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    Principles of Tidal Sedimentology

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    Richard A. Davis, Jr. Robert W. DalrympleEditors

    Principles of TidalSedimentology

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    EditorsRichard A. Davis, Jr.Harte Research InstituteTexas A&M UniversityOcean Drive 6300Corpus Christi, TX 78412USA

    Coastal Research LaboratoryDepartment of GeologyUniversity of South FloridaTampa, FL [email protected]

    Robert W. DalrympleDepartment of Geological Sciences andGeological EngineeringQueens UniversityMiller HallKingston, ON K7L 3N6

    [email protected]

    ISBN 978-94-007-0122-9 e-ISBN 978-94-007-0123-6DOI 10.1007/978-94-007-0123-6Springer Dordrecht Heidelberg London New York

    Library of Congress Control Number: 2011939475

    Springer Science+Business Media B.V. 2012No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by anymeans, electronic, mechanical, photocopying, microfilming, recording or otherwise, without writtenpermission from the Publisher, with the exception of any material supplied specifically for the purpose ofbeing entered and executed on a computer system, for exclusive use by the purchaser of the work.

    Cover illustration: Fig. 5.13 (upper part) from this book.

    Printed on acid-free paper

    Springer is part of Springer Science+Business Media (www.springer.com)

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    v

    Tides have fascinated humans for millennia. Their regularity and their apparent

    correlation with lunar behavior intrigued natural philosophers, even the Greeks, who

    live on an essentially tideless sea although there are strong tidal currents in localized

    constrictions. Apparently, they learned about tides from areas outside the Straits of

    Gibralter and from the Arabs who experienced significant tides in the Persian Gulf.

    From a practical perspective, tidal changes in water elevation and the currents

    associated with these changes were of great importance for shipping and militarypurposes. In areas such as the countries surrounding the southern North Sea, such

    considerations required accurate tidal predictions, which in turn drew the attention of

    some of the greatest astronomers and mathematicians.

    Among the notable individuals who devoted at least part of their careers to the

    study of tides, and have contributed to our understanding of them are Galileo,

    Descartes, Bacon, Kepler, Euler, Laplace, and Lord Kelvin (Cartwight 1999). Indeed,

    many of the widely used mathematical techniques that we now take for granted were

    developed to help understand the behavior of the tides. More recently, interest in tides

    and storm surges has been fostered by the need to protect ever-increasing coastal

    population centers from catastrophic inundation, and by the desire to reclaim tidal

    flats for agricultural and industrial purposes. Foremost in this activity have been TheNetherlands, Germany, and adjacent parts of Denmark.

    Research on the nature of tidal deposits has been underway for about 50 years.

    Early studies on the Wadden Sea along the North Sea coast of The Netherlands and

    Germany were among the original landmark efforts in this area (e.g. van Straaten

    1954; Postma 1961; Reineck 1963), and were followed closely by work in England

    (Evans 1965) and France (Bajard 1966). Such efforts were driven by the dual need to

    understand the coastal zone for the protection of population centers and to provide an

    actualistic analog for ancient sedimentary successions. In North America, Kleins

    work on the Bay of Fundy (Klein 1963) initiated detailed efforts in that part of the

    world. The early German work in the North Sea had a major biological and ichno-

    logical component, a topic that was pursued systematically at the Skidaway Institute

    of Oceanography in the southeastern United States (e.g. Frey and Howard 1969).

    Despite having some of the most widespread tidal flats in the world, work along the

    Chinese coast was relatively slow to develop, although there were notable early studies

    (e.g. Wang 1963). In the carbonate realm, pioneering studies were conducted on the

    tidal flats of Andros Island, the Bahamas (e.g. Shinn et al. 1969), and the Persian Gulf

    (Evans et al. 1969).

    In spite of important work on the shallow-marine tidal deposits in the seas of

    northwestern Europe (e.g. Stride 1963), most of the early work on modern tidal

    Preface

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    vi Preface

    deposits was devoted to study of intertidal environments, mainly because they were

    readily accessible. This fixation on the intertidal zone is perhaps nowhere more

    evident in the influential compilation of examples contained in the book Tidal

    Deposits: A Casebook of Recent Examples and Fossil Counterparts(Ginsburg 1975).

    Indeed, the upward-fining succession developed by the progradation of a tidal flat

    was among the very first facies models created. Application of these studies to the

    rock record was widespread in the carbonate literature, with numerous documentedexamples being published through the 1960s, 1970s and 1980s. By comparison, the

    extension of the work on the modern tidal deposits to ancient siliciclastic successions

    was slow. At least one impediment to the widespread application to the ancient was

    the notion put forward by Irwin (1965), and since largely disproven, at least for

    siliciclastic sediments, that the expansive epicontinental seas of the past were largely

    tideless, as a result of frictional damping of the tidal wave. An even greater impedi-

    ment was the lack of definitive criteria for the recognition of tidal deposits, given that

    exposure indicators are much less easily preserved in siliciclastic tidal deposits than

    they are in carbonates. Thus, a milestone in the study of tidal deposits occurred in

    1980 with the publication by Visser (1980) of tidal bundles in cross beds formed by

    subaqueous dunes, which provided the first documentation of a definitive indicator oftidal sedimentation, spawned the widespread recognition of ancient tidal deposits in

    an ever-growing number of localities.

    Gradually, the focus of research on modern tidal environments has shifted away

    from tidal flats, toward a more comprehensive examination of tidal sedimentation in

    a wide range of settings, including even the deep ocean. Studies have tended to become

    more holistic in their treatment of entire depositional systems, rather than concentrating

    on only one part (e.g. tidal flats) of the whole. This more comprehensive approach is

    evident in many of the papers in this volume.

    Because of the increasing attention given to tidal deposits it became important to

    organize a uniform nomenclature and approach to their study. As a consequence, Robert

    N. Ginsburg organized and hosted a conference of interested researchers in February of1973. It included field experiences in both siliciclastic (Sapelo Island, Georgia, USA)

    and carbonate areas (Florida Keys, USA and the Bahamas), followed by presentations

    of research on tidalites (a term coined by George deVries Klein (1971)) by all in

    attendance. The next similar conference was held in The Netherlands in 1986, followed

    in regular succession by a series International Conferences on Tidal Sedimentology that

    has met in Calgary, Canada (1989), Wilhelmshaven, Germany (1992), Savannah,

    Georgia USA (1996), Seoul, Korea (2000), Copenhagen, Denmark (2004) and, most

    recently, in Qingdao, China (2008). The next meeting will be in Caen, France in 2012.

    The meeting in 2008 in China was particularly stimulating with an attendance that

    surpassed any previous meeting. The expansion of interest in tidal deposits appears to

    be spurred by two factors: the need to understand coastal tidal environments in order

    to predict how these sensitive environments might respond to sea-level rise and

    climate change; and providing data and interpretations to help in understanding

    ancient depositional environments that were influenced by tides. Davis thought it was

    a good time to assemble a principles-type volume on the topic of tidal sedimentology

    given that no such synthesis exists, and because there has been so much new research

    on tidal environments and deposits over the last few years. Dalrymple agreed to be

    co-editor and the result of their efforts is this volume.

    The purpose of this volume is to provide the first-ever, high-level overview of tidal

    sedimentology. Many of the chapters contain the first-ever synthesis of information

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    viiPreface

    on the particular topic! The approach is comprehensive with state-of-the-art reviews

    of the full spectrum of tidal depositional environments, from supratidal salt marshes,

    through the full range of coastal environments and continental shelves, to the deep

    sea. Examples from modern environments and ancient deposits are provided, and

    both siliciclastic and carbonate environments are discussed. The book is organized in

    the following four parts. (1) Chapters 14 provide overviews of the fundamentals of:

    the generation of tides, the nature of sediment transport by tidal currents, the criteriaby which tidal deposits can be recognized, and the ichnology of tidal deposits. The

    later chapter represents the first time that the ichnological characteristics of tidal depo-

    sits have been reviewed systematically. (2) Chapters 514 review the characteristics

    of the full range of siliciclastic tidal environments, including both tide-dominated

    estuaries and deltas, as well as the various tidal components of barrier-lagoon systems.

    These chapters cover all aspects of the sedimentology of these environments, from

    the details of the physical processes operating in them, through the morphodynamics

    and facies, and the stratigraphic organization of the deposits. (3) Chapters 1518

    provide syntheses of particular times and places in earth history where tidal deposits

    are particularly notable. The chapter on the Precambrian reviews tidal sedimentation

    at a time when the Moon was significantly closer to the Earth and the tide-generatingforce should have been stronger. The reviews of the tidal deposits in the Illinois Basin

    (Carboniferous age), Western Interior Seaway (Cretaceous) and Spanish Pyrenean Basin

    (Eocene) provide unique insights into the large-scale (tectonic and relative sea level)

    controls on the spatial and temporal distribution of tidal sedimentation. (4) Chapters

    1921 discuss tidal sedimentation in modern and ancient carbonate environments.

