World Geomorphological Landscapes Monique Fort Marie-Françoise André Editors Landscapes and Landforms of France World Geomorphological Landscapes Series Editor: Piotr Migoń For further volumes: http://www.springer.com/series/10852 Monique Fort (cid:129) Marie-Françoise André Editors Landscapes and Landforms of France Editors Monique Fort Marie-Françoise André Geography Department, UFR GHSS Laboratory of Physical CNRS UMR 8586 PRODIG and Environmental Geography (GEOLAB) University Paris Diderot-Sorbonne-Paris-Cité CNRS – Blaise Pascal University Paris , France Clermont-Ferrand , France Every effort has been made to contact the copyright holders of the fi gures and tables which have been reproduced from other sources. Anyone who has not been properly credited is requested to contact the publishers, so that due acknowledgment may be made in subsequent editions. ISSN 2213-2090 ISSN 2213-2104 (electronic) ISBN 978-94-007-7021-8 ISBN 978-94-007-7022-5 (eBook) DOI 10.1007/978-94-007-7022-5 Springer Dordrecht Heidelberg New York London Library of Congress Control Number: 2013944814 © Springer Science+Business Media Dordrecht 2014 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfi lms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifi cally for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specifi c statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Cover illustration: © Piotr Migoń Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) Series Edito r Preface Landforms and landscapes vary enormously across the Earth, from high mountains to endless plains. At a smaller scale, nature often surprises us, creating shapes which look improbable. Many physical landscapes are so immensely beautiful that they received the highest possible recognition – they hold the status of World Heritage properties. Apart from often being immensely scenic, landscapes tell stories which not uncommonly can be traced back in time for tens of million years and include unique events. In addition, many landscapes owe their appearance and harmony not solely to the natural forces. Since centuries, or even millennia, they have been shaped by humans who modifi ed hillslopes, river courses, and coastlines, and erected structures which often blend with the natural landforms to form inseparable entities. These landscapes are studied by geomorphology – ‘the science of scenery’ – a part of Earth sciences that focuses on landforms, their assemblages, and surface and subsurface processes that moulded them in the past and that change them today. Shapes of landforms and regulari- ties of their spatial distribution, their origin, evolution, and ages are the subject of research. Geomorphology is also a science of considerable practical importance since many geomorphic processes occur so suddenly and unexpectedly, and with such a force, that they pose signifi cant hazards to human populations and not uncommonly result in considerable damage or even casualties. With this book focused on France, we launch a new book series World Geomorphological Landscapes . It aims to be a scientifi c library of monographs that present and explain physical landscapes across the globe, focusing on both representative and uniquely spectacular examples. Each book will contain details on geomorphology of a particular country or a geographically coherent region. The core of each book is a succinct presentation of key geomorphological localities (landscapes), representative for the geomorphic diversity of each country. Written in easy-to-read language, the landform evolution stories presented in each volume give together an overview of what each particular country has to offer. But they can also serve as a guidance for holidaymaking geoscientists as to where to go to enjoy the best of geomorphology. The series is thus a unique reference source not only for geomorphologists, but all Earth scientists, geographers, and conservationists. It complements the existing reference books in geomorphology which focus on specifi c themes rather than regions or localities and fi lls a growing gap between poorly accessible regional studies, often in national languages, and papers in international journals which put major emphasis on understanding processes rather than particular landscapes. The World Geomorphological Landscapes series is produced under the scientifi c patronage of the International Association of Geomorphologists – a society that brings together geomor- phologists from all around the world. The IAG was established in 1989 and is an independent scientifi c association affi liated at the International Geographical Union and the International Union of Geological Sciences. Among its main aims are to promote geomorphology and to foster dissemination of geomorphological knowledge. I believe that this lavishly illustrated series, which however sticks to the scientifi c rigour, is a most appropriate means to fulfi l these aims and to serve the geoscientifi c community. Series Editor Piotr Migoń v Foreword France presents a wide variety of landscapes, both natural and cultural, making this country the most visited in the world (Chap. 1 ) . If we consider physical aspects of the landscape, this variety can be explained by a series of factors: (1) the topographical contrasts, from the highest summit of Europe down to the ocean; (2) a comprehensive collection of rock types (Fig . 1) and their related morphostructural units (sedimentary basins, basement uplands, active orogens, faulted systems with volcanism, coastal plains, deltas and marshes); (3) the long geological history and the succession of bioclimatic environments from tropical to glacial and periglacial environments, which left their imprint in the landscape; and (4) the large present-day biocli- matic diversity, at the junction of the Atlantic, Continental, and Mediterranean infl uences, which gives the geomorphological landscapes different atmospheres and lights (e.g. Brittany compared with French Riviera). Prehistoric and historical (including Roman) legacies are also an integral part of French landscapes and landforms, often requiring a geoarcheological approach to better appreciate the role of early cultural groups in modelling their environment, exploiting their resources, and understanding the advantages of specifi c sites beyond their potential constraints or haz- ards. In that respect, two major characteristics should be highlighted. First, the abundance of limestone plateaus in the south of France explains both the number of beautifully orna- mented caves and the wall paintings left by prehistoric humans as they sought sheltered sites during the last glaciation. Second, the combination of suitable soils