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Database of Pleistocene Periglacial Featuresin France Quaternaire Revue de l'Association française pour l'étude du Quaternaire vol. 27/4 | 2016 Volume 27 Numéro 4 Database of pleistocene periglacial features in France: description of the online version Base de données des structures périglaciaires pléistocènes en France : description de la version accessible en ligne Eric Andrieux, Pascal Bertran, Pierre Antoine, Laurent Deschodt, Arnaud Lenoble, Sylvie Coutard, Aurelie Ajas, Quentin Borderie, Jean-Pierre Coutard, Francois Didierjean, Bertrand Dousteyssier, Catherine Ferrier, Philippe Gardère, Thierry Gé, Morgane Liard, Jean‑Luc Locht, Henri‑Georges Naton, Mathieu Rue, Luca Sitzia, Brigitte Van Vliet-Lanoe and Gérard Vernet Electronic version URL: http://journals.openedition.org/quaternaire/7717 DOI: 10.4000/quaternaire.7717 ISSN: 1965-0795 Publisher Association française pour l’étude du quaternaire Printed version Date of publication: 1 December 2016 Number of pages: 329-339 ISSN: 1142-2904 Electronic reference Eric Andrieux, Pascal Bertran, Pierre Antoine, Laurent Deschodt, Arnaud Lenoble, Sylvie Coutard, Aurelie Ajas, Quentin Borderie, Jean-Pierre Coutard, Francois Didierjean, Bertrand Dousteyssier, Catherine Ferrier, Philippe Gardère, Thierry Gé, Morgane Liard, Jean‑Luc Locht, Henri‑Georges Naton, Mathieu Rue, Luca Sitzia, Brigitte Van Vliet-Lanoe and Gérard Vernet, « Database of pleistocene periglacial features in France: description of the online version », Quaternaire [Online], vol. 27/4 | 2016, Online since 01 December 2018, connection on 16 December 2019. URL : http://journals.openedition.org/quaternaire/ 7717 ; DOI : 10.4000/quaternaire.7717 © Tous droits réservés Quaternaire, 27, (4), 2016, p. 329-339 DATABASE OF PLEISTOCENE PERIGLACIAL FEATURES IN FRANCE: DESCRIPTION OF THE ONLINE VERSION n Eric ANDRIEUX1, Pascal BERTRAN2, 1, Pierre ANTOINE3, Laurent DESCHODT4, Arnaud LENOBLE1, Sylvie COUTARD5 & collaborators* ABSTRACT A database of Pleistocene periglacial features in France has been compiled from a review of academic literature and reports of rescue archaeology, the analysis of aerial photographs and new field surveys. Polygons, soil stripes, ice-wedge pseudomorphs, sand wedges and composite wedge pseudomorphs are included in the database together with their geographic coordinates, geolo- gical context, description and associated references. It is hoped that this database, which aim is to be integrated in broader studies, will stimulate further work on past permafrost reconstruction and will favour greater understanding of the climatic events that lead to the formation of the periglacial features. The database is available online on the AFEQ-CNF INQUA website (https://afeqeng. hypotheses.org/487). A folder that contains photographs and sketches of the features is also available on request. Keywords: permafrost, ice-wedge pseudomorphs, sand wedges, composite wedge pseudomorphs, polygons, soil stripes, France RÉSUMÉ BASE DE DONNÉES DES STRUCTURES PÉRIGLACIAIRES PLÉISTOCÈNES EN FRANCE : DESCRIPTION DE LA VERSION ACCESSIBLE EN LIGNE Une base de données des structures périglaciaires pléistocènes de France a été créée à partir d’une revue de la littérature scientifique, de rapports d’archéologie préventive, de l’analyse de photographies aériennes et de nouvelles prospections de terrain. Les polygones, les sols striés, les pseudomorphoses de coin de glace, les coins de sable et les pseudomorphoses de coin composite ont été répertoriés dans la base de données avec leurs coordonnées géographiques, le contexte géologique, leur description et les références bibliographiques associées. Nous espérons que cette base de données, dont le but est d’être intégrée dans des études plus larges, stimulera de prochains travaux sur la reconstitution du pergélisol pléistocène et favorisera une plus grande compréhension des événements climatiques qui ont conduit à la formation de ces structures périglaciaires. La base de données est disponible en ligne sur le site de l’AFEQ-CNF INQUA (https://afeqeng.hypotheses.org/487). Un dossier contenant les photographies et dessins des structures périglaciaires est également disponible sur demande. Mots-clés : pergélisol, pseudomorphoses de coin de glace, coins de sable, pseudomorphoses de coin composite, polygones, sols striés, France 1 - INTRODUCTION tific community focused on the climatic significance of the features, the reconstruction of past environments, and During the Pleistocene, periglacial landscapes have finally, the possible impact of the periglacial milieus on formed over large surfaces in mid-latitude Western Palaeolithic populations. Europe. The Mid to Late Pleistocene climate oscillations Reconstructions of the previous extent of permafrost caused the land area affected by periglacial