    Experts from throughout the world have been chosen to be the lead authors on

    each of the chapters. They and their co-authors build on their considerable personal

    experience to present insightful syntheses of the latest research in the particular topic.

    Each chapter has abundant illustrations, many of which are in color to enhance their

    effectiveness. References are extensive and include historically important ones as

    well as those on the leading edge of each topic.Because of the uniquely broad coverage within each of the chapters, and in the

    volume as a whole, this book should be of value to a wide range of researchers. Workers

    who study modern sedimentary environments, and especially coastal settings, including

    environmental managers and coastal engineers, will find much about the dynamics of

    these environments that will assist them to develop protection strategies that are

    compatible with the natural behavior of these complex systems, including their

    response to potentially rising sea level. Geologists who study ancient sedimentary

    successions, whether for more academic or more applied reasons, will find a wealth

    of information about the behavior of tidal environments, ranging from the nature of

    the facies, through small-scale sedimentary successions, to the largest-scale sequence-

    stratigraphic control on tidal sedimentation.

    The editors and authors gratefully acknowledge the financial support of numerous

    funding agencies that have provided support for their respective research activities.

    They also thank the people who have provided excellent and constructive reviews

    (see below). The editors appreciate the cooperation of Dr. Robert Doe and his staff at

    Springer Publishers.

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    viii Preface

    Chapter Reviewers

    Clark Alexander

    Serge Bern

    Sean Bingham

    Ron BoydMargie Chan

    Kyungsik Choi

    Poppe de Boer

    Robert Dott

    Paul Enos

    Jon French

    Shu Gao

    Murray Gingras

    Liviu Giosan

    Steven Greb

    Gary Hampson

    Steve Hasiotis

    Christopher Kendall

    George Klein

    Erik Kvale

    Tim Lawton

    Don McNeil

    Bruce Nocita

    Nora Noffke

    David PiperPiret Plink-Bjorklund

    Brian Pratt

    Denise Reed

    Joshiki Saito

    Gene Shanmugam

    Gene Shinn

    Ronald Steel

    John Suter

    S. Temmerman

    Bernadette Tessier

    Ad van der Spek

    Grant Wach

    Ping Wang

    Colin Woodruff

    Paul Wright

    References

    Bajard J (1966) Figure et structures sdimentaires dans la partie orientale de la baie de MontSaint-Michel. Rev Geog Phys Geol Dyn 8:39112

    Cartwright DE (1999) Tides: a scientific history. Cambridge University Press, Cambridge, 292 pEvans G (1965) Intertidal flat sediments and their environments of deposition in The Wash. J Geol

    Soc Lond 121:209245Evans G, Schmidt V, Bush P, Nelson H (1969) Stratigraphy and geologic history of the Sabkha,

    Persian Gulf. Sedimentology 12:145159Frey RW, Howard JD (1969) A profile of biogenic sedimentary structures in a Holocene barrier

    island-salt marsh complex, Georgia. Gulf Coast Assoc Geol Soc Trans 19:427444Ginsburg RN (1956) Environmental relationships of grain size and constituent particles in some

    south Florida carbonate sediments. Bull Am Assoc Petrol Geol 40:23842427

    Ginsburg RN (1975) Tidal deposits: a casebook of recent examples and fossil counterparts. Springer,New York, 426 p

    Irwin ML (1965) General theory of epeiric clear water sedimentation. Bull Am Assoc Petrol Geol49: 445459

    Klein deV G (1971) A sedimentary model for determining paleotidal range. Geol Soc Am Bull82:25852592

    Postma H (1961) Transport and accumulation of suspended matter in the Dutch Wadden Sea. NethJ Sea Res 1:148190

    Reineck H-R (1963) Sedimentgefge im Bereich der sdlichen Nordsee. Abhandl SenckenberNaturforsch Ges 505:1138

    Shinn EA, Lloyd RM, Ginsburg RN (1969) Anatomy of a modern carbonate tidal flat, Andros Island,Bahamas. J Sediment Petrol 39:112123

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    ixPreface

    Stride AH (1963) Current-swept sea floors near the southern half of Great Britain. Q J Geol SocLond 119:175199

    van Straaten LMJU (1954) Composition and structure of recent marine sediments in the Netherlands.Leidse Geol Mededel 19:1110

    Visser MJ (1980) Neap-spring cycles reflected in Holocene subtidal large-scale bedform deposits: apreliminary note. Geology 8:543546

    Wang Y (1963) The coastal dynamic geomorphology of the northern Bohai Bay. In: Wang Y (ed)

    Collected oceanic works of Nanjing University. Nanjing University Press, Nanjing (in Chinesewith English abstract)

    Corpus Christi, Texas USA

    Kingston, Ontario, Canada

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    xi

    Contents

    1 Tidal Constituents of Modern and Ancient

    Tidal Rhythmites: Criteria for Recognition and Analyses. . . . . . . . . . 1

    Erik P. Kvale

    2 Principles of Sediment Transport Applicable

    in Tidal Environments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

    Ping Wang 3 Tidal Signatures and Their Preservation

    Potential in Stratigraphic Sequences. . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

    Richard A. Davis, Jr.

    4 Tidal Ichnology of Shallow-Water Clastic Settings . . . . . . . . . . . . . . 57

    Murray K. Gingras and James A. MacEachern

    5 Processes, Morphodynamics,

    and Facies of Tide-Dominated Estuaries . . . . . . . . . . . . . . . . . . . . . . . . 79

    Robert W. Dalrymple, Duncan A. Mackay,

    Aitor A. Ichaso, and Kyungsik S. Choi

    6 Stratigraphy of Tide-Dominated Estuaries . . . . . . . . . . . . . . . . . . . . . . 109

    Bernadette Tessier

    7 Tide-Dominated Deltas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

    Steven L. Goodbred, Jr. and Yoshiki Saito

    8 Salt Marsh Sedimentation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

    Jesper Bartholdy

    9 Open-Coast Tidal Flats. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187

    Daidu Fan

    10 Siliciclastic Back-Barrier Tidal Flats . . . . . . . . . . . . . . . . . . . . . . . . . . . 231Burghard W. Flemming

    11 Tidal Channels on Tidal Flats

    and Marshes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269

    Zoe J. Hughes

    12 Morphodynamics and Facies Architecture

    of Tidal Inlets and Tidal Deltas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301

    Duncan FitzGerald, Ilya Buynevich, and Christopher Hein

    13 Shallow-Marine Tidal Deposits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335

    Jean-Yves Reynaud and Robert W. Dalrymple

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    xii Contents

    14 Deep-Water Tidal Sedimentology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371

    Mason Dykstra

    15 Precambrian Tidal Facies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397

    Kenneth A. Eriksson and Edward Simpson

    16 Hypertidal Facies from the Pennsylvanian Period:

    Eastern and Western Interior Coal Basins, USA. . . . . . . . . . . . . . . . . . 421Allen W. Archer and Stephen F. Greb

    17 Tidal Deposits of the Campanian Western

    Interior Seaway, Wyoming, Utah and Colorado, USA . . . . . . . . . . . . . 437

    Ronald J. Steel, Piret Plink-Bjorklund, and Jennifer Aschoff

    18 Contrasting Styles of Siliciclastic Tidal Deposits

    in a Developing Thrust-Sheet-Top Basins The Lower

    Eocene of the Central Pyrenees (Spain). . . . . . . . . . . . . . . . . . . . . . . . . 473

    A.W. Martinius

    19 Holocene Carbonate Tidal Flats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 507Eugene C. Rankey and Andrew Berkeley

    20 Tidal Sands of the Bahamian Archipelago. . . . . . . . . . . . . . . . . . . . . . . 537

    Eugene C. Rankey and Stacy Lynn Reeder

    21 Ancient Carbonate Tidalites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 567

    Yaghoob Lasemi, Davood Jahani, Hadi Amin-Rasouli,

    and Zakaria Lasemi

    Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 609

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    xiii

    Contributors

    Hadi Amin-Rasouli Department of Geosciences, University of Kurdistan, Sanandaj,

    Iran, [email protected]

    Allen W. Archer Department of Geology, Kansas State University, Manhattan, KS

    66506, USA, [email protected]

    Jennifer Aschoff Department of Geology and Geologic Engineering, Colorado

    School of Mines, Golden, CO, USA, [email protected]

    Jesper Bartholdy Department of Geography and Geology, University of Copenhagen,

    10 ster Voldgade, Copenhagen DK-3050, Denmark, [email protected]

    Andrew Berkeley Department of Evironmental & Geographical Sciences,

    Manchester Metropolitan University, John Dalton Extension Building, Chester

    Street, Manchester M1 5GD, UK

    Ilya Buynevich Department of Earth and Environmental Sciences, Temple

    University, 313 Philadelphia, PA 19122, USA, [email protected]

