COASTAL SEDIMENT DYNAMICS by LC Van Rijn
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Management of Coastal Erosion by Creating Large-Scale and Small-Scale Sediment Cells
COASTAL EROSION CONTROL BASED ON THE CONCEPT OF SEDIMENT CELLS by L. C. van Rijn, www.leovanrijn-sediment.com, March 2013 1. Introduction Nearly all coastal states have to deal with the problem of coastal erosion. Coastal erosion and accretion has always existed and these processes have contributed to the shaping of the present coastlines. However, coastal erosion now is largely intensified due to human activities. Presently, the total coastal area (including houses and buildings) lost in Europe due to marine erosion is estimated to be about 15 km2 per year. The annual cost of mitigation measures is estimated to be about 3 billion euros per year (EUROSION Study, European Commission, 2004), which is not acceptable. Although engineering projects are aimed at solving the erosion problems, it has long been known that these projects can also contribute to creating problems at other nearby locations (side effects). Dramatic examples of side effects are presented by Douglas et al. (The amount of sand removed from America’s beaches by engineering works, Coastal Sediments, 2003), who state that about 1 billion m3 (109 m3) of sand are removed from the beaches of America by engineering works during the past century. The EUROSION study (2004) recommends to deal with coastal erosion by restoring the overall sediment balance on the scale of coastal cells, which are defined as coastal compartments containing the complete cycle of erosion, deposition, sediment sources and sinks and the transport paths involved. Each cell should have sufficient sediment reservoirs (sources of sediment) in the form of buffer zones between the land and the sea and sediment stocks in the nearshore and offshore coastal zones to compensate by natural or artificial processes (nourishment) for sea level rise effects and human-induced erosional effects leading to an overall favourable sediment status. -
Natural and Anthropogenic Influences on the Morphodynamics of Sandy and Mixed Sand and Gravel Beaches Tiffany Roberts University of South Florida, [email protected]
University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School January 2012 Natural and Anthropogenic Influences on the Morphodynamics of Sandy and Mixed Sand and Gravel Beaches Tiffany Roberts University of South Florida, [email protected] Follow this and additional works at: http://scholarcommons.usf.edu/etd Part of the American Studies Commons, Geology Commons, and the Geomorphology Commons Scholar Commons Citation Roberts, Tiffany, "Natural and Anthropogenic Influences on the Morphodynamics of Sandy and Mixed Sand and Gravel Beaches" (2012). Graduate Theses and Dissertations. http://scholarcommons.usf.edu/etd/4216 This Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Natural and Anthropogenic Influences on the Morphodynamics of Sandy and Mixed Sand and Gravel Beaches by Tiffany M. Roberts A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Geology College of Arts and Sciences University of South Florida Major Professor: Ping Wang, Ph.D. Bogdan P. Onac, Ph.D. Nathaniel Plant, Ph.D. Jack A. Puleo, Ph.D. Julie D. Rosati, Ph.D. Date of Approval: July 12, 2012 Keywords: barrier island beaches, beach morphodynamics, beach nourishment, longshore sediment transport, cross-shore sediment transport. Copyright © 2012, Tiffany M. Roberts Dedication To my eternally supportive mother, Darlene, my brother and sister, Trey and Amber, my aunt Pat, and the friends who have been by my side through every challenge and triumph. -
Part III-2 Longshore Sediment Transport