conditions to in Western Europe have been proposed for over 60 years expand and contract repeatedly. Many relict periglacial (Poser, 1948; Büdel, 1951; Kaiser, 1960; Maarleveld, features bear witness of these events and raised abundant 1976; Lautridou & Sommé, 1981; Velichko, 1982). research by geologists and geomorphologists. Aside from Further improvements were later made using increa- the engineering aspects of these discoveries, the scien- singly available observations on present-day permafrost 1 PACEA, UMR 5199 Université de Bordeaux – CNRS, Bâtiment B18, Allée Geoffroy-Saint-Hilaire, CS 50023, FR-33615 Pessac cedex. Courriel : [email protected] 2 INRAP, 140 avenue du Maréchal Leclerc, FR-33130 Bègles. Courriel : [email protected] 3 LGP, UMR 8591 Université Paris 1 – CNRS, 1 place A. Briand, FR-92195 Meudon cedex. Courriel : [email protected] 4 INRAP, 11 rue des champs, ZI de la Pilaterie, FR-59650 Villeneuve-d’Ascq. Courriel : [email protected] 5 INRAP, 518 rue Saint-Fuscien, FR-80090 Amiens. Courriel : [email protected] * Aurélie AJAS, Quentin BORDERIE, Jean-Pierre COUTARD, François DIDIERJEAN, Bertrand DOUSTEYSSIER, Catherine FERRIER, Philippe GARDÈRE, Thierry GÉ, Morgane LIARD, Jean-Luc LOCHT, Henri-Georges NATON, Mathieu RUÉ, Luca SITZIA, Brigitte VAN VLIET-LANOË, Gérard VERNET. Manuscrit reçu le 18/05/2016, accepté le 20/07/2016 1609-106-Mep4-2016.indd 329 21/11/16 14:34 330 (Péwé, 1966; Romanovskij, 1985; Mackay & Burn, Multi-user tests were performed on the photographs to 2002; Murton, 2013), and sporadic, discontinuous and be sure that only indisputable features were added to the continuous Pleistocene permafrost was differentiated database. When different features were present on the in the proposed maps (Vandenberghe & Pissart, 1993; same site, it appears in the file of the most represented Van Vliet-Lanoë, 1989, 1996; Huijzer & Vandenberghe type. Search for periglacial features in aerial photo- 1998; Isarin et al., 1998; Van Vliet & Hallégouët, 2001; graphs have been made primarily in areas where some Renssen and Vandenberghe, 2003; Vandenberghe et al., had been previously reported in the literature. Search 2014). Despite the lack of agreement between these was then extended to neighbouring regions. In this reconstructions, these studies agree that permafrost process, it became rapidly obvious that many features extended over large parts of France during the Pleisto- were preferentially associated with specific substrates, cene. for example old (Lower Pleistocene and Tertiary) allu- Most of the datasets available have been published vial sand and gravel deposits for polygons, chalk with in French language with limited circulation, and unfor- a thin loess cover for soil stripes… Blind tests in other tunately remains largely inaccessible to the interna- regions were also made but were most of the time unsuc- tional community. During the last decade, the launch of cessful. online databases of aerial photographs (Google earth, We also conducted a thorough search of the published Géo portail) has eased the recognition of periglacial literature on periglacial features in France, including features, adding a lot of new data. The huge development articles in journals, PhD theses, other dissertations (often of rescue archaeology also increased significantly the unpublished) and geology reports of rescue archaeology. number of identified features. These data were rigorously selected and all entries not This paper serves as an introduction to an online data- accompanied by drawings, photographs or good descrip- base aiming at gathering as exhaustively as possible the tions were rejected from the database. We were forced features related to past permafrost in France, to give to exclude a significant amount of features because the easier access to a homogenised and reliable dataset. It sources did not document them enough (lack of descrip- also reports on the main limits that should be considered tion or figure) ordid not give satisfying geographic infor- when using the map or the data to make interpretations. mation (e.g. coordinates, grid references). The establishment of such a database is of the outmost The investigated literature covers the last 60 years, importance to progress towards a better general unders- and during such a time span the overall understanding tanding of periglacial environments. and classification of the periglacial processes changed The database was first introduced yb Bertran et al. significantly. In the 50’s, the research community lead (2014), who focused on the geographic distribution by A. Cailleux and J. Tricart (Bastin & Cailleux, 1941; of the georeferenced features and reviewed the avai- Cailleux, 1948, 1956; Tricart, 1963; Tricart & Cailleux, lable chronological data. Periglacial
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