    Kyungsik S. Choi Faculty of Earth Systems and Environmental Sciences, Chonnam

    National University, Gwangju 500-757, South Korea, [email protected]

    Robert W. Dalrymple Department of Geological Sciences and Geological

    Engineering, Queens University, Kingston, ON K7L 3N6, Canada, dalrymple@geol.

    queensu.ca

    Richard A. Davis, Jr. Department of Geology, Coastal Research Laboratory,

    University of South Florida, Tampa, FL 33620, USA, [email protected]

    Harte Research Institute for Gulf of Mexico Studies, Texas A&M University

    Corpus Christi, TX 78412, USA

    Mason Dykstra Department of Geology and Geological Engineering, Colorado

    School of Mines, Golden, CO 80401, USA, [email protected]

    Kenneth A. Eriksson Department of Geosciences, Virginia Tech, Blacksburg,

    VA 24061, USA, [email protected]

    Daidu Fan State Key Laboratory of Marine Geology, Tongji University, Shanghai

    200092, China, [email protected]

    Duncan FitzGerald Department of Earth Sciences, Boston University, Boston, MA

    02215, USA, [email protected]

    Burghard W. Flemming Senckenberg Institute, Suedstrand 40, 26382 Wilhelmshaven,

    Germany, [email protected]

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    xiv Contributors

    Murray K. Gingras Department of Earth and Atmospheric Sciences, University of

    Alberta, Edmonton, AB T6G 2E3, Canada, [email protected]

    Steven L. Goodbred, Jr. Department of Earth and Environmental Sciences,

    Vanderbilt University, Nashville, TN 37240, USA, [email protected]

    Stephen F. Greb Kentucky Geological Survey, University of Kentucky, Lexington,

    KY 40506, USA, [email protected]

    Christopher Hein Department of Earth Sciences, Boston University, Boston, MA

    02215, USA, [email protected]

    Zoe J. Hughes Department of Earth Sciences, Boston University, Boston, MA 01778,

    USA, [email protected]

    Aitor A. Ichaso Department of Geological Sciences and Geological Engineering,

    Queens University, Kingston, ON K7L 3N6, Canada, [email protected]

    Davood Jahani Department of Geology, Faculty of Basic Sciences, North Tehran

    Branch, Islamic Azad University, Tehran, Iran, [email protected]

    Erik P. Kvale Devon Energy Corporation, 20 North Broadway, Oklahoma City, OK

    73102, USA, [email protected]

    Yaghoob Lasemi Illinois State Geological Survey, Prairie Research Institute,

    University of Illinois at Urbana-Champaign, Champaign, IL 61820, USA, ylasemi@

    illinois.edu

    Zakaria Lasemi Illinois State Geological Survey, Prairie Reserarch Institute,

    University of Illinois at Urbana-Champaign, Champaign, IL 61820, USA,

    [email protected]

    James A. MacEachern Department of Earth Sciences, Simor Fraser Univeraity,

    8888 University Drive, Burnaby, BC V5A 1S6, Canada, [email protected]

    Duncan A. MacKay Department of Geological Sciences and Geological Engineering,

    Queens University, Kingston, ON K7L 3N6, Canada, [email protected]

    A.W. Martinius Statoil Research and Development, Arkitekt Ebbels vei 10, N-7005

    Trondheim, Norway, [email protected]

    Piret Plink-Bjorklund Department of Geology and Geologic Engineering, Colorado

    School of Mines, Golden, CO, USA, [email protected]

    Eugene C. Rankey Department of Geology, University of Kansas, 1475 Jayhawk

    Blvd., 120 Lindley Hall, Lawrence, KS 66045, USA, [email protected]

    Stacy Lynn Reeder Schlumberger-Doll Research, One Hampshire Street, Cambridge,

    MA 02139, USA, [email protected]

    Jean-Yves Reynaud Dpartement Histoire de la Terre UMR 7193 ISTeP, Musum

    National dHistoire Naturelle, Gologie, CP 48, 43, rue Buffon, F-75005 Paris,

    France, [email protected]

    Yoshiki Saito Geological Survey of Japan, AIST, Central 7, Higashi 1-1-1, Tsukuba

    305-8567, Japan, [email protected]

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    xvContributors

    Edward Simpson Department of Physical Sciences, Kutztown University, Kutztown,

    PA 19530, USA,[email protected]

    Ronald J. Steel Department of Geological Sciences, University of Texas Austin,

    Austin, TX 78712, USA, [email protected]

    Bernadette Tessier Morphodynamique Continentale et Ctire, University of Caen,

    UMR CNRS 6143, 24 Rue des Tilleuls, 14000 Caen, France, [email protected]

    Ping Wang Coastal Research Laboratory, Department of Geology, University of

    South Florida, Tampa, FL 33620, USA, [email protected]

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    2 E.P. Kvale

    lamina is directly and positively related to tidal current

    strength, which in turn is directly and positively related

    to the magnitude of the daily rise and fall of the tide

    (tidal range). Over periods of days, months, or years,

    changes in tidal current strengths associated with

    various lunar/solar cycles are mirrored by the change

    in thicknesses of the vertically stacked laminae.Modern and ancient tidal rhythmites have been found

    on every continent in the world except Antarctica. In

    modern environments, tidal rhythmites occur in depos-

    its associated with tide-dominated deltas, tidal embay-

    ments, and estuaries. Tidal rhythmites can be used for

    reconstructing ancient paleogeographies and paleocli-

    mates (e.g. this chapter, Hovikoski et al. 2005; Kvale

    et al. 1994), estimating paleotidal ranges (e.g. Archer

    1995; Archer and Johnson 1997), understanding chan-

    nel migration in the fluvio-estuaring transition (Choi

    2010) determining lunar-retreat rates through time (e.g.

    Williams 1989; Kvale et al. 1999), and most recently,

    have been used to infer the major tidal constituents

    associated with the tides that deposited them (e.g.

    Kvale 2006). In order to understand tidal rhythmites,

    however, one has to understand how tides are generated

    and what controls their genesis.

    The impact of diurnal, semidiurnal, and semimonthly

    (neap-spring) tidal cycles on sediment deposition has

    been well documented since the early 1980s (e.g. Visser

    1980; Boersma and Terwindt 1981; Allen 1981). For

    many geologists these became benchmark papers when

    they were published because they showed how deposi-

    tional packages within sedimentary successions can be

    linked to a tidal origin. However, it was the discovery

    of modern and ancient tidal rhythmites in the late 1980s

    and 1990s that showed that a hierarchy of tidal cycles,

    beyond simple semidaily, daily or fortnightly events,

    could be preserved in the rock record (e.g. Kvale et al.

    1989; Williams 1989; Dalrymple and Makino 1989;

    Archer et al. 1991; Kvale et al. 1994; Miller and

    Eriksson 1997). Tidal cycles associated with monthly,

    semiannual, annual (usually includes a significant sea-

    sonal climatic component), and even an approximately

    18-year cycle have been identified from ancient tidal

    rhythmites.

    Studies, however, showed that the understanding of

    one of the most basic of the tidal cycles, the neap-spring

    or fortnightly tidal cycle, by most geologists, and

    apparently many oceanographers, and astronomers as

    well, was over-simplified. Many college-level textbooks

    today continue to propagate a basic misunderstanding

    of the neap-spring cycles and the origin of oceanic

    tides in general (e.g. Duxbury et al. 2002).

    The intent of this chapter is neither to outline a

    history of the study of tides and tidal deposits nor to

    document the current state of knowledge regarding

    the history of the Earth-Moon system. These issues

    are treated in some detail in Klein (1998), Rosenberg(1997), Williams (2000), and Coughenour et al.

    (2009). Rather, it is to explain some basic tidal theory

    and show how a more complete knowledge of ancient

    tides can be extracted from the rock record. Most of

    the information contained within this chapter is dis-

    tilled from two summary papers: Kvale et al. (1999)

    and Kvale (2006).

    To truly understand tidal systems and, in particular,

    the genesis of tidal rhythmites it is useful to understand

    both an equilibrium tidal model and a dynamic tidal

    model. The former explains the driving forces behind

    the formation of tides and is commonly taught to

    geology, oceanography, and astronomy undergraduates,

    whereas the later, more accurately explains real-world

    tides and is more useful in interpreting the rock record.

    An understanding of both models is essential to anyone

    who studies tides and tidal deposits, and both will be

    discussed.

    1.2 Equilibrium Tidal Theory

    Most geologists understand tidal periodicities in the

    context of equilibrium tidal theory. Tides are generated

    by the gravitational forces of the Moon and, to a lesser

    degree, the Sun on the Earth. The Moon accounts for

    approximately 70% of the tide-raising force because of

    its proximity to the Earth. In an equilibrium world, the

    Earth is covered by an ocean of uniform depth that

    responds instantaneously to changes in tractive forces

    (MacMillan 1966). The equilibrium model can be used

    to explain five of the six tidal periodicities that have

    been commonly detected in rhythmite successions.