Chapter 2 EM 1110-2-1100 LONGSHORE SEDIMENT TRANSPORT (Part III) 30 April 2002 Table of Contents Page III-2-1. Introduction ............................................................ III-2-1 a. Overview ............................................................. III-2-1 b. Scope of chapter ....................................................... III-2-1 III-2-2. Longshore Sediment Transport Processes ............................... III-2-1 a. Definitions ............................................................ III-2-1 b. Modes of sediment transport .............................................. III-2-3 c. Field identification of longshore sediment transport ........................... III-2-3 (1) Experimental measurement ............................................ III-2-3 (2) Qualitative indicators of longshore transport magnitude and direction ......................................................... III-2-5 (3) Quantitative indicators of longshore transport magnitude ..................... III-2-6 (4) Longshore sediment transport estimations in the United States ................. III-2-7 III-2-3. Predicting Potential Longshore Sediment Transport ...................... III-2-7 a. Energy flux method .................................................... III-2-10 (1) Historical background ............................................... III-2-10 (2) Description ........................................................ III-2-10 (3) Variation of K with median grain size................................... III-2-13 (4) Variation of K with -
The Relationship Between Wave Action and Beach Profile Characteristics
CHAPTER 14 THE RELATIONSHIP BETWEEN WAVE ACTION AND BEACH PROFILE CHARACTERISTICS P. H. Kemp Department of GivH Engineering. University College London, England. ABSTRACT. The rational design of coast protection works requires a knowledge of the behaviour of the beach under natural conditions. The understanding of the relationship between the waves acting on the beach and the characteristics of the beach profile produced, is thus a necessary preliminary to the analysis of the causes of beach erosion and the evaluation of the effect of projected remedial measures. The present paper describes the results of a series of prelimin- ary hydraulic model experiments carried out by the author prior to a model study of the behaviour of groynes in stabilising beaches. Most of the beach materials used represented coarse sand or shingle in nature. The results demonstrate the fundamental importance of the "phase- difference" in terms of wave period between the break-point and the limit of uprush, in relation to flow conditions, cusp formation, and the change from "step" to "bar" type profiles. Within the limits of the experiments an expression connecting the breaker height, beach profile length, and grain diameter is developed, and its implications examined in relation to beach slope, and to the previous "wave steepness" criterion for the change from step to bar type profiles. Observations are included on the rate of recession of a shore- line due to the onset of more severe wave conditions. INTRODUCTION. BEACH CHANGES. Changes in the coastline may be classified as:- (1) Progressive changes resulting in prograding or recession of the shoreline over a long period of time. -
BUIL])ING STON.E O·F WASHINGTON
BUIL])ING STON.E o·f WASHINGTON By WAYNE S. MOEN Washington Department of Conservation Division of Mines and Geology Bulletin No. 55 1967 State of Washington DANIEL J. EV ANS, Governor Department of Conservation H. MAURICE AHLQUIST, Director DIVISION OF MINES AND GEOLOGY MARSHALL T. HUNTTING, Supervisor Bulletin No. 55 BUILDING STONE OF WASHINGTON By WAYNE S. MOEN STATE PRINTING PLANT. OLYMPI A , WASHINGTON 1967 For sale by Department Pof? ceConsl]SliARYervation, Olympia, Washington. PACIFIC NORTHWEST FOREST AND RANGE EXPERIMENT STATION etnDTLAND. OR£00N CONTENTS Poge Introduction 7 General history .. ...... ...........................•............ 8 Production and vo lue . 10 Forms of building stone . 12 Field stone . 12 Rough building stone . 13 Rubble . • . 14 Flogging (flagstone) . 14 Ashlar . .. ......... ........ , ................. , . , . 15 Crushed stone . 16 Terrozzo . 17 Roofing granules.............. .... ..... ......... 18 Exposed aggregate . 18 Reconstituted stone . • . 19 Landscape rock . 20 Area coverage of bui Iding stone . 21 Acquisition of bui )ding stone . 22 Examination of stone deposits . 23 General quarrying methods . 24 Physical properties of building stone . 26 Strength . 26 Hardness and workabi Iity . • . 27 Color . 28 Alteration ....•...................... , ........... , . 29 Porosity and absorption ...........•. : . 31 Testing of building stone... .. .................... ................ 33 Common building stones of Washington . 34 Granite . 35 Geology and distribution . 35 Physical properties . 38 Varieties -
