Stages of Sedimentary Infilling in a Hypertidal

Total Page:16

File Type:pdf, Size:1020Kb

Stages of Sedimentary Infilling in a Hypertidal Stages of sedimentary infilling in a hypertidal bay using a combination of sedimentological, morphological and dynamic criteria (Bay of Somme, France) Charlotte Michel, Sophie Le Bot, Flavie Druine, Stéphane Costa, Franck Levoy, Carole Dubrulle-Brunaud, Robert Lafite To cite this version: Charlotte Michel, Sophie Le Bot, Flavie Druine, Stéphane Costa, Franck Levoy, et al.. Stages of sedimentary infilling in a hypertidal bay using a combination of sedimentological, morphological and dynamic criteria (Bay of Somme, France). Journal of Maps, Taylor & Francis, 2017, 13 (2), pp.858-865. 10.1080/17445647.2017.1389663. hal-02119165 HAL Id: hal-02119165 https://hal.archives-ouvertes.fr/hal-02119165 Submitted on 3 May 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Journal of Maps ISSN: (Print) 1744-5647 (Online) Journal homepage: http://www.tandfonline.com/loi/tjom20 Stages of sedimentary infilling in a hypertidal bay using a combination of sedimentological, morphological and dynamic criteria (Bay of Somme, France) Charlotte Michel, Sophie Le Bot, Flavie Druine, Stéphane Costa, Franck Levoy, Carole Dubrulle-Brunaud & Robert Lafite To cite this article: Charlotte Michel, Sophie Le Bot, Flavie Druine, Stéphane Costa, Franck Levoy, Carole Dubrulle-Brunaud & Robert Lafite (2017) Stages of sedimentary infilling in a hypertidal bay using a combination of sedimentological, morphological and dynamic criteria (Bay of Somme, France), Journal of Maps, 13:2, 858-865, DOI: 10.1080/17445647.2017.1389663 To link to this article: http://dx.doi.org/10.1080/17445647.2017.1389663 © 2017 The Author(s). Published by Informa View supplementary material UK Limited, trading as Taylor & Francis Group on behalf of Journal of Maps Published online: 26 Oct 2017. Submit your article to this journal Article views: 24 View related articles View Crossmark data Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=tjom20 Download by: [Rouen University] Date: 06 November 2017, At: 04:01 JOURNAL OF MAPS, 2017 VOL. 13, NO. 2, 858–865 https://doi.org/10.1080/17445647.2017.1389663 SCIENCE Stages of sedimentary infilling in a hypertidal bay using a combination of sedimentological, morphological and dynamic criteria (Bay of Somme, France) Charlotte Michela, Sophie Le Bot a, Flavie Druinea, Stéphane Costa b, Franck Levoyc, Carole Dubrulle- Brunaud c and Robert Lafite a aNormandie University, UNIROUEN, UNICAEN, CNRS, M2C, 76000 Rouen, France; bNormandie University, UNICAEN, CNRS, LETG, 14000 Caen, France; cNormandie University, UNICAEN, UNIROUEN, CNRS, M2C, 14000 Caen, France ABSTRACT ARTICLE HISTORY In the context of rising sea level, many estuaries and bays show an overall trend to sedimentary Received 10 January 2017 infilling. Among these coastal environments, the Bay of Somme is a hypertidal tide and wave- Accepted 4 October 2017 dominated estuary, filled in by marine sands, with a superficy of 70 km2. This study proposes a KEYWORDS spatial zonation of the intertidal area of the bay based on the combination of information on Sedimentary infilling; sediments, seabed morphology and dynamics. Data come from a surficial sediment sampling – sediment dynamics; campaign and six airborne LiDAR topographic surveys, acquired over the period 2011 2013, sediment grain-size; providing information on grain size, carbonate content, bedform occurrence and seabed hydraulic dunes; hypertidal dynamics. The Main Map shows the morpho-sedimentary and -dynamic zonation used as a estuary; intertidal; LiDAR; basis to describe infilling stages in the bay. Bay of Somme 1. Introduction Littoral Picard, 2011), is located on the French coast Currently, many estuaries and bays are being filled with of the Eastern English Channel. It is the biggest estuar- sediment since the Holocene