Coastal Landscapes of South Australia
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Welcome to the electronic edition of Coastal Landscapes of South Australia. The book opens with the bookmark panel and you will see the contents page. Click on this anytime to return to the contents. You can also add your own bookmarks. Each chapter heading in the contents table is clickable and will take you direct to the chapter. Return using the contents link in the bookmarks. The whole document is fully searchable. Enjoy. Coastal Landscapes of South Australia This book is available as a free fully-searchable ebook from www.adelaide.edu.au/press Published in Adelaide by University of Adelaide Press Barr Smith Library, Level 3.5 The University of Adelaide South Australia 5005 [email protected] www.adelaide.edu.au/press The University of Adelaide Press publishes peer reviewed scholarly books. It aims to maximise access to the best research by publishing works through the internet as free downloads and for sale as high quality printed volumes. © 2016 Robert P. Bourman, Colin V. Murray-Wallace and Nick Harvey This work is licenced under the Creative Commons Attribution-NonCommercial- NoDerivatives 4.0 International (CC BY-NC-ND 4.0) License. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0 or send a letter to Creative Commons, 444 Castro Street, Suite 900, Mountain View, California, 94041, USA. This licence allows for the copying, distribution, display and performance of this work for non-commercial purposes providing the work is clearly attributed to the copyright holders. Address all inquiries to the Director at the above address. For the full Cataloguing-in-Publication data please contact the National Library of Australia: [email protected] ISBN (paperback) 978-1-925261-20-2 ISBN (ebook: pdf) 978-1-925261-21-9 ISBN (ebook: epub) 978-1-925261-22-6 ISBN (ebook: kindle) 978-1-925261-23-3 DOI: http://dx.doi.org/10.20851/coast-sa Editor: Rebecca Burton Editorial support: Julia Keller Book design: Zoë Stokes Cover design: Emma Spoehr Cover image: Robert P. Bourman — View of the cliffed coast from south of Sellicks Beach towards the southern headland of Myponga Beach, Gulf St Vincent. The shore platform cuts across Oligocene-Miocene limestone of the Port Willunga Formation about 30 to 16 million years old. The limestone has been folded in plan, as shown by the curved bedding planes on the platform, and tilted at angles of up to 45° by earth movements (e.g. bottom left hand corner). Small sea stacks approximately 2 m above the shore platform have formed by erosion of an earlier, higher shore platform. A boulder beach up to 5 m high in the lower cliff zone contains marine shells of last interglacial age (125 000 years old), revealing the age of the former shore platform and providing evidence of 3 m of local tectonic uplift since the last interglacial shoreline. The modern platform is littered with boulders and pebbles derived by erosion of nearby Cambrian bedrock and Pleistocene alluvial and colluvial sediments in the cliff zone. Paperback printed by Griffin Press, South Australia This book is dedicated to Cliff Ollier for his exceptional contributions to the study of geomorphology and especially for his innovative and iconoclastic thinking. Contents Preface ix Biographies xi Acknowledgements xiii 1 Coastal landscapes of South Australia 1 2 The coast of metropolitan Adelaide 45 3 The Fleurieu Peninsula coast 71 4 The River Murray Estuary 109 5 The Coorong Coastal Plain and the 145 Limestone Coast 6 The northern Gulf St Vincent tidal 177 coastline (the Samphire Coast) 7 The Yorke Peninsula coastline 197 8 The northern Spencer Gulf coast 243 9 The Gulf Coast of Eyre Peninsula 273 10 The Bight Coast — West coast of 309 Eyre Peninsula 11 Kangaroo Island 355 12 Explaining the coastal landscapes of 387 South Australia — A synthesis Preface People have natural affinities with the sea and coastlines, using them for work, recreation and aesthetic enjoyment. Interest in coastal areas has increased with growing awareness of environmental sustainability, issues such as natural coastal vulnerability and potential climatic changes, as well as the development of a greater appreciation of impacts on coasts due to urban and industrial development. In order to make a contribution towards an understanding of the evolution of the South Australian coast and its current changes, and thereby contribute towards its better management, the authors are sharing their coastal knowledge and research. Collectively the contributors, who have been friends and academic collaborators over several decades, have accumulated a vast amount of experience related to the evolution of coastal features of South Australia. From this unique position they have synthesised this information in a