    These six cycles are illustrated in Figs. 1.11.6(previ-

    ously illustrated in Kvale et al. 1998). A seventh cycle

    known as the nodal cycle, an approximately 18 year-

    tidal cycle, and very well documented by Miller and

    Eriksson (1997) within the Pride Shale, a lower

    Carboniferous succession found in West Virginia, is

    not illustrated here.

    The figures each illustrate (from upper left to lower

    right): A diagram and explanation of the equilibrium

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    31 Tidal Constituents of Modern and Ancient Tidal Rhythmites: Criteria for Recognition and Analyses

    tidal theory of five of the six tidal periods; a bar chart

    of tidal height data (high tide elevations) from a modern,

    real-world setting that shows how the astronomical

    effects are reflected in cyclic changes in daily high

    tides; a core from an ancient tidal rhythmite succession

    showing how these cyclic tidal effects might be mani-

    fested in a laminated tidal rhythmite; and a bar chart of

    laminae thicknesses interpreted in the context of the

    modern tidal cycle.

    1.2.1 Semidiurnal (12.42 h)

    Within the equilibrium tidal model, the interaction of

    tidal forces from the Moon and Sun produce two oce-

    anic bulges on opposite sides of the Earth (Fig. 1.1).

    The rotation of a point on the Earth through these

    bulges once a day produces two tides (the semidiur-

    nal tide). Typically, these tides are not equal (termed

    diurnal inequality), as one tide is higher (dominant)

    than the other (subordinate) because the Moons

    orbital plane and the Earths equatorial plane are not

    parallel. The angular difference between the two

    planes is termed lunar declination.

    1.2.2 Synodic (29.53 Days)

    Daily high tides are higher when the Earth, Moon, and

    Sun are nearly aligned (full or new moon); this is

    referred to as syzygy (Fig. 1.2). Conversely, lower

    tides occur when the Sun and Moon are at right angles

    to the Earth (first or third quarter phase), also known as

    quadrature. Tides during full or new moon are

    referred to as spring tides: spring in this context

    refers to lively or energetic rather than implying a

    seasonal connotation. Tides at quarter phases are

    referred to as neap tides. The neap-spring tidal period

    Fig. 1.1 Semidiurnal equilibrium model. (a) Two oceanic tidalbulges are produced on opposite sides of the Earth by the gravita-

    tional forces of the Sun and the Moon. (b) Two tides are produced

    each day by the spin of the Earth through these bulges. The diur-

    nal inequality is produced when the tidal bulges are not centered

    above the Earths equator. Semidiurnal tides can be recognized in

    the rock record by the coupling of thick and thin lamina (c) and

    graphically in the thickness measurements of laminated sequences

    (d) as preserved in the tidal rhythmite succession from the

    Pennsylvanian Mansfield Formation (Hindostan whetstone beds)

    from Orange County, Indiana, USA (From Kvale and others

    (1998) and used by permission from SEPM)

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    4 E.P. Kvale

    in the equilibrium model is related to the changing

    phases of the Moon associated with the half-synodic

    month. The synodic month (new moon to new moon,

    or full moon to full moon) has a modern period of

    29.53 days and encompasses two neap-spring cycles.

    1.2.3 Tropical (Semidiurnal, 27.33 Days)

    The tidal force also depends on the declination of the

    Moon (Fig. 1.3). In this usage, declination refers to

    the tilt or angle of the Moons orbit relative to the

    Earths equatorial plane. The period of the variation in

    declination is called the tropical month the interval of

    time it takes the Moon to complete one full orbit from

    its maximum northern declination to its maximum

    southern declination and then return. The effect of the

    tropical month in an equilibrium semidiurnal tidal

    system is to cause the diurnal inequality of the tides.

    Ideally, diurnal inequality is greatest when the Moon is

    at its maximum declination. This inequality is reduced

    to zero when the Moon is over the equator, producing a

    crossover in the tidal data (Fig. 1.3). The current length

    of the tropical month is 27.32 days (2 days shorter than

    the synodic month see synodic discussion above).

    Because of this difference, equatorial passages of the

    Moon, called crossovers, have a shorter periodicity than

    the periodicity related to synodic neap-spring tides.

    1.2.4 Tropical (Diurnal, 27.32 Days)

    In modern, dominantly diurnal systems (primarily

    one tide per day), the tropical period described above

    Fig. 1.2 Synodic equilibrium model. (a) In an equilibriumtidal model, spring tides occur when the Earth, Moon, and Sun

    align during full or new moon (also known as syzygy).

    Equlibrium neap tides occur when the Moon-Earth alignment is

    90 from an Earth-Sun alignment (also known as quadrature).

    The synodic month (currently 29.53 days) is the time it takes forthe Moon to orbit the Earth when measured from a new Moon

    to the next new Moon. When neap-spring tides can be timed to

    phases of the Moon they are referred to as synodic neap-spring

    tides (Kvale 2006). (b) Graph of tidal heights of a portion of

    the 1991 predicted high tides for Kwajalein Atoll, Pacific

    (NOAA 1990) showing the effects of changing lunar phases.

    (c) Portion of a core from the Mansfield Formation (Hindostan

    whetstone beds), Indiana, USA with neap and spring tidal

    deposits labeled. (d) Measurements of laminae thicknessesfrom Hindostan whetstone beds with neap and spring tidal

    deposits labeled (From Kvale et al. (1998) and used by permis-

    sion from SEPM)

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    51 Tidal Constituents of Modern and Ancient Tidal Rhythmites: Criteria for Recognition and Analyses

    is responsible for generating neap-spring cycles. In

    contrast to the synodic system, tides in a tropical sys-

    tem behave as though the Suns gravitational effects

    are dampened, which is impossible to explain in an

    equilibrium tidal model (Fig. 1.4). In such cases, the

    dominant tidal force depends on the declination of

    the Moon relative to the Earths equator with the

    force being greatest when the Moon is most directly

    over the site in question. In these systems, the pre-

    dicted and ancient tide data reveal that equatorial

    passages of the Moon (crossovers) occur in phase

    with the generation of neap-spring tides, in contrast

    to the variable relationship exhibited by tropical

    (semidiurnal) tides.

    1.2.5 Anomalistic (27.55 Days)

    Another tidal effect arises from the changing distance of

    the Moon relative to the Earth during the lunar orbit

    (Fig. 1.5). Because the lunar orbit forms an ellipse, with

    the Earth slightly offset from the center, the Moon alter-

    nates between perigee (closest approach to the Earth) and

    apogee (the farthest distance from the Earth). During the

    lunar synodic month there will be two spring tides (see

    synodic periods described above). These spring tides,

    however, will be of unequal magnitude producing alter-

    nating high-spring and low-spring tides, which corre-

    spond to spring tides during or near perigee (high spring)

    and spring tides during or near apogee (low spring).

    Fig. 1.3 Tropical, semidiurnal equilibrium model. (a) Model of theMoon in orbit around the Earth. The lunar declination is exaggerated

    from its modern range of 1828. The tropical month (currently

    27.32 days) is the time it takes for the Moon to move from its

    maximum northern declination to its southernmost declination and

    back to its northernmost declination in a single orbit. (b) Graph

    of tidal heights of a portion of the same modern tidal record shown

    in Fig. 1.2b illustrating diurnal inequality of semidiurnal tides.

    Note diurnal inequality goes to zero when the Moon passes

    directly over the Earths equator. (c) Image of core shown in

    Fig. 1.2cshowing approximate position (labeled C) when Moon

    was above the Earths equator during deposition. Note the approx-

    imate equal thicknesses of the lamina on either side of the arrow.

    (d)Bar chartshown in Fig. 1.2dwith arrows denoting passages

    of the Moon above the Earths equator during deposition (From

    Kvale et al. (1998) and used by permission from SEPM)

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    6 E.P. Kvale

    The semimonthly inequality of the spring tides disappears

    when the Moon lies along the minor axis of the lunar

    orbit and the difference in lunar distance is minimized

    during subsequent spring tides. The time it takes for the

    Moon to move from perigee to perigee is called the

    anomalistic month, which is at present 27.55 days.

    1.2.6 Semiannual (182.6 Days)

    The synodic, tropical, and anomalistic periods have

    slightly different values. Because of this, these periods

    will interact constructively twice each year causing tidal

    forces at these times to reach a maximum (as shown by

    the dashed line in Fig. 1.6). In the equilibrium tidal

    model, the date of this tidal maximum is a function of

    latitude that is related to the declinational effects of the

    Moon and Sun. An annual inequality has been docu-

    mented in several ancient tidal rhythmite successions

    (Kvale et al. 1994). This inequality is interpreted to be

    climatic (non-tidal) in origin.