Pocket Beach Hydrodynamics: the Example of Four Macrotidal Beaches, Brittany, France
Marine Geology 266 (2009) 1–17 Contents lists available at ScienceDirect Marine Geology journal homepage: www.elsevier.com/locate/margeo Pocket beach hydrodynamics: The example of four macrotidal beaches, Brittany, France A. Dehouck a,⁎, H. Dupuis b, N. Sénéchal b a Géomer, UMR 6554 LETG CNRS, Université de Bretagne Occidentale, Institut Universitaire Européen de la Mer, Technopôle Brest Iroise, 29280 Plouzané, France b UMR 5805 EPOC CNRS, Université de Bordeaux, avenue des facultés, 33405 Talence cedex, France article info abstract Article history: During several field experiments, measurements of waves and currents as well as topographic surveys were Received 24 February 2009 conducted on four morphologically-contrasted macrotidal beaches along the rocky Iroise coastline in Brittany Received in revised form 6 July 2009 (France). These datasets provide new insight on the hydrodynamics of pocket beaches, which are rather poorly Accepted 10 July 2009 documented compared to wide and open beaches. The results notably highlight a cross-shore gradient in the Available online 18 July 2009 magnitude of tidal currents which are relatively strong offshore of the beaches but are insignificant inshore. Communicated by J.T. Wells Despite the macrotidal setting, the hydrodynamics of these beaches are thus totally wave-driven in the intertidal zone. The crucial role of wind forcing is emphasized for both moderately and highly protected beaches, as this Keywords: mechanism drives mean currents two to three times stronger than those due to more energetic swells when beach morphodynamics winds blow nearly parallel to the shoreline. Moreover, the mean alongshore current appears to be essentially embayed beach wind-driven, wind waves being superimposed on shore-normal oceanic swells during storms, and variations in beach cusps their magnitude being coherent with those of the wind direction. -
Part 629 – Glossary of Landform and Geologic Terms
Title 430 – National Soil Survey Handbook Part 629 – Glossary of Landform and Geologic Terms Subpart A – General Information 629.0 Definition and Purpose This glossary provides the NCSS soil survey program, soil scientists, and natural resource specialists with landform, geologic, and related terms and their definitions to— (1) Improve soil landscape description with a standard, single source landform and geologic glossary. (2) Enhance geomorphic content and clarity of soil map unit descriptions by use of accurate, defined terms. (3) Establish consistent geomorphic term usage in soil science and the National Cooperative Soil Survey (NCSS). (4) Provide standard geomorphic definitions for databases and soil survey technical publications. (5) Train soil scientists and related professionals in soils as landscape and geomorphic entities. 629.1 Responsibilities This glossary serves as the official NCSS reference for landform, geologic, and related terms. The staff of the National Soil Survey Center, located in Lincoln, NE, is responsible for maintaining and updating this glossary. Soil Science Division staff and NCSS participants are encouraged to propose additions and changes to the glossary for use in pedon descriptions, soil map unit descriptions, and soil survey publications. The Glossary of Geology (GG, 2005) serves as a major source for many glossary terms. The American Geologic Institute (AGI) granted the USDA Natural Resources Conservation Service (formerly the Soil Conservation Service) permission (in letters dated September 11, 1985, and September 22, 1993) to use existing definitions. Sources of, and modifications to, original definitions are explained immediately below. 629.2 Definitions A. Reference Codes Sources from which definitions were taken, whole or in part, are identified by a code (e.g., GG) following each definition. -
Descriptions of Common Sedimentary Environments