transgression (Anthony, ine bay of Picardy (70 km²), with a mixed energy 2002; Davis & Fitzgerald, 2004; Dyer, 1986; Gibbard regime, influenced by both tides and waves: the tide & Lautridou, 2003; Green & MacDonald, 2001; Harris, has a hypertidal range (8.5 m in mean spring con- 1988; Jago, 1980; Moore, Wolf, Souza, & Flint, 2009; ditions, up to 10.55 m in case of exceptional tides) Nichols & Biggs, 1985; Paphitis, Bastos, Evans, & and prevailing waves are of west provenance (75% of Collins, 2010; Psuty & Silveira, 2009; Tessier, Billeaud, the time) with mean significant wave height and period Sorrel, Delsinne, & Lesueur, 2012). The characteriz- around 2 m and 7 s, respectively, along the littoral of ation of the degrees of sedimentary infilling and the Cayeux-sur-Mer. These weather-marine forcings con- quantification of its rates constitute an important trol the infilling of the bay by marine sands (Dupont, information in order: (i) to better understand past evol- 1981), derived from the sedimentary prism of Picardy ution of estuaries, and (ii) to forecast future landscape, (Ferret, Le Bot, Tessier, Garlan, & Lafite, 2010), and habitat and usage modifications for an adapted by an important endemic bioclastic production management. (Desprez, Olivesi, Duhamel, Loquet, & Rybarczyk, Downloaded by [Rouen University] at 04:01 06 November 2017 Sea-level rise rate, bedrock morphology, sediment 1998). A sand bulge occupies the bay, which is fully supply and sediment transport rate are the main con- located in the intertidal domain. The seabed of the trolling factors of the general infilling pattern of estu- Bay of Somme is characterized by: (1) a uniform and aries and bays (Tessier et al., 2012). According to relatively flat beach (almost devoid of bedforms) con- Harris (1988), bedforms (e.g. sandbanks, hydraulic necting the Pointe de St-Quentin to the Crotoy; (2) dunes, tidal flats) can constitute a source of infor- tidal channels; (3) sand banks; (4) sedimentary bars mation on the stages of sedimentary infilling of bays systems and (5) more than 4200 hydraulic dunes and on the directions of sediment transport. Estuary arranged in fields and usually covered with ripples evolution is mainly driven by bedform evolution, (Michel, 2016). Two rivers flow into the bay: the which is strongly controlled by sediment dynamics Somme river (mean flow rate of 32 m3/s) to the east on the estuarine bed, itself dependent on sediment of the bay, channeled from Abbeville to Saint-Valery- characteristics (Boyd, Dalrymple, & Zaitlin, 1992; sur-Somme, and the Maye river (mean flow rate of Green & MacDonald, 2001; Jarvis & Riley, 1987). 1.5 m3/s) leading to the north of the bay. They bring − The Bay of Somme, ranked 10th ‘Grand Site de low amounts of fine particles (67 800 T year 1 from France®’ (Syndicat Mixte Baie de Somme Grand the Somme river; Loquet, Rybarczyk, & Elkaim, CONTACT Sophie Le Bot [email protected] Normandie University, UNIROUEN, UNICAEN, CNRS, M2C, 76000 - Rouen, France © 2017 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of Journal of Maps This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. JOURNAL OF MAPS 859 2000), which deposit on salt marshes (altitude beyond altimeter system IGN69. They cover the intertidal area + 4 m NGF-IGN69). with a vertical accuracy of ±0.15 m for the February– In this study, an interpretative map of the morpho- March 2011 data and ±0.08 m for the other surveys sedimentary and -dynamic characteristics of the Bay of (28 September 2011 to 11 April 2013), except in Somme is proposed, based on the combination of data water areas in which the LiDAR signal does not pene- on seabed dynamics and bedform occurrence, obtained trate (e.g. bottom of tidal channels, hunting ponds in from airborne LiDAR topographic surveys, and refined salt marshes, lowest areas of the intertidal zone, subti- with sedimentary data (grain-size