and well-exposed slopes made France the country of viticultural ‘terroirs’, often developed on south- or southeast- facing scarps ensuring a good drainage and a sunny atmosphere whatever their structural origin: fault steps of Alsace, Burgundy, or Rhone Valley, cuesta of Champagne or thrust front of the western Jura. T his book is intended to provide the reader with an overview of French landscapes and landforms, refl ecting as far as possible their diversity. To date, France is a country endowed with 34 sites inscribed as cultural heritage sites on the UNESCO World Heritage list, often backed by exceptional natural sites (e.g. Mont St-Michel (Chap. 5 ) or Paris and the banks of the Seine River (Chap. 2 ) ). On the other hand, only three sites have been inscribed as natural heritage sites, including Corsican granitic landscapes (Chap. 2 3 ) and La Reunion volcanic landforms (Chap. 2 5 ) , whereas the mixed ‘Cultural and Natural Heritage’ label is recognised in one site only (Gavarnie in the Pyrenees (Chap. 1 2 ) ). Many chapters of this book deal with World Heritage Sites (WHS), either already listed by UNESCO or currently under consider- ation for UNESCO label recognition (e.g. Mont Blanc Massif, Chaîne des Puys volcanoes, Chauvet Cave – Pont d’Arc, and Camargue). Others have already received the label of ‘Grands Sites de France’: this is the case of Aven d’Orgnac (Chap. 1 9 ) , Massif du Canigou (Chap. 1 3 ) , and Cirque de Navacelles (Chap. 1 1 ) . These UNESCO WHS and ‘Grands Sites de France’ are shown in Fig. 2. vii viii Foreword Fig. 1 Main geological frame of the different areas described in this book, with numbers refering to chapters (Drawing F. Bétard) The book is organised in a sequence of chapters according to the following itinerary. Starting from Paris (Chap. 2 ), founded by the Romans, it is shown how in its early develop- ment the capital city benefi ted from links along the Seine River that favoured fl uvial trade and from its substrate that offers abundant resource for building stones. Chapter 3 describes the famous entrenched meanders of the Seine River Valley downstream of Paris, developed under Foreword ix the alternation of glacial/interglacial periods: rich in mediaeval castles built on the chalk cliffs, the valley later attracted many Impressionist painters (Fig. 2 ). The high Normandy coast and cliffs (Chap. 4 ), with their imposing verticality, their whiteness varying in tone with the ever-changing light and tide, and their ghostly shapes, also exerted a powerful attraction to painters and novelists. The instability of the cliffs has become a real concern for policymakers. Quite different is the Mont Saint-Michel bay (Chap. 5 ), characterised by its exceptional tidal range and the immensity of its tidal fl at, overlooked by the Abbey perched on an island of which integrity is endangered by the progress of sedimen- tation. In contrast, the celebrated Pink Granite coast of northern Brittany (Chap. 6 ) illustrates both the infl uence of selective weathering under terrestrial conditions and the stripping of the saprolite by marine processes. The Loire River Valley (Chap. 7 ), famous for its vineyards and royal châteaux, is much wider than the Seine Valley, and in its lower part it consists of a patchwork of geomorphic compartments (islands, separated by multiple branches of the river) that are remodelled under the infl uence of fl oods originating from the Massif Central highlands. Arcachon Bay (Chap. 8 ) is already part of southern France: bordered by the largest coastal dune belt in Europe, it is a typical semi-sheltered lagoon located on the Atlantic coast of France, facing the wave- dominated coast of the Bay of Biscay. It has become a famous oyster cultivation area and hosts various recreational activities (sport-fi shing, sailing, and ecotourism) all year around. The volcanic C haîne des Puys range (Chap. 9 ) displays a wide spectrum of potentially active volcano types, very attractive for scientists, students, and visitors. Used for grazing as far back as the Neolithic period, and more intensively since the Roman Empire, volcanic slopes have been heavily deforested and eroded. With its status of French Regional Nature Park acquired in 1977, the Chaîne des Puys has been protected ever since. To the south, the Velay and its Vivarais rim (Chap. 1 0 ) combine many historical aspects of the Massif Central, from its Hercynian basement to the Tertiary tectonic and volcanic reactivations following the Pyrenean and Alpine orogenies, and from the Mesozoic and Tertiary planations to the Plio- Quaternary excavation of valleys. With the Cirque de Navacelles (Chap. 1 1 ), we have a perfect example of a meander incised by the Vis River in its gorge across the Causse du Larzac (limestone plateau), downstream from the metamorphic and granitic Cévennes Mountains. Yet it is much more complex than a simple bend in a watercourse, as karstic infl uence contributed to its evolution. Overlooked by panoramic viewpoints, it is listed on the ‘Grand sites de France’. The Cirque de Gavarnie (Chap. 12 ), a 1,500-m-high limestone theatre, is an exceptional landscape recognised in 1997 as a UNESCO World Heritage site for both its natural and cultural values. It results from a long evolution, including the formation of the Pyrenean range, the combination of both karstic and glacial infl uences, and a long history of human occupation and exchanges across the French-Spanish border. In the Eastern Pyrenees (Chap. 1 3 ), where the Mediterranean and Atlantic biomes meet, the Têt river catchment displays a spectacular suite of tectonic, glacial, periglacial, fl uvial, and hillslope forms. Famous for its prominent fragments of smooth, pre-Quaternary Paleic relief remnants where glacial erosion has not serrated the interfl uves, this Mediterranean part of the Pyrenees also preserves good records of post- orogenic landscape evolution and base-level changes since the early Neogene. The Vosgian-Alsatian side of the Rhine Graben (Chap. 1 4 ) developed in response to Alpine orogeny: it is a unique, tectonically controlled landscape, famous for its vineyards and its traditional well-preserved architecture and culture. Nearby, the Jura Massif (Chap. 1 5 ) displays in its external part an original fold-and-thrust belt overriding the Bresse graben and bearing famous vineyards, in addition to scenic blind valleys, exsurgence springs and glacially formed lakes with Neolithic pile-dwelling settlements. The Vosges Mountains (Chap. 1 6 ) formed in uplifted Hercynian basement, affected by Quaternary glaciation. Upon its bald, rounded summit ridges, heathland and meadows with specifi c vegetal communities result from deforestation