Descriptions of Common Sedimentary Environments River systems: . Alluvial Fan: a pile of sediment at the base of mountains shaped like a fan. When a stream comes out of the mountains onto the flat plain, it drops its sediment load. The sediment ranges from fine to very coarse angular sediment, including boulders. Alluvial fans are often built by flash floods. River Channel: where the river flows. The channel moves sideways over time. Typical sediments include sand, gravel and cobbles. Particles are typically rounded and sorted. The sediment shows signs of current, such as ripple marks. Flood Plain: where the river overflows periodically. When the river overflows, its velocity decreases rapidly. This means that the coarsest sediment (usually sand) is deposited next to the river, and the finer sediment (silt and clay) is deposited in thin layers farther from the river. Delta: where a stream enters a standing body of water (ocean, bay or lake). As the velocity of the river drops, it dumps its sediment. Over time, the deposits build further and further into the standing body of water. Deltas are complex environments with channels of coarser sediment, floodplain areas of finer sediment, and swamps with very fine sediment and organic deposits (coal) Lake: fresh or alkaline water. Lakes tend to be quiet water environments (except very large lakes like the Great Lakes, which have shorelines much like ocean beaches). Alkaline lakes that seasonally dry up leave evaporite deposits. Most lakes leave clay and silt deposits. Beach, barrier bar: near-shore or shoreline deposits. Beaches are active water environments, and so tend to have coarser sediment (sand, gravel and cobbles). -
Sandstone Problems
CONSERVATION TALK Michael Trinkley Why Sandstone Monuments Have So Many Problems Whether in the Carolinas, Utah or Massachusetts biggest cause is the effect of moisture, brought on by many sandstone are in very poor condition. Why? And capillary action, humidity and even a monument's perhaps even more importantly, what can be done? environment and micro-climate. Sources not related to Sandstone is a sedimentary rock, meaning that moisture include solar and UV radiation, as well as minerals or organic particles have settled in layers and the structural issues-although I don't believe any of these layers have gradually formed into rock. They often (but not are as important as moisture. Contributing to the always) have distinct bedding planes-or layers. Geologists problems caused by moisture are salts and air pollution. generally divided sedimentary rocks into three categories So let's look at a few of the more common problems. and most of what we see in cemeteries may be classified as Keep in mind that relatively little conservation research "clastic." These are formed by the accumulation of has been conducted concerning these problems, so there mechanically distintegrated rocks that are cemented remains much debate-and few simple answers. together. Air pollution can cause what are known as Sandstones are composed of quartz, feldspar, silicates, pollution crusts-often hard and brittle, leaving the stone mica, hornblende, and clay minerals that are cemented with beneath soft, friable, and disaggregating. They may also either siliceous or carbonate/calcite cement (see Table 1). It be known as carbon deposits. Found in urban settings is largely these cementing materials that affect the they are formed from pollution products, including longevity of one sandstone over another. -
Lecture 12: Coasts
Ediz Hook, Port Angeles ESCI 321 announcements • Problem set 2 due tonight at midnight • Exam 2 in one week • We will have a major review session next Thursday. Come with questions. • Study guide posted. Bring to class on Thursday Coasts, beaches and estuaries I. Coast formation II. Beaches: Rivers of sand III. Estuaries http://www.nps.gov/olym/naturescience/damremovalblog.htm 1 Processes determining coastal morphology and formation Beach morphology Plate tectonics Sea level changes (eustatic and relative sea level change) Glaciers Weathering Wave action and storms Maine N.C. General scheme of coastline development (primary → secondary) Seasonal changes in beach morphology Longshore sediment transport How do waves affect beaches? (Beach movie) 2 Tombolo on the shore of Lake Erie, Erie, Pennsylvania Formation of rip currents and beach cusps Sediment composing barrier Islands along the east coast of the U.S. is continuously eroding and depositing toward the continent and toward the south. Swash on beach cusps at Propriano, Corsica. (Photo: Sogreah, France) Rip currents on a New Zealand beach 3 Dune Ridge Beach Open Ocean Puget Sound coastlines Lagoon Marsh Flat Lagoonal Peat Common types of shorelines in Puget Sound Natural shoreline with development •Sand and gravel •Sandy beach/dunes •Sediment-starved beach •Mudflats •Deltas •Beach w/ bulkheads 4 Shoreline with bulkhead Effects of beach armoring on amphipod habitat, Paihia, New Zealand Forage fish spawning grounds in Bellingham Bay • Surf smelt spawn in upper intertidal zone • In Bellingham -