manner to make it accessible to students, planners and the general public. Geologically, the South Australian coast is very young, having evolved only over 1% of geological time, during the past 43 million years since the separation of Australia and Antarctica. It is also very dynamic, with the current shoreline position having been established from only 7000 years ago. There is a remarkable diversity of coastal landscapes in South Australia, ranging through rocky cliffed coasts, submarine canyons, high wave energy sandy beaches and estuarine environments to tidally dominated coasts with sandflats and mangrove woodlands. This diversity of coastal landforms has resulted from the interaction of tides, winds and wave-generated processes operating on a range of rock types impacted by relative movements of the land and sea. Highlighting past changes at the coastline such as erosion, siltation, land movements and fluctuations in sea level provides a sound basis for understanding future changes and instigating appropriate planning strategies. Some features of the South Australian coast have national and global research significance for understanding sea level changes, coastal evolution and management by providing present analogues of past landforms. The main aim of this book is educational. By explaining the variable character of the coast and its long-term evolution, it is hoped that this book will provide people X | COASTAL LANDSCAPES OF SOUTH AUSTRALIA with background information and awaken curiosity about the coast, enabling them to understand and interpret coastal landscapes, or 'to read the coastal landscape'. They may move from wondering about the way in which the coast developed to having their own ideas, thereby heightening an appreciation of, and sensitivity towards, the dynamic character of the coast and the potential impacts of people on the coast. While much has been written about the South Australian coast, this book is unique in providing the only systematic synthesis of the long-term evolution of the South Australian coast, thereby explaining its diverse scenery. The idea for the book was spawned at an informal dinner party when the intricacies of the South Australian coast were discussed. As a result of this, Professor Cliff Ollier, to whom the book is dedicated, urged the authors to write a book summarising the geomorphic evolution of the South Australian coast. Biographies Professor Robert P. Bourman — BA (Hons, 1st Class), MA, Dip Ed, Dip T, PhD Bob Bourman, formerly Professor of Geomorphology at the University of South Australia, is currently a Visiting Professorial Fellow at the University of Wollongong and a Visiting Research Fellow at The University of Adelaide. His early training in geomorphology was at The University of Adelaide with Dr C.R. Twidale, with whom he completed an Honours Degree and an MA investigating the geomorphology of Fleurieu Peninsula, awakening nascent curiosities and precipitating a lifelong interest in geomorphology. His PhD examined the origins of ferricrete and weathered zones in southern and southeastern Australia. Professor Bourman has researched a diverse range of topics (Permian glaciation, ferricretes, inselbergs, neotectonics, river terraces and alluvial sequences, paleofloods and human impacts on the landscape), publishing some 170 peer-reviewed geomorphic papers, half of which have been related to the South Australian coast. Professor Bourman is also an educator, and he has taught in Secondary Schools and Tertiary Institutions for over 40 years. Professor Colin V. Murray-Wallace — BA (Hons), PhD, DSc, GCHEd, FGS, FRGS Colin Murray-Wallace is a Quaternary geologist and currently a Professor in the School of Earth & Environmental Sciences in the University of Wollongong. His PhD and DSc degrees are from The University of Adelaide. He has been undertaking research on aspects of the long-term geomorphological evolution of the coastline of South Australia since 1983. Colin has been particularly interested in the origin of sedimentary carbonates and the development of the vast accumulations of coastal carbonate dune deposits (aeolianite of the Bridgewater Formation) that have formed during the past 2 million years in response to repeated cycles of sea level change. His first book, Quaternary sea-level changes: A global perspective, was published by Cambridge University Press in 2014. XII | COASTAL LANDSCAPES OF SOUTH AUSTRALIA Emeritus Professor Nick Harvey — BA Hons (1st Class), B Ed, M Plan, PhD Nick Harvey is an Emeritus Professor at the University of Adelaide and an adjunct Professor in the College of Marine and Environmental Sciences at James Cook University. He is currently the Director of the Centre for Coastal Research at The University of Adelaide and Vice-President and Life Member of the