    1.3 Dynamic Tidal Theory

    As noted in the introduction, the equilibrium tidal

    model explains the driving forces that cause tides but

    does not explain real-world tides. For instance, the

    Fig. 1.4 Tropical diurnal model. (a) Model of the Moon in itsorbit around the Earth (see Fig. 1.3a). (b) Graph showing the

    1994 predicted relative high tides (mixed, predominantly diur-nal) for the Barito River estuary in Borneo (NOAA 1993). Note

    the passages of the Moon above the Earths equator perfectly

    track the neap tides and spring tides to the maximum declinations

    of the Moon in its orbit around the Earth, a pattern not predicted

    by equilibrium tidal theory. Such neap-spring tidal cycles are

    termed tropical neap-spring tides (Kvale 2006). (c) Photograph

    of a portion of a core from the Pennsylvanian Brazil Formation,

    Daviess County, Indiana, USA. Arrowsindicate lamina depos-

    ited with the Moon was above the Earths equator. (d)Bar chartof lamina thicknesses measured from core obtained from the

    Brazil Formation. This unit also is mixed, predominantly diurnal.

    Note the diurnal inequality of the semidiurnal component goes to

    zero only in the neap tide deposits. This corresponds to the Moon

    above the Earths equator during deposition (From Kvale and

    others (1998) and used by permission from SEPM)

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    71 Tidal Constituents of Modern and Ancient Tidal Rhythmites: Criteria for Recognition and Analyses

    world does not spin through two tidal bulges. Instead,

    oceanic tides rotate as waves around fixed (amphidro-

    mic) points within individual ocean basins (Fig. 1.7).

    Equilibrium tidal theory indicates that diurnal tides

    should exist only at very high latitudinal positions,

    which is not the case. For example, the Gulf of Mexico

    and large tracts in the Indian and western Pacific oceans

    are dominated by diurnal tides. Tides like those found

    in Immingham, England, where the semidiurnal tides

    have minimal diurnal inequality, cannot be explained

    by equilibrium tidal theory, which requires such tides

    to exist only in equatorial positions. Finally, equilib-

    rium tidal theory does not explain neap-spring tidal

    cycles which are synchronous with the 27.32 tropical

    monthly period such as illustrated in Fig. 1.4.

    The difficulties in understanding and explaining

    real-world tides can be addressed by a dynamic tidal

    model. This model is built around the concept of a

    harmonic analysis of the components that compose

    real-world tides. For instance, the Moon and Sun each

    generate their own tide within the Earths oceans. Since

    the orbits of the Earth around the Sun and the Moon

    around the Earth are not perfectly circular, the ampli-

    tude of the tides generated by each of these bodies, in

    part, fluctuates depending on the Earths proximity

    to the Sun and, much more importantly, the Moons

    distance from the Earth. Periodically each of these

    tides will constructively or destructively interact with

    each other. The tides associated with changes in Moon-

    Earth distance or Earth-Sun distance can be considered

    to be a constituent of the overall tide, which can affect

    any coastline.

    To model these tidal constituents (also known as

    tidal species) oceanographers conceptualize each

    Fig. 1.5 Anomalistic equilibrium model. (a) Polar view of theMoon in orbit around the Earth. Note that lunar orbit is not

    perfectly circular but somewhat elliptical (greatly exaggerated

    in the diagram) and that the Earth is not position in the direct

    center of the orbit path. The time it takes for the Moon to go

    from perigee (closest approach) to apogee (furthest from the

    Earth) and return is called the anomalistic month, which is27.55 days long at present. (b) Graph showing the 1992 pre-

    dicted high tides for Saint John, New Brunswick, Canada

    (NOAA 1991) showing the effects of the anomalistic month on

    the Saint John tides. Note the semimonthly inequality goes to

    zero when the Moon and Sun are aligned with the Moons

    minor orbital axis (termed phase flip). (c) Photograph of a

    core from the Mississippian Tar Springs Formation, Indiana,

    USA showing the effects of the anomalistic month on neap-

    spring tidal deposition. (d) Graph illustrating thicknesses as

    measured between neap-to-neap tide deposits from the TarSprings Formation core, a portion of which is shown in

    Fig. 1.5c. Note the position of the phase flip (From Kvale

    et al. (1998) and used by permission from SEPM)

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    8 E.P. Kvale

    constituent as a phantom satellite that has its own

    mass (that of the Moon, Sun, or a combination of the

    two). Each phantom satellite has a motion within a

    plane or is fixed relative to the stars and each generates

    its own tide with a unique period, response time, and

    amplitude (Pugh 1987) (Table 1.1). For instance S2

    represents the twice-daily tide generated at a fixed

    point on the Earth by a satellite that has the mass of

    the Sun in a perfectly circular orbit around the Earths

    equator. O1 represents the daily tide generated at a

    fixed point on the Earth by a satellite with a mass of

    the Moon and a motion above the Earths equator. For

    each of the tidal constituents, the subscript indicates

    if the tide is diurnal (1) or semidiurnal (

    2).

    The relative intensity for each of these tidal constitu-

    ents along any oceanic coastline in the world can be

    determined by a harmonic decoupling of an extended

    hourly tidal record. These measurements typically are

    recorded in most major harbors and other tidal stations

    around the world. More than 100 tidal constituents have

    been identified from a harmonic extraction of Earths

    tides, however, seven of these (Table 1.1) account for

    more than 80% of any real-world tide (Defant 1961).

    The resonate amplification or destruction of these tidal

    constituents determines the resulting tide for a specific

    area within the Earths oceans (Fig. 1.8).

    As noted above, each of these tidal constituents

    corresponds to a unique tidal wave. These waves do

    not travel around the world as predicted by equilibrium

    tidal theory, but rather rotate around a point (referred

    to as an amphidromic point) within a region of the

    ocean at a speed determined by their constituents

    orbital periodicity or the periodicity of the Earths spin

    (Fig. 1.7). The location of these points is determined

    by basin geometries and the Coriolis force.

    Ideally, amphidromic circulation should be counter-

    clockwise in the Northern Hemisphere and clockwise

    in the Southern Hemisphere and never on the equator

    Fig. 1.6 Semiannual equilibrium model. (a) View of the con-figuration of the Earth, Moon, and Sun representing the maxi-

    mum spring tides formed when the Moon is at perigee, maximum

    northern declination and new. Such spring tides occur every

    182.6 days. (b) 1992 predicted high tides from Saint John, New

    Brunswick, Canada (NOAA 1991) showing the effects of the

    semiannual convergence of maximum spring tides. (c) Photograph

    of a core from the Pennsylvanian Lead Creek Limestone, Indiana,

    USA. In this core the neap-spring cycles thicken and thin in a

    semiannual pattern. (d) Graph showing the thicknesses of

    individual lamina from the Brazil Formation, Indiana. These

    thicknesses are also organized into semiannual tidal cycles. Each

    number records an individual neap-spring cycle (From Kvale

    et al. (1998) and used by permission from SEPM)

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    91 Tidal Constituents of Modern and Ancient Tidal Rhythmites: Criteria for Recognition and Analyses

    but, as shown above, real-world tides dont always

    follow convention and exceptions are known (Open

    University Course Team 1999).

    The major tidal cycles discussed under the equilib-

    rium model can be understood in the context of the

    dynamic model and tidal constituents. Specifically, the

    synodic neap-spring cycle is generated through the

    interaction of the S2and M

    2constituents. In the modern

    world, these two tides come into phase and amplify the

    resulting tide every 14.77 days. The result is a syn-

    odic spring tide. Conversely, every 13.66 days K1and

    O1 converge and generate a tropical spring tide.Whether a spring tide along a specific coastline is

    dominated by the synodic spring tide or the tropical

    spring tide is determined by the basin geometry. For

    instance, the Gulf of Mexico is dominated by the K1

    and O1tides, therefore neap-spring tides cycle with the

    tropical month (Fig. 1.9). The east coast of the USA,

    however, is dominated by S2and M

    2tides resulting in

    neap-spring tides that cycle with the synodic month

    (Fig. 1.9). The semimonthly inequality of spring tides

    occurs because of the convergence of M2and N

    2every

    27.55 days. A diurnal inequality is driven by the inter-

    action of O1and M

    2(in phase once a day) and is noted

    in coastal tides when these constituents are of suffi-

    cient amplitude.

    One can look at the progressive change in relative

    intensity of particular tidal constituent along a coast

    and see how that affects the resulting tides. For exam-

    ple, Figs. 1.10and 1.11shows the amplitudes for the

    seven dominant tidal constituents for the Gulf of

    Carpentaria, Australia and the tidal patterns that result

    from changes in the relative amplitudes of the various

    constituents (from Kvale 2006). At the mouth of the

    gulf at Booby Island, the tides are dominated by M2,

    K1 and O

    1. Given the dominance of O

    1 and K

    1, the

    neap-spring cycle occurs every 27.32 days and corre-

    sponds to the tropical monthly period. However, unlike

    many regions whose neap-spring cycles are tropically

    driven, there is a relatively strong M2tide (but relatively

    weak S2 tide) at the mouth of the gulf. The resultant

    Fig. 1.7 Diagram showing the amphidromic circulation for theM

    2tide in the North Sea. Co-tidal lines indicate times of high

    water. And co-range lines indicate lines of equal tidal range.