RICHARD J. RUSSELL WILLIAM G. Mcintire Coastal Studies Institute, Louisiana State University, Baton Rouge, La. Beach Cusps Abstr
RICHARD J. RUSSELL Coastal Studies Institute, Louisiana State University, Baton Rouge, La. WILLIAM G. McINTIRE Beach Cusps Abstract: Beach cusps develop along seaward faces posure and state of the sea. Conditions under which of growing berms. They appear early in the transi- cusps disappear are described. Although most steps tional period of decreasing wave energy from in the depositional development and erosional winter- to summer-beach conditions. Growth stages removal of cusps are understood, the theory of their are described and related to currents within the origin will remain incomplete until the reasons for swash zone. Cusp spacing depends on coastal ex- their spacing are known in quantitative terms. CONTENTS Introduction and acknowledgments 307 3. Number of examples in spacing of cusp apices . 311 Field observations 308 4. Beach changes related to increasing and decreas- Juvenile cusps 311 ing wave energy 315 Well-developed cusps 312 5. Sequential stages of turbidity distribution and Cusp disappearance 312 current flow associated with growing cusps 316 Toward a theory of cusp origin 313 References cited 318 Plate Following Appendix 1. Relationship between apex and bay 1. Cusps on firm beaches slopes 319 2. Juvenile cusps Appendix 2. Relationship of cusp length to de- 3. Well-developed cusps gree of exposure 319 4. Cusp erosion, Preston Beach, south of Perth, Western Australia r-316 Figure 5. Asymmetrical erosion of cusps, Dominica . 1. Section across three series of cusps: Cluny, Basse 6. Cusp-originating processes Terre, Guadeloupe 309 7. Current flow into bays, Warnbro Sound, south 2. Comparison between bay and apex slopes . 310 of Safety Bay, Western Australia ment and formulating opinions about their INTRODUCTION AND histories, we turned to the literature, usually ACKNOWLEDGMENTS finding confusion at least as great as our own Our beach-cusp observations started in the during initial stages of investigation. -
45. Sedimentary Facies and Depositional History of the Iberia Abyssal Plain1
Whitmarsh, R.B., Sawyer, D.S., Klaus, A., and Masson, D.G. (Eds.), 1996 Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 149 45. SEDIMENTARY FACIES AND DEPOSITIONAL HISTORY OF THE IBERIA ABYSSAL PLAIN1 D. Milkert,2 B. Alonso,3 L. Liu,4 X. Zhao,5 M. Comas,6 and E. de Kaenel4 ABSTRACT During Leg 149, a transect of five sites (Sites 897 to 901) was cored across the rifted continental margin off the west coast of Portugal. Lithologic and seismostratigraphical studies, as well as paleomagnetic, calcareous nannofossil, foraminiferal, and dinocyst stratigraphic research, were completed. The depositional history of the Iberia Abyssal Plain is generally characterized by downslope transport of terrigenous sedi- ments, pelagic sedimentation, and contourite sediments. Sea-level changes and catastrophic events such as slope failure, trig- gered by earthquakes or oversteepening, are the main factors that have controlled the different sedimentary facies. We propose five stages for the evolution of the Iberia Abyssal Plain: (1) Upper Cretaceous and lower Tertiary gravitational flows, (2) Eocene pelagic sedimentation, (3) Oligocene and Miocene contourites, (4) a Miocene compressional phase, and (5) Pliocene and Pleistocene turbidite sedimentation. Major input of terrigenous turbidites on the Iberia Abyssal Plain began in the late Pliocene at 2.6 Ma. INTRODUCTION tured by both Mesozoic extension and Eocene compression (Pyrenean orogeny) (Boillot et al., 1979), and to a lesser extent by Miocene com- Leg 149 drilled a transect of sites (897 to 901) across the rifted mar- pression (Betic-Rif phase) (Mougenot et al., 1984). gin off Portugal over the ocean/continent transition in the Iberia Abys- Previous studies of the Cenozoic geology of the Iberian Margin sal Plain.