HIGH RESOLUTION MORPHODYNAMICS and SEDIMENTARY EVOLUTION of ESTUARIES Coastal Systems and Continental Margins
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HIGH RESOLUTION MORPHODYNAMICS AND SEDIMENTARY EVOLUTION OF ESTUARIES Coastal Systems and Continental Margins VOLUME 8 Series Editor Bilal U. Haq Editorial Advisory Board M. Collins, Dept. of Oceanography, University of Southampton, U.K. D. Eisma, Emeritus Professor, Utrecht University and Netherlands Institute for Sea Research, Texel, The Netherlands K.E. Louden, Dept. of Oceanography, Dalhousie University, Halifax, NS, Canada J.D. Milliman, School of Marine Science, The College of William & Mary, Gloucester Point, VA, U.S.A. H.W. Posamentier, Anadarko Canada Corporation, Calgary, AB, Canada A. Watts, Dept. of Earth Sciences, University of Oxford, U.K. The titles published in this series are listed at the end of this volume. High Resolution Morphodynamics and Sedimentary Evolution of Estuaries Edited by Duncan M. FitzGerald Boston University, MA, U.S.A. and Jasper Knight University of Exeter, UK A C.I.P. Catalogue record for this book is available from the Library of Congress. ISBN-10 1-4020-3295-1 (HB) ISBN-13 978-1-4020-3295-0 (HB) ISBN-10 1-4020-3296-X (e-book) ISBN-13 978-1-4020-3296-7 (e-book) Published by Springer, P.O. Box 17, 3300 AA Dordrecht, The Netherlands. www.springeronline.com Cover illustration: View of Nauset Inlet, a small estuarine system located along the outer coast of Cape Cod, Massachusetts. Printed on acid-free paper All Rights Reserved © 2005 Springer No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Printed in the Netherlands. Table of Contents Chapter 1. Towards an understanding of the morphodynamics and sedimentary evolution of Estuaries, Jasper Knight and Duncan M. FitzGerald ........1 Chapter 2. High-resolution geophysical investigations seaward of the Bann estuary, Northern Ireland coast, J. Lyn McDowell, Jasper Knight and Rory Quinn...........................................................................................11 Chapter 3. A seabed classification approach based on multiple acoustic sensors in the Hudson River estuary, Frank O. Nitsche, Suzanne Carbotte, William Ryan and Robin Bell...............................................................33 Chapter 4. Analysis of land-cover shifts in time and their significance, Ramon Gonzalez, João M. Alveirinho Dias, and Óscar Ferreira ....................57 Chapter 5. Comparison of the hydrodynamic character of three tidal inlet systems, Elizabeth A. Pendleton and Duncan M. FitzGerald ..............83 Chapter 6. Suspended sediment fluxes in the middle reach of the Bahia Blanca Estuary, Argentina, Gerardo M. E. Perillo, Jorge O. Pierini, Daniel E. Pérez and M. Cintia Piccolo..........................................................101 Chapter 7. Temporal Variability in Salinity, Temperature and Suspended Sediments in a Gulf of Maine Estuary: Great Bay Estuary, New Hampshire, Larry G. Ward and Frank L. Bub ...................................115 Chapter 8. Morphodynamics and sediment flux in the Blyth estuary, Suffolk, UK, J.R. French, T. Benson and H. Burningham...............................143 Chapter 9. Controls on Estuarine Sediment Dynamics in Merrymeeting Bay, Kennebec River Estuary, Maine, U.S.A., Michael S. Fenster, Duncan M. FitzGerald, Daniel F. Belknap, Brad A. Knisley, Allen Gontz and Ilya V. Buynevich ...............................................................................173 Chapter 10. Coarse-grained sediment transport in northern New England estuaries: a synthesis, Duncan M. FitzGerald, Ilya V. Buynevich, Michael S. Fenster, Joseph T. Kelley and Daniel F. Belknap............195 Chapter 11. Morphodynamic behaviour of a high-energy coastal inlet: Loughros Beg, Donegal, Ireland, Helene Burningham ......................................215 vi Table of Contents Chapter 12. Complex morpho-hydrodynamic response of estuaries and bays to winter storms: north-central Gulf of Mexico, USA, Gregory W. Stone, B. Prasad Kumar, A. Sheremet and Dana Watzke ..................243 Chapter 13. Effects of cold fronts on bayhead delta development: Atchafalaya Bay, Louisiana, USA, Harry H. Roberts, Nan D. Walker, Alexandru Sheremet and Gregory W. Stone ........................................................269 Chapter 14. Evolving understanding of the Tay Estuary, Scotland: Exploring the Linkages Between Frontal Systems and Bedforms, R.W. Duck.........299 Chapter 15. Sedimentological signatures of riverine-dominated phases in estuarine and barrier evolution along an embayed coastline, Ilya V. Buynevich and Duncan M. FitzGerald ...................................315 Chapter 16. Paleodeltas and preservation potential on a paraglacial coast – evolution of eastern Penobscot Bay, Maine, Daniel F. Belknap, Allen M. Gontz and Joseph T. Kelley ..........................................................335 Index .......................................................................................................................361 Chapter 1 TOWARDS AN UNDERSTANDING OF THE MORPHODYNAMICS AND SEDIMENTARY EVOLUTION OF ESTUARIES Jasper Knight1 and Duncan M. FitzGerald2 1Department of Geography, University of Exeter, Rennes Drive, Exeter, Devon, EX4 4RJ, UK, email [email protected] 2Department of Earth Sciences, Boston University, Boston, MA 02015, USA 1. INTRODUCTION Estuaries are found along many of the world’s coastlines irrespective of geological setting, energy regime, and depositional environment (Perillo, 1995a). They also represent one of Earth’s most dynamic sedimentary environments because they lie at the interface of the terrestrial and marine spheres, and evolve in response to the interaction of fluvial, coastal (tidal) and marine (wave) processes. The genetic classification of estuaries has focused on the interaction of processes in these fluvial, coastal, and marine environments (e.g. Perillo, 1995b; Elliott and McLusky, 2002), although in practice the processes influencing estuary morphodynamics vary along the length of the estuary, with tidal state, and over different time-spans. Estuaries are therefore not homogeneous sedimentary systems: their fluvial, coastal and marine environmental regimes are all subject to change in their intrinsic characteristics and their interactions over different scales of time and space, particularly in response to changes in climate and relative sea- 1 D.M. FitzGerald and J. Knight (eds.), High Resolution Morphodynamics and Sedimentary Evolution of Estuaries, 1-9. © 2005 Springer. Printed in the Netherlands. 2 Chapter 1 level (RSL) (Uncles, 2002). It can be argued, therefore, that the estuaries found along present-day coasts worldwide are both environmentally- sensitive and geologically-transient phenomena. It is this sensitivity and transient nature that, in part, make the study of estuaries so important and interesting. Estuary and associated coastal valley- fill sediment successions contain a record of change in the erosional and depositional processes of their fluvial, coastal and marine-associated components. Marginal estuarine and coastal valley-fill sediment successions also record the signatures of transgressive and regressive RSL phases and related changes in coastal sediment depositional patterns. There is a large literature on the morphological characteristics of estuaries and their sedimentary evolution. Notable monographs include those by Dyer (1973, 1986) and Perillo (1995b) and that on tidal inlets by Aubrey and Weishar (1988). These works focus in particular on descriptive studies of individual estuaries, and include conceptual physical models developed to explain estuarine hydraulics, morphology, sedimentary processes and facies distributions in response to a range of external forcing factors. Most of these established physical models stress the traditional view that estuaries are long-term sediment repositories, trapping fluvial sediment as well as bedload sediment from marine sources. More recent studies based on high-resolution field data, however, show that estuaries are more sedimentologically dynamic, often exporting sand to the nearshore or inner shelf (FitzGerald et al. 2000; and summarized by Uncles, 2002). Estuaries that discharge sand are dominated by flood events that overpower normal estuarine circulation and tide-induced sediment transport patterns. This more modern work presents a paradigm shift in the way in which estuaries, and the sedimentary systems of land-sea margins more generally, should be observed, monitored and modeled. Studying the morphodynamics and sedimentary evolution of estuaries is fraught with difficulty. Despite offering an esthetically pleasing and physically diverse environment, data collection in estuaries is often difficult because of poor accessibility; safety problems of traversing exposed tidal flats; treacherous tidal currents and shifting patterns of intertidal creeks; instrumentation problems across the land-sea interface; issues of scale; and the high cost of water-based research. At best, studies can offer only a limited spatial and temporal shapshot of estuary morphodynamic behavior, and make quantitative assessments of sediment fluxes between certain portions of the estuary (Uncles, 2002). Much of estuarine behavior, and response to external forcing factors, therefore remain unknown.