    Figure is modified from Dalrymple (1992) which was based on

    a map first drawn by J. Proudman and A. T. Doodson (From

    information found in Cartwright 1999) (From Kvale (2006) and

    used by permission from Marine Geology)

    Table 1.1 List of the seven most common tidal constituents, their rotational speed (number of degrees a tidal wave generated bythe constituent can travel around its amphidromic point in 1 h), description, and period in solar hours (Defant 1961)

    Tidal constituent Speed (degrees/hour) Origin Period in solar hours

    M2

    28.9841 Principal lunar 12.42

    S2

    30 Principal solar 12

    N2

    28.4397 Larger elliptical lunar 12.66

    K2

    30.0821 Combined declinational lunar

    and declinational solar

    11.97

    K1

    15.0411 Combined declinational lunar

    and declinational solar

    23.93

    O1

    13.943 Principal lunar 25.82

    P1 14.9589 Principal solar 24.07

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    10 E.P. Kvale

    tide at Booby Island exhibits a tropically driven

    neap-spring cyclicity comparable to the tide depicted

    in Fig. 1.4except that it also exhibits a strong semidi-

    urnal component that is driven by M2. Progressing fur-

    ther south into the Gulf of Carpentaria, the strengths of

    K1and O

    1increase relative to M

    2creating a tide that is

    dominantly diurnal.

    1.4 Ancient Tides

    Some tidal rhythmites in the rock record preserve long

    (several months worth), relatively complete succes-

    sions of daily or semidaily tidal deposition. Particularly

    complete records can be interpreted in the context of

    the dynamic tidal model and several examples are

    noted below.

    1.4.1 Hindostan Whetstone Beds

    (Pennsylvanian, Indiana)

    Figures 1.2and 1.3show both a segment of core and a

    bar chart of the laminae thicknesses from the Hindostan

    Whetstone beds found in Orange County, Indiana

    (Kvale et al. 1989). Neap-spring cycles in this chart

    occur more frequently than crossovers indicating that

    these tides were synodically driven and hence related

    to the dominance of the M2and S

    2over the O

    1and K

    1

    constituents. Some caution is needed, however, in

    interpreting crossover patterns because the absence of

    a single half-day event could cause an apparent cross-

    over. Ways to infer completeness of a tidal pattern are

    discussed by Kvale et al. (1999). Suffice it to state that

    with suitably long tidal rhythmite records, such as

    presented here, it is possible to interpret crossover

    patterns with some confidence.

    This example clearly shows a diurnal inequality,

    and, as such, O1must be significant. There appears to

    be a lack of a pronounced semimonthly inequality

    (anomalistic cycle) suggesting that N2 was relatively

    weak. Therefore, tides that deposited the Hindostan

    Whetstone beds were dominated by the constituents

    M2, S

    2, and O

    1followed by K

    1and N

    2.

    1.4.2 Brazil Formation (Pennsylvanian,Indiana)

    Figure 1.4show a segment of core and a bar chart of

    laminae thicknesses from the Brazil Formation of

    Daviess County, Indiana (Kvale and Archer 1990;

    Kvale and Mastalerz 1998). The neap-spring cycles in

    this example occur at the same frequency as the cross-

    overs indicating that these tides were driven by the

    tropical period and hence reflect a dominance of O1

    and K1 over S

    2 and M

    2. A weak semidiurnal signal

    occurs during the neap tides and indicates that M2had

    some amplitude and importance in the resulting tide.

    The Brazil Formation rhythmites, like the whetstone

    beds discussed above, lack a prominent semimonthly

    inequality suggesting a weak N2 tidal constituent. It

    can be inferred from this data base that the Brazil

    Fig. 1.8 Resulting tide predicted from the stacking of 9 differenttidal constituents. Horizontal units are in hours (Modified from

    MacMillan, 1966 in Kvale, (2006) and used by permission from

    Marine Geology)

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    111 Tidal Constituents of Modern and Ancient Tidal Rhythmites: Criteria for Recognition and Analyses

    Fig. 1.9 Graphs showing predicted high-data for two tidalreferences stations from the east coast and Gulf coast USA. The

    Port Manatee example is typical of the tides in the Gulf coast

    and the Hunniwell graph typifies east coast tides. Both tidal

    records cover the same interval of time from January through

    early May, 2005 (National Oceanographic and Atmospheric

    Administration Web site 2004). Note that the equatorial pas-

    sages of the Moon are fixed with the neap tides in the Gulf

    coast station but move through the graph in the east coast exam-

    ple. As such, Gulf coast neap-spring tides are driven by the

    tropical month but the east coast neap-spring tides are controlled

    by the phase changes of the Moon associated with the synodic

    month (From Kvale (2006) and used by permission from Marine

    Geology)

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    12 E.P. Kvale

    Fig. 1.10 Graphs andlocation map for predicted

    high-tide data from three tidal

    reference station in the Gulf

    of Carpentaria, Australia.

    The time interval for each

    graph spans January through

    early June, 2004 (AustralianNational Tidal Centre, Bureau

    of Meteorology Web site,

    2004) (From Kvale (2006)

    and used by permission from

    Marine Geology)

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    131 Tidal Constituents of Modern and Ancient Tidal Rhythmites: Criteria for Recognition and Analyses

    Formation tides were dominated by O1, K

    1, followed

    by M2with very weak contributions from S

    2and N

    2.

    1.4.3 Abbott Sandstone (TradewaterFormation, Pennsylvanian, Illinois)

    Figure 1.12shows an outcrop and bundle thicknesses from

    some flaggy, large-scale tidal bundles along Interstate 57

    in Johnson County, Illinois (Kvale and Archer 1991). A

    histogram of bundle thicknesses indicates a strong semidi-

    urnal signal throughout the record. While not as clean a

    tidal record as the two previous examples, the Abbott

    sandstone example appears to exhibit minimal diurnal

    inequality during the neap tides. When the diurnal inequal-

    ity tracks neap tides, it indicates that neap-spring cyclicity

    is driven by the tropical period (e.g. Fig. 1.4). As such, the

    Abbott Sandstone tidal record resembles that of Booby

    Island, Australia (Fig. 1.10), in which M2, O

    1and K

    1dom-

    inate the resultant tide over S2. There is a suggestion of a

    semimonthly inequality to the Abbott sandstone record

    indicating that N2was stronger than S

    2 and sufficiently

    strong to influence the tidal record.

    These examples illustrate that tidal constituents

    can be extracted from the rock record in well-preserved

    tidal rhythmites. While it is not always possible to

    draw conclusions regarding so many tidal constitu-

    ents, deposits can generally be determined to be either

    diurnal or semidiurnal in nature based on the absence

    or occurrence of alternating thick-thin laminae. Most,

    but not all, semidiurnal tidal deposits can be related

    to the synodic period and the convergence of M2and

    S2constituents. Exceptions of semidiurnal, tropically

    driven neap-spring tides or tidal deposits, such as

    Booby Island and the Abbott Sandstone, are known

    and can be discerned if the tidal record is long and

    clean enough. All diurnal deposits should have been

    deposited in tropically driven neap-spring cycles.

    Semidiurnal depositional systems that lack strong K1

    or O1constituents (like Effingham, England), and in

    which tidal sediments were deposited only on high

    intertidal zones might mimic a diurnal tidal deposit

    (Archer and Johnson 1997). In such a case, additional

    outcrop work might result in the discovery of lower

    intertidal or subtidal facies that would resolve the

    issue.

    Fig. 1.11 Line graph showing the changes in tidal amplitudefor the seven most dominant tidal constituents for several tidal

    reference stations located along the eastern side of the Gulf of

    Carpentaria (locations noted in Fig. 1.10. Constituent data was

    extracted using the Seafarer Tides software package by the

    Australian National Tidal Centre, Bureau of Meteorology and

    provided to Kvale (2006) (From Kvale (2006) and used by per-

    mission from Marine Geology)

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    14 E.P. Kvale

    1.5 Summary and Implications

    The equilibrium tidal model is very useful for explain-

    ing the gravitational forces that generate tides on the

    Earth. However, it is an over-simplification and does not

    explain the tides in most of the oceans of the world. To

    explain real-world tides requires a basic understanding

    of the dynamic tidal model. The dynamic tidal model

    has been used to estimate changes in the Earth-Moon

    distance through time (Williams 1989; Kvale et al.