parameters, carbon- dal areas). These topographic LiDAR data have been ate content) derived from surficial sediment sampling used to perform the mapping of the morphology and (Main Map). On the basis of these sedimentological, the dynamics of the bay. morphological and dynamic criteria, the definition of sectors with homogeneous morpho-sedimentary and 2.2. Cartography and computer graphics -dynamic characteristics allows to propose a zonation of the Bay of Somme, which can be then used as a Maps were realized from the sediment and topographic spatial framework to describe the different infilling data by means of ArcGIS10 (© ESRI) and Adobe® Illus- stages in the bay. trator® CS6 Tryout (© Adobe Systems Inc.) softwares. The sedimentary facies map (Figure 1), established according to the classification of Folk (1965), was 2. Methods built as a shapefile of polygons drawn by hand. All other sedimentary maps (mean grain size on Main 2.1. Data Map; mud and fine sand contents, sorting, CaCO3 A total of 246 surficial sediment samples were realized content on Figure 1) correspond to rasters created on the sandy seabed of the bay, between 13 February using kriging interpolation proposed in ArcGIS10 2013 and 22 August 2013, at a mean sampling interval (© ESRI), with a resolution of 1 m. On the Sediment of 500 m. Most of the areas were reached by foot and Map (Main map), sedimentary zones were delimitated samples were collected by hand in the first 4 cm. For on the basis of the distribution of mean grain size, the water areas (tidal channels, the western border of which is a synthetic sediment parameter, and content the intertidal domain), samples were collected with in fine sands, which is the most represented sedimen- an Ekman grab from a zodiac.
Recommended publications
  • American Armies and Battlefields in Europe
    Chapter v1 THE AMERICAN BATTLEFIELDS NORTH OF PARIS chapter gives brief accounts of areas and to all of the American ceme- all American fighting whi ch oc- teries and monuments. This route is Thiscurred on the battle front north of recommended for those who desire to Paris and complete information concern- make an extended automobile tour in the ing the American military cemeteries and region. Starting from Paris, it can be monuments in that general region. The completely covered in four days, allowing military operations which are treated are plenty of time to stop on the way. those of the American lst, 27th, 30th, The accounts of the different operations 33d, 37th, 80th and 91st Divisions and and the descriptions of the American the 6th and 11 th Engineer Regiments. cemeteries and monuments are given in Because of the great distances apart of the order they are reached when following So uthern Encr ance to cb e St. Quentin Can al Tunnel, Near Bellicourc, October 1, 1918 the areas where this fighting occurred no the suggested route. For tbis reason they itinerary is given. Every operation is do not appear in chronological order. described, however, by a brief account Many American units otber tban those illustrated by a sketch. The account and mentioned in this chapter, sucb as avia- sketch together give sufficient information tion, tank, medical, engineer and infantry, to enable the tourist to plan a trip through served behind this part of the front. Their any particular American combat area. services have not been recorded, however, The general map on the next page as the space limitations of tbis chapter indicates a route wbich takes the tourist required that it be limited to those Amer- either int o or cl ose to all of tbese combat ican organizations which actually engaged (371) 372 THE AMERICAN B ATTLEFIELD S NO R TH O F PARIS Suggested Tour of American Battlefields North of Paris __ Miles Ghent ( î 37th and 91st Divisions, Ypres-Lys '"offensive, October 30-November 11, 1918 \ ( N \ 1 80th Division, Somme 1918 Albert 33d Division.
