bachelor of Arts (Geology) at Gustavus Adolphus College 2015 Measuring Knickpoint Migration in Ravine Z, Seven Mile Creek Park, Nicollet County, MN By Michael Dickens Under the supervision of Laura Triplett Abstract The Minnesota River is facing increasing sediment loads, which are a result of sediment erosion in the rivers watershed. Likely sources for that sediment include upland topsoil, incising and head-cutting ravines, Bluffs and streambanks. The focus of this study is ravines, which are poorly understood in terms of erosional processes. One main way that ravines erode is through knickpoint migration, which happens as water flows over a tougher material, and falls onto a softer material, creating a back-cutting and over-steepening effect at the toe of the knickpoint. Material from the Bottom of the ravine is thus moBilized, and can be transported down the ravine into the Minnesota River. To help decipher the role of knickpoint migration in sediment loading on the Minnesota River, we examined a single ravine and its knickpoints over a span of several years. Seven Mile Creek, a tributary to the Minnesota River in Nicollet County, is an ideal location to study the factors that contribute to knickpoint migration. Ravine Z, a prominent ravine in Seven Mile Creek Park, Nicollet County, MN, is a very active eroding channel that is largely fed By farm drainage tiles. A digital elevation model and surveying tools were used to make a series of slope profiles spanning the period 2007-2014. -
Knickpoint Recession Rate and Catchment Area: the Case of Uplifted Rivers in Eastern Scotland
Bishop, P. and Hoey, T. B. and Jansen, J. D. and Artza, I. L. (2005) Knickpoint recession rate and catchment area: the case of uplifted rivers in Eastern Scotland. Earth Surface Processes and Landforms 30(6):pp. 767-778. http://eprints.gla.ac.uk/3395/ 7 Knickpoint recession rate and catchment area: the case of uplifted rivers in Eastern Scotland Paul Bishop,* Trevor B. Hoey, John D. Jansen and Irantzu Lexartza Artza Department of Geography and Geomatics, Centre for Geosciences, University of Glasgow, Glasgow G12 8QQ, UK *Correspondence to: P. Bishop, Abstract Department of Geography and Geomatics, Centre for Knickpoint behaviour is a key to understanding both the landscape responses to a base-level Geosciences, University of fall and the corresponding sediment fluxes from rejuvenated catchments, and must be ac- Glasgow, Glasgow, G12 commodated in numerical models of large-scale landscape evolution. Knickpoint recession 8QQ, UK. E-mail: in streams draining to glacio-isostatically uplifted shorelines in eastern Scotland is used [email protected] to assess whether knickpoint recession is a function of discharge (here represented by its surrogate, catchment area). Knickpoints are identified using DS plots (log slope versus log downstream distance). A statistically significant power relationship is found between dis- tance of headward recession and catchment area. Such knickpoint recession data may be used to determine the values of m and n in the stream power law, E = KAmSn. The data have too many uncertainties, however, to judge definitively whether they are consistent with m = n = 1 (bedrock erosion is proportional to stream power and KPs should be maintained and propagate headwards) or m = 0·3, n = 0·7 (bedrock incision is proportional to shear stress and KPs do not propagate but degrade in place by rotation or replacement). -
Explain How Rivers Adjust to a Change in Base Level, with Reference to Example(S) That You Have Studied
Explain how rivers adjust to a change in base level, with reference to example(s) that you have studied. (30 marks) The base level of a river is the lowest level at which river erosion can take place, which is sea level. Changes in sea level over time can be a result of climate or tectonic activity. If the land level rises or the sea level falls, there is a drop in the base level. This will result in the land rising when compared to the sea level. The new river profile will now flow faster to the sea as vertical erosion cuts into the river bed. This process is called rejuvenation. New landforms such as knickpoints and paired terraces are formed as a result. Waterfalls are usually only found in the youthful stage of a river as the river runs down a steep slope, vertically eroding. Knickpoints are small waterfalls found in the lower course of a river. They occur at the point where the river once entered the sea. Due to isostatic uplift the sea level was lowered and the river had to now travel a longer distance to reach the sea. The river was “rejuvenated” as it was given renewed ability to vertically. The rejuvenated river cuts a new profile for itself and the place where the new profile meets the old profile is known as the knickpoint. An example of a knickpoint in Ireland can be seen on the River Erne in Co. Donegal at Kathleen’s Falls. When a former flood plain of the old age stage is uplifted, river rejuvenation affects this region to form the second feature I will discuss which are paired terraces. -
The Problem of Channel Erosion Into Bedrock
CATENA SUPPLEMENT 23 p. 101-124 Cremlingen 1992 The Problem of Channel Erosion into Bedrock MA. Seidl & W.E. Dietrich Summary Although river incision into the bedrock of uplifted regions creates the dissected topography of landscapes, little is known about the process of channel erosion into bedrock. Here we present a testable framework for the study of fluvial incision into bedrock that combines theory with field observation. We quantify a simple erosion law by measuring drainage areas and slopes on both principal channels and tributaries. The data suggest that both a bedrock tributary and main stem will lower at the same rate at their confluence if the ratio of main stem to tributary drainage area equals the ratio of tributary to main stem channel slope at the junction. Erosion across several tributary junctions is therefore linearly related to stream power. Tributary slopes greater than about 0.2 deviate from this linear prediction, apparentiy because debris flows scour these steep tributaries. Further field study suggests that the common elevation of tributary and main stem may result from the upslope propagation of locally steep reaches generated at tributary mouths. This propagation continues only to the point on the channel where the channel slope is too steep to preserve the oversteepened reach, or knickpoint, and debris flow scour dominates channel erosion. Our results suggest three general mechanisms by which bedrock channels erode: (1) vertical wearing of the channel bed due to stream flow, by such processes as abrasion by transported particles and dissolution; (2) scour by periodic debris flows; and (3) knickpoint propagation. -
Statistical Modelling of Co-Seismic Knickpoint Formation and River Response to Fault Slip Philippe Steer, Thomas Croissant, Edwin Baynes, Dimitri Lague
Statistical modelling of co-seismic knickpoint formation and river response to fault slip Philippe Steer, Thomas Croissant, Edwin Baynes, Dimitri Lague To cite this version: Philippe Steer, Thomas Croissant, Edwin Baynes, Dimitri Lague. Statistical modelling of co-seismic knickpoint formation and river response to fault slip. Earth Surface Dynamics, European Geosciences Union, 2019, 7 (3), pp.681-706. 10.5194/esurf-7-681-2019. hal-02202784 HAL Id: hal-02202784 https://hal.archives-ouvertes.fr/hal-02202784 Submitted on 31 Jul 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Earth Surf. Dynam., 7, 681–706, 2019 https://doi.org/10.5194/esurf-7-681-2019 © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License. Statistical modelling of co-seismic knickpoint formation and river response to fault slip Philippe Steer1, Thomas Croissant1,a, Edwin Baynes1,b, and Dimitri Lague1 1Univ Rennes, CNRS, Géosciences Rennes – UMR 6118, 35000 Rennes, France anow at: Department of Geography, Durham University, Durham, UK bnow at: Department of Civil and Environmental Engineering, University of Auckland, Auckland, New Zealand Correspondence: Philippe Steer ([email protected]) Received: 5 February 2019 – Discussion started: 14 February 2019 Revised: 10 June 2019 – Accepted: 3 July 2019 – Published: 24 July 2019 Abstract. -
Usgs Course Sediment Dynamics in the White River Watershed
Coarse Sediment Dynamics in the White River Watershed October 2019 Department of Natural Resources and Parks Water and Land Resources Division King Street Center, KSC-NR-0600 201 South Jackson Street, Suite 600 Seattle, WA 98104 www.kingcounty.gov i Coarse Sediment Dynamics in the White River Watershed Prepared for: King County Water and Land Resources Division Department of Natural Resources and Parks Submitted by: Scott Anderson and Kristin Jaeger U.S. Geological Survey Washington Water Science Center Funded in part by: King County Flood Control District ii iii Acknowledgements This study was partially funded by the King County Flood Control District and was completed with the technical support of King County employees Fred Lott, Judi Radloff, and Chris Brummer; Zac Corum (USACE Seattle); and Dan Johnson (USACE Mud Mountain Dam). Brian Collins improved this study immensely by providing copies of the 1907 Chittenden survey sheets. Thanks to Melissa Foster at Quantum Spatial for helping to acquire extended 2016 lidar coverage and for supplying ancillary data for previous acquisitions. Thanks to Taylor Kenyon and Scott Beason at Mount Rainier National Park for helping provide access and logistics for survey work in the National Park. We thank Brad Goldman of GoldAero for aiding in the collection of aerial imagery. iv Abstract Changes in upstream sediment delivery or downstream base level can cause propagating geomorphic responses in alluvial river systems. Understanding if or how these changing boundary conditions propagate through a watershed is central to understanding changes in channel morphology, flood conveyance and river habitat suitability. Here, we use a large set of high-resolution topographic surveys to assess coarse sediment delivery and routing in the 1,279 km2 glaciated White River, Washington State, USA. -
Multiple Knickpoints in an Alluvial River Generated by a Single Instantaneous Drop in Base Level: Experimental Investigation
Earth Surf. Dynam., 2, 271–278, 2014 Open Access www.earth-surf-dynam.net/2/271/2014/ Earth Surface doi:10.5194/esurf-2-271-2014 © Author(s) 2014. CC Attribution 3.0 License. Dynamics Multiple knickpoints in an alluvial river generated by a single instantaneous drop in base level: experimental investigation A. Cantelli1 and T. Muto2 1Shell International Exploration and Production, Houston, Texas, USA 2Graduate School of Fisheries Science and Environmental Studies, Nagasaki University, 1–14 Bunkyomachi, Nagasaki 852-8521, Japan Correspondence to: A. Cantelli ([email protected]) Received: 6 September 2013 – Published in Earth Surf. Dynam. Discuss.: 17 October 2013 Revised: 5 March 2014 – Accepted: 24 March 2014 – Published: 5 May 2014 Abstract. Knickpoints often form in bedrock rivers in response to base-level lowering. These knickpoints can migrate upstream without dissipating. In the case of alluvial rivers, an impulsive lowering of base level due to, for example, a fault associated with an earthquake or dam removal commonly produces smooth, upstream- progressing degradation; the knickpoint associated with suddenly lowered base level quickly dissipates. Here, however, we use experiments to demonstrate that under conditions of Froude-supercritical flow over an alluvial bed, an instantaneous drop in base level can lead to the formation of upstream-migrating knickpoints that do not dissipate. The base-level fall can generate a single knickpoint, or multiple knickpoints. Multiple knickpoints take the form of cyclic steps, that is, trains of upstream-migrating bedforms, each bounded by a hydraulic jump upstream and downstream. In our experiments, trains of knickpoints were transient, eventually migrating out of the alluvial reach as the bed evolved to a new equilibrium state regulated with lowered base level. -
Knickpoint Formation, Rapid Propagation, and Landscape Response Following Coastal Cliff Retreat at the Last Interglacial Sea-Level Highstand: Kaua‘I, Hawai‘I
Knickpoint formation, rapid propagation, and landscape response following coastal cliff retreat at the last interglacial sea-level highstand: Kaua‘i, Hawai‘i Benjamin H. Mackey†, Joel S. Scheingross, Michael P. Lamb, and Kenneth A. Farley Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA ABSTRACT INTRODUCTION for example, the 5-m.y.-old island of Kaua‘i, Hawai‘i, has modern erosion rates in line with Upstream knickpoint propagation is an Unlike landscapes undergoing continu- those measured over thousands of years and important mechanism for channel incision, ous tectonic uplift, where erosion can balance inferred over millions of years (Gayer et al., and it communicates changes in climate, sea uplift rates, resulting in steady-state topography 2008; Ferrier et al., 2013b). This fi nding sug- level, and tectonics throughout a landscape. (Whipple and Tucker, 1999; Willett et al., 2001), gests island evolution is richer than simple topo- Few studies have directly measured the long- the life cycle of volcanic islands is dominated graphic decay and submergence, and it indicates term rate of knickpoint retreat, however, and by transiently adjusting topography, which has the possibility of persistent high rates of erosion the mechanisms for knickpoint initiation are the potential to better reveal the dominant geo- and local relief generation. debated. Here, we use cosmogenic 3He ex- morphic processes (e.g., Whipple, 2004; Bishop One possible mechanism for local relief posure dating to document the retreat rate et al., 2005; Tucker, 2009; Ferrier et al., 2013a; generation on an actively subsiding landscape of a waterfall in Ka’ula’ula Valley, Kaua‘i, Menking et al., 2013; Ramalho et al., 2013). -
Chapter 5 Rivers
CHAPTER 5 RIVERS 1. INTRODUCTION 1.1 On the continents, except in the most arid regions, precipitation exceeds evaporation. Rivers are the major pathways by which this excess water flows to the ocean. Over the continental United States the average annual rainfall is about 75 centimeters. Of this, about 53 centimeters is returned to the atmosphere by evaporation and transpiration. The remaining 22 centimeters feeds streams and rivers, either directly (by landing in the channels or running off across the surface) or indirectly, by passing through the shallow part of the Earth as groundwater first. This 22 centimeters represents an enormous volume of water: 5.2 x 108 cubic meters per day (1.4 x 1011 gallons per day). 1.2 Rivers are also both the means and the routes by which the products of weathering on the continents are carried to the oceans. Enormous quantities of regolith are produced on the land surface by weathering, and most of this material is transported by rivers to the sea, either as particles or in solution. The other two principal agents that transport this material to the ocean, glaciers and the wind, are minor in comparison. 1.3 Rivers and streams (which term you use is a flexible matter of scale) are channelized flows of water on the Earth’s surface. The term overland flow is used for non-channelized flows of water, usually less than a few centimeters deep but very widespread. There is a pronounced dichotomy between non-channelized flow and channelized flow. Have you ever walked up a small stream channel to see what happens to it? Its termination is almost always well defined.