    1999) and has even been suggested as a way to better

    understand the impact that tides have on biological

    systems (Kvale 2006). It has also been used to model

    tidal basin dynamics for determining the importance of

    tidal facies within a basin or region (e.g. Ericksen and

    Slingerland 1990; Wells et al. 2007). In the Abbott

    example, an interpretation of neap-spring cyclicity could

    be done with both the equilibrium and dynamic model,

    but interpretation of the relative importance of the M2,

    Fig. 1.12 Tradewater Formation, (a) Photo of the Abbottsandstone outcrop. This is part of a much more extensive

    dune mesoform. Examples of dominant (D) and subordinate

    (S) semidiurnal foresets are labeled. Rock hammer for

    scale (lower part of photo) (b) Bar chart showing foreset

    (depositional event) thickness variability with spring tides (S),

    neap tides (N) and lunar crossover (arrows) events labeled.

    Notice the semimonthly inequality of the spring tides related

    to perigee and apogee effects. Also note that the lunar

    passages of the equator (arrows) track the neap tide deposits

    fairly closely suggesting that the neap-spring cycles are in

    phase with the tropical month

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    151 Tidal Constituents of Modern and Ancient Tidal Rhythmites: Criteria for Recognition and Analyses

    S2, O

    1, K

    1, and N

    2constituents using the dynamic model

    allows much more specific comparisons to be made to

    real-world analogues (in this case Booby Island tides)

    than would otherwise be possible. In fact, utilizing this

    approach within the Illinois Basin one can interpret the

    dominance of diurnal (O1and K

    1) tides versus semidiurnal

    (M2and S

    2) tides for various tidal rhythmite packages

    that span the Mississippian-Pennsylvanian systems

    (Fig. 1.13). As Fig. 1.13shows, tidal rhythmites older

    than the upper Morrowan Blue Creek Coal appear to

    have been deposited within synodically driven systems

    dominated by M2 and S

    2. Younger tidal rhythmites

    appear to have been deposited within tropically driven

    systems. This change from synodically driven to tropically

    driven tidal systems may reflect the closure of the

    Iapetus Ocean during the early Pennsylvanian and a

    Fig. 1.13 Stratigraphic chart for the Indiana portion of the IllinoisBasin showing stratigraphic intervals where good tidal rhythmite

    records have been identified by the author. The solid grey line

    marks the boundary below which tidal rhythmites seem to be con-

    trolled primarily by the synodic monthly cycle and above which

    the tidal rhythmites appear to reflect the tropical monthly cycle

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    16 E.P. Kvale

    major change in tidal dynamics within the midcontinent

    Carboniferous sea of North America.

    While teaching and understanding the dynamic

    tidal system represents a bit of a paradigm shift to most

    geologists, it creates possible research venues not

    accessible through an understanding of equilibrium

    tidal theory alone.

    References

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    19R.A. Davis, Jr. and R.W. Dalrymple (eds.), Principles of Tidal Sedimentology,

    DOI 10.1007/978-94-007-0123-6_2, Springer Science+Business Media B.V. 2012

    2Principles of Sediment TransportApplicable in Tidal EnvironmentsPing Wang

    Notations and Conventional Units

    a: a reference level (typically defined at the top level

    of the bedload layer) for suspended sediment con-

    centration. (m)

    c: suspended sediment concentration (dimension-

    less for volume concentration, kg/m3for mass

    concentration)

    ca: reference concentration (dimensionless for vol-

    ume concentration, kg/m3for mass concentration)

    c(z): suspended sediment concentration profile

    (dimensionless for volume concentration, kg/

    m3for mass concentration)P. Wang (*)

    Coastal Research Laboratory, Department of Geology,

    University of South Florida, Tampa, FL 33620, USA

    e-mail: [email protected]

    Abstract

    Physical processes of sediment transport in tidal environments are extremely

    complicated and are influenced by numerous hydrodynamic and sedimentological

    factors over a wide range of temporal and spatial scales. Both tide and wave forcingplay significant roles in the entrainment and transport of both cohesive and

    non-cohesive particles. Present understanding of sediment transport is largely

    empirical and based heavily on field and laboratory measurements. Sediment

    transport is composed of three phases: (1) initiation of motion (erosion), (2) trans-

    port, and (3) deposition. In tidal environments, the coarser non-cohesive sediments

    are typically transported as bedload, forming various types of bedforms. The finer

    cohesive sediments tend to be transported as suspended load, with their deposition

    occurring mostly during slack tides under calm conditions. Rate of sediment

    transport is generally proportional to flow velocity to the 3rd to 5th power. This

    non-linear relationship leads to a net transport in the direction of the faster velocity

    in tidal environments with a time-velocity asymmetry. Due to the slow settling

    velocity of fine cohesive sediment and a difference between the critical shear stress

    for erosion and deposition, scour and settling lags exist in many tidal environ-

    ments resulting in a landward-fining trend of sediment grain size. The periodic

    reversing of tidal flow directions results in characteristic bi-directional sedimen-

    tary structures. The relatively tranquil slack tides allow the deposition of muddy

    layers in between the sandy layers deposited during flood and ebb tides, forming

    the commonly observed lenticular, wavy, and flaser bedding.

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    20 P. Wang

    c : depth averaged concentration (dimensionless

    for volume concentration, kg/m3 for mass

    concentration)

    D: sediment grain size (m)

    D*: dimensionless sediment grain size (dimension-

    less)

    Dw: wave-energy dissipation due to breaking(kg/s3)

    dm: mean sediment grain size (m)

    d50

    : 50th percentile sediment grain size (m)

    E: wave energy per unit water volume (kg/s2)

    fc: bottom friction coefficient (dimensionless)

    H: wave height (m)

    h: water depth (m)

    kd: empirical coefficients used in suspended sediment

    concentration profile modeling (dimensionless)

    kx: dispersion coefficient in x direction (dimen-

    sionless)ky: dispersion coefficient in y direction (dimen-

    sionless)

    L: wave length (m)

    Ls: turbulent mixing length (m)

    Qb: volumetric bed-load transport rate (m3/m/s)

    qs: volume rate of suspended sediment transport

    (m3/m/s)

    S = source and sink terms

    s: sediment specific density =s/

    w (dimension-

    less)

    T: wave period (s)

    U: near bottom wave orbital velocity (m/s)

    u(z): current velocity with respect to depthz(m/s)

    u : depth-averaged current velocity (m/s)

    u*: current related bed-shear velocity (m/s)

    u*_c

    : critical bed shear velocity (m/s)

    u*_crs

    : critical shear velocity for sediment suspension

    (m/s)

    cru : depth-averaged critical velocity (m/s)

    v : depth average velocity inydirection (m/s)

    ws: settling velocity (m/s)

    ws_s

    : settling velocity of single suspended particle

    in clear water used in the calculation of the

    settling velocity of flocs (m/s)

    z: vertical coordinate representing water depth (m)

    zo: vertical level with zero velocity, also often

    referred to as bed roughness (m)

    1: empirical coefficients used in suspended sedi-

    ment concentration profile modeling (dimen-

    sionless)

    a2: empirical coefficients used in suspended sedi-

    ment concentration profile modeling (dimen-

    sionless)

    b: empirical coefficients used in suspended sedi-

    ment concentration profile modeling (dimen-

    sionless)

    s: sediment mixing coefficientq: Shields parameter (dimensionless)

    qc: critical Shields parameter (dimensionless)

    qcrs

    : critical Shields parameter for sediment

    suspension (dimensionless)

    : Von Karmans constant, typically taken as 0.4

    (dimensionless)

    : an efficiency factor to incorporate the influ-

    ence of bedforms on bedload transport used in

    the Meyer-Peter and Mueller (1948) bedload

    transport formula (dimensionless)

    n: kinematic viscosity (m2/s)

    s: sediment density (kg/m3)

    rw: density of water (seawater in the case of tidal

    environment) (kg/m3)

    tb: bed shear stress (N/m2)

    tc: critical bed shear stress (N/m2)

    flocf : flocculation factor (dimensionless)

    hs

    f : hindered settling factor (dimensionless)

    2.1 Introduction

    Coastal sedimentology and morphodynamics are con-

    trolled by a variety of interactive factors, including forces

    from ocean tides and waves, trends and rates of sea-

    level changes, sediment supply, climatic and oceano-

    graphic settings, and antecedent geology. Depending

    on the relative dominance of wave and tide forcing,

    coastal environments can be classified as tide-dominated

    and wave-dominated (Davis and Hayes 1984). This

    chapter focuses on general physical processes of sedi-

    ment transport that are applicable to the tide-dominated

    environments. In this chapter, tidal environments are

    defined generally as shallow marine environments that

    are significantly influenced by tides.

    The rise and fall of tides provide the main mecha-

    nism for sediment transport and morphology changes

    in tidal environments. In addition to generating tidal

    current which constitutes the dominant forcing in tidal

    environments, this regulated water-level fluctuation

    can also modulate wave action. For example, higher

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    212 Principles of Sediment Transport Applicable in Tidal Environments

    waves were often measured at a fixed location on a

    tidal flat during higher tides due to less friction related

    wave dissipation (Lee et al. 2004; Talke and Stacey

    2008). Sediment transport by wave forcing can be

    significant locally, as well as during storm conditions.