    [Show full text]
  • Amiens
    Amiens < Somme < Picardie < France Amiens Amiens Metropolitan Tourist Office greets you Monday to Saturday 9.30 a.m. to 6.30 p.m. (6 p.m. October 1 to March 31) - Focus on the city Sunday 10 a.m. to 12 noon and 2 to 5 p.m. Amiens Metropolitan Tourist Office aison, L.Rousselin, Parc zoologique - Amiens Métropole, A.S. Flament, zoologique - Amiens Métropole, aison, L.Rousselin, Parc Information desk : 40, Notre-Dame square BP 11018 - F - 80010 Amiens cedex 1 Tél.: +33(0)322716050 • Fax: +33(0)322716051 www.visit-amiens.com [email protected] ACCUEIL ET INFORMATION DES OFFICES DE TOURISME ET SYNDICAT D’INITIATIVE Cette marque prouve la conformité à la norme NF X 50-730 et aux règles 5284 2010 03 22 80 50 20 Crédit photosM B. © www.tibo.org. : © SKERTZÒ. de certification NF 237. Elle garantit que l’accueil et l’information des clients, la promotion et la communication, la production et la commercialisation, la boutique, l’évaluation et l’amélioration de la qualité de service sont contrôlés régulièrement par AFNOR CERTIFICATION 11, rue Francis de Préssensé – 93571 SAINT DENIS LA PLAINE Cedex – France – www.marque-nf.com www.grandnord.fr Amiens Tours of Amiens Visits Notre-Dame cathedral and surrounding areas • The Cathedral is open all year • round ; guided visits, audio- • Amiens Notre-Dame Cathedral has been For more information about Starting in front of the Cathedral, from April to September, the Samarobriva barou- guides and access to the described in the following terms: light, the Somme department, ches will take you on a discovery ride of towers throughout the year perfection… built to harmonious proportions.
    [Show full text]
  • The Earliest Evidence of Acheulian Occupation in Northwest
    www.nature.com/scientificreports OPEN The earliest evidence of Acheulian occupation in Northwest Europe and the rediscovery of the Moulin Received: 5 December 2017 Accepted: 19 August 2019 Quignon site, Somme valley, France Published: xx xx xxxx Pierre Antoine1, Marie-Hélène Moncel2, Pierre Voinchet2, Jean-Luc Locht1,3, Daniel Amselem2, David Hérisson 4, Arnaud Hurel2 & Jean-Jacques Bahain2 The dispersal of hominin groups with an Acheulian technology and associated bifacial tools into northern latitudes is central to the debate over the timing of the oldest human occupation of Europe. New evidence resulting from the rediscovery and the dating of the historic site of Moulin Quignon demonstrates that the frst Acheulian occupation north of 50°N occurred around 670–650 ka ago. The new archaeological assemblage was discovered in a sequence of fuvial sands and gravels overlying the chalk bedrock at a relative height of 40 m above the present-day maximal incision of the Somme River and dated by ESR on quartz to early MIS 16. More than 260 fint artefacts were recovered, including large fakes, cores and fve bifaces. This discovery pushes back the age of the oldest Acheulian occupation of north-western Europe by more than 100 ka and bridges the gap between the archaeological records of northern France and England. It also challenges hominin dispersal models in Europe showing that hominins using bifacial technology, such as Homo heidelbergensis, were probably able to overcome cold climate conditions as early as 670–650 ka ago and reasserts the importance of the Somme valley, where Prehistory was born at the end of the 19th century.
    [Show full text]
  • Le Guide Couleurs Lumières Respirer Rencontres Paysages Expériences Sauvages
    SLOW LE GUIDE COULEURS LUMIÈRES RESPIRER RENCONTRES PAYSAGES EXPÉRIENCES SAUVAGES baie-somme.com Sommaire © JF Rouge Une reconnaissance mondiale 4 Accès 7 La Baie de Somme 8 • Saint-Valery-sur-Somme 11 • Le Chemin de Fer de la Baie de Somme 12 • Le Crotoy 14 • Le Marquenterre 16 • L’Abbaye de Saint-Riquier 18 • Rue Cette brochure est le fruit d’un travail collaboratif et d’un cofinancement 19 • Crécy-en-Ponthieu réunissant l’Agence de Développement et de Réservation Touristiques 20 • Quend-Plage de la Somme, la Communauté d’Agglomérations Baie de Somme, 21 • Fort-Mahon-Plage la Communauté de Communes Ponthieu Marquenterre, le Syndicat Mixte Baie 22 • L’Abbaye et les jardins de Valloires de Somme Grand Littoral Picard, le Syndicat Mixte Baie de Somme 3 Vallées, 23 • Vallée de l’Authie la Communauté de Communes du Vimeu, la Communauté de Communes • Cayeux-sur-Mer des Villes-Sœurs et le Conseil 24 Départemental de la Somme. • La Maison de la Baie de Somme Ce magazine gratuit est édité 26 en février 2019 par Somme Tourisme. 54 rue Saint-Fuscien 27 • Le Vimeu 80000 Amiens 03 22 71 22 71 28 • Ault [email protected] somme-tourisme.com 29 • Mers-les-Bains Tous nos soins ont été apportés • La Côte d’Albâtre à la réalisation de cet ouvrage. 30 Toutefois, nous déclinons toute responsabilité pour les erreurs 32 • La Vallée de la Bresle ou omissions qui auraient pu se glisser dans le texte ou parmi les photographies. 33 • Le château-fort de Rambures La jurisprudence (Cour de Toulouse 14-01-1987, Tribunal de la Seine 27-08-1888, 34 • Abbeville Tribunal de Commerce de Marseille 27-12- © Tibo 1908) décide en eet que les éditeurs 38 • La Vallée de la Somme d’un guide ne sont pas responsables des erreurs ou omissions commises involontairement dans l’ouvrage.
    [Show full text]
  • The Marshlands of Méricourt-Sur-Somme
    Boisement Water Chipilly Belvedere (viewpoint) Prairie-Pâture Agricultural land Larris Wooded areas Espace urbanisé Wetlands at the bottom of the valley Somme Canal Reed Beds Lock-keeper’s House Départ Eglise de Le-Quesne Wooden foot-bridge me Un des points de vue les m plus hauts de la Somme o Starting Point S D Lock-keeper’s house at d l Méricourt-sur-Somme O Préservons la nature Vous participez à la conservation de la richesse P Car Park de ce site fragile : . en empruntant les sentiers, . en refermant les passe-clôtures après votre passage, ! Be careful: . en respectant sa faune et sa flore, Hunting is carried out on . en emportant vos déchets en quittant le site. this site during the official P Rannou © S. hunting period. Please be careful during this period. Starting at: Car park at Protect the natural The Marshlands of the lock-keeper’s house at Méricourt-sur-Somme Méricour environment D To help with the conservation of the rich natural habitats of this fragile Méricourt-sur-Somme t-sur site, please: Time: 30 mins Méricourt-sur-Somme, By visiting the marshlands of -Somme . Always use the marked trails . Keep gates and stiles closed 8km from Bray-sur-Somme, Méricourt, nature will reveal all of its . Respect the fauna and flora 31km from Amiens beauty. Hiking, hunting, fishing, and nature Distance: 1,5km . Take your litter away with you discovery activities - something N 0 50 100m for everyone. This trail is maintained by Route: easy the Poppy Country Sign posts Route continues Wrong direction Change of direction For more information:
    [Show full text]
  • Article Aims at Answering the Following Derstand the 2001 flooding (Hubert, 2001; Pointet Et Al., Questions: 2003; Negrel´ and Petelet-Giraud´ , 2005)
    Hydrol. Earth Syst. Sci., 14, 99–117, 2010 www.hydrol-earth-syst-sci.net/14/99/2010/ Hydrology and © Author(s) 2010. This work is distributed under Earth System the Creative Commons Attribution 3.0 License. Sciences Multi-model comparison of a major flood in the groundwater-fed basin of the Somme River (France) F. Habets1,2, S. Gascoin2, S. Korkmaz3, D. Thiery´ 4, M. Zribi5, N. Amraoui4, M. Carli2, A. Ducharne2, E. Leblois6, E. Ledoux3, E. Martin1, J. Noilhan1, C. Ottle´5,7, and P. Viennot3 1GAME/CNRM (Met´ eo-France/CNRS),´ URA 1357, Toulouse, France 2UMR-Sisyphe, UMR 7619, Sisyphe, CNRS UPMC, Paris, France 3Centre de Geosciences/Mines-Paristech,´ Fontainebleau, France 4BRGM, Orleans,´ France 5CETP, Velizy,´ France 6CEMAGREF, Lyon, France 7LSCE, Gif-sur-Yvette, France Received: 4 September 2009 – Published in Hydrol. Earth Syst. Sci. Discuss.: 28 September 2009 Revised: 24 December 2009 – Accepted: 6 January 2010 – Published: 18 January 2010 Abstract. The Somme River Basin is located above a chalk the flooding of 2001 was characterized by an increase in the aquifer and the discharge of the somme River is highly in- quantity of the overflow