    Bottom shear stress, and therefore initiation of sedi-

    ment motion and transport, is also strongly influencedby water depth, which varies substantially in tidal

    environments. When the tidal water-level fluctuations

    are confined by channels, e.g., tidal inlets and creeks,

    strong tidal-driven flows can be generated. As com-

    pared to other types of channelized flow, tidal flow

    reverses direction periodically with a slack water period

    in between, which may create unique bi-directional

    sedimentary structures. In the case of tidal inlets

    between barrier islands, large flood and ebb tidal deltas

    can be deposited through the interaction of tide and

    wave forcing. The cyclical rising, slacking, and fallingtide and the associated flow variation leave signature

    sedimentary records through geological history, pro-

    viding valuable information for understanding earth

    history (e.g. Kvale et al. 1989).

    Sediment grain size in tidal environment typically

    ranges from non-cohesive medium sand to cohesive

    clay. Compositionally, tidal sediments can be silici-

    clastic, carbonate, and organic materials. A variety of

    sedimentary structures, ranging from millimeter-scale

    sand-mud laminations on tidal flats to subaqueous

    dunes of tens of meters in tidal channels, exists in

    tidal environments, indicating a wide range of sedi-

    ment transport and deposition processes. Transport

    and deposition of mixed cohesive and non-cohesive

    sediments are poorly understood and provide cutting

    edge research topics (Van Rijn 2007a, b, c)

    Given the wide range of both cohesive and non-

    cohesive sediments, and the energetic and highly vari-

    able hydrodynamic processes driven by both tides and

    waves, sediment transport processes in tidal environ-

    ments are extremely complicated. This chapter aims

    at providing a basic review of the principals of sedi-

    ment transport applicable in tidal environments.

    Various transport formulas and their general applica-

    tions in tidal environments are discussed. It is worth

    emphasizing that methods of computing the rates of

    sediment transport are largely empirical, based

    heavily on field and laboratory experiments.

    Calibration and verification based on site-specific

    data are essential to accurate applications of the formulas.

    The transport principles and formulae can also be

    applied qualitatively to interpret the sedimentary

    processes observed in the field, and to design field

    experiments. More detailed and further in-depth

    mechanics of sediment transport can be found in

    several dedicated texts, e.g., Mehta (1986b), Fredsoe

    and Deigaard (1992), Nielsen (1992),Van Rijn (1993),

    Pye (1994), Allen (1997), and Soulsby (1997).

    2.2 Principles of Sediment Transport

    Transport of sediment in coastal environments results

    from the interaction between moving fluid (seawater in

    this case) and sediment. Present knowledge on sedi-

    ment transport processes is largely empirical, based on

    numerous field and laboratory experiments. Insightful

    parameterization is crucial in describing the compli-cated fluid-sediment interaction. In the following

    section, key parameters describing fluid motion, sedi-

    ment, and fluid-sediment interaction are discussed,

    followed by the presentation of the commonly-used

    methods for the calculation of non-cohesive and

    cohesive sediment transport, respectively.

    2.2.1 Fundamental Parameters

    Fluid motion over a sediment bed exerts a horizontal

    drag force and a vertical lift force. Generally, when

    these forces overcome the gravity of a sediment grain,

    transport is initiated. A theoretical analysis of the ini-

    tiation of motion of an individual grain typically starts

    with a force balancing between the drag-lift forces and

    the gravitational force on the grain. The sediment grain

    is put in motion if the moments of the fluid drag (FD

    ) and

    lift (FL) forces exceed the moments of the submerged

    gravitational force (FG) on the grain (Fig. 2.1). However,

    due to our limited understanding of the very compli-

    cated fluid-sediment interaction, sediment transport in

    the natural environments cannot be quantified from the

    force analysis of each grain. Instead, it is quantified

    empirically through insightful parameterization of sediment-

    fluid interaction, as discussed in the following.

    When viscous fluid, e.g., seawater, flows over a sur-

    face, a shear stress is generated by the fluid flow. This

    shear stress is responsible for entraining and transport-

    ing sediment. On the other hand, the friction at the

    fluid-sediment interface exerts a drag on the fluid flow,

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    22 P. Wang

    yielding the commonly observed logarithmic velocityprofile over depth, i.e., the law of the wall:

    *( ) ln

    o

    u zu z

    zk

    (2.1)

    Where u(z) = current velocity with respect to depth,

    z= vertical coordinate representing water depth,

    u*= current related bed-shear velocity, = Von Karmans

    constant, typically taken as 0.4, and zo= vertical level

    with zero velocity, also often referred to as bed rough-

    ness. A list of notation and conventional units are pro-

    vided at the beginning of this chapter. Figure 2.2

    illustrates an example of a logarithmic profile. The

    dynamics of the bottom boundary layer where the cur-

    rent velocity decreases rapidly with respect of depth is

    crucial to sediment entrainment and transport. For plane

    bed, the bed roughness (Fig. 2.2) is a function of sedi-

    ment grain size. When bedforms exist, the bed roughness

    is related to the geometry of the bedform. The bed shear

    velocity is directly related to bed shear stress (tb) as:

    2

    *b wut r (2.2)

    where rw= density of water (seawater in the case of tidal

    environments). The bed shear velocity and bed shear

    stress are two of the key parameters describing the fluid-

    sediment interaction and are commonly used in comput-

    ing sediment transport. Determining bed shear velocity

    and bed shear stress can be difficult and often comprises

    an essential part of a sediment transport study. By mea-

    suring a velocity profile through the water column,

    Eq. 2.1can be used to determine bed shear velocity and

    bed shear stress, as well as the bottom roughness.

    Another commonly used approach to determine the bot-

    tom shear stress, especially for depth-averaged models,

    is to relate bottom stress to velocity squared as:

    21

    2b w c

    f ut r (2.3)

    Fig. 2.1 Schematic forcebalancing of individual

    grains on a horizontal bed

    Fig. 2.2 An example of a logarithmic current profile, showing thebed roughness (z

    o) and the schematic bottom boundary layer

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    232 Principles of Sediment Transport Applicable in Tidal Environments

    where fc is a bottom friction coefficient, determined

    experimentally, and u = depth-averaged current velocity.

    Equation 2.3describes the so-called quadratic friction

    law, i.e., the friction exerted by a fluid flow is pro-

    portional to its velocity squared. Equations 2.12.3

    suggest that the faster the flow velocity and the rougher

    the bed, the greater the shear stress, and therefore thegreater potential of sediment transport.

    Although wave forcing is not the dominant factor in

    determining the overall morphology and sedimentation

    pattern in tidal environments, it is important in local

    sediment entrainment and transport. For example,

    numerous studies have shown that wave forcing can

    have significant influence on the sedimentology and

    morphodynamics of tidal flats (Christie et al. 1999;

    Dyer 1998; Dyer et al. 2000; Li et al. 2000; Talke and

    Stacey 2003, 2008; Lee et al. 2004). Wave motion can

    be visualized as a circular motion of an imaginarywater particle. This wave orbital velocity, especially

    near the bottom, can induce considerable shear stress

    to entrain and transport sediment. Based on linear

    wave theory, the maximum value of near bottom orbital

    velocity (U) is:

    2sinh

    HU

    hT

    L

    d

    p

    p

    (2.4)

    where h= water depth, L= wave length, T= wave

    period, andH= wave height.

    In a more simplified larger scale approach, wave-

    induced sediment transport is often evaluated based on

    the amount of energy that is carried by the wave.

    Higher wave energy typically results in more active

    sediment transport. Wave energy per unit water

    volume (E) is determined as:

    21

    8 w

    E gHr (2.5)

    Equation 2.5shows that wave energy is proportional to

    wave height squared, e.g., a 2 m wave will carry four

    times the energy than a 1 m wave.

    Waves break as they propagate from deep water

    into shallow water. The energy that is carried by the

    wave motion is dissipated rapidly through wave break-

    ing. A large portion of this energy is expended to

    transport sediment. Due to the intense turbulence gen-

    erated by wave breaking, sediment transport associated

    with wave breaking tends to be much greater than that

    under non-breaking waves and a typical current.

    Various empirical formulas were developed to evaluate

    when waves break (Kaminsky and Kraus 1994),

    one of the simplest and also reasonably accurate

    formulas is:

    0.78

    b bH h (2.6)

    where Hb= breaking wave height, h

    b= water depth at

    which waves break. In other words, waves break when

    their height is about 80% of the water depth. Wells and

    Kemp (1986) found that muddy bottoms, typical of

    some tidal environments, can dissipate wave energy

    to such an extent that the above breaking criterion is

    never reached. Although wave forcing is secondary in

    tidal environments, it can contribute significantly to

    local sediment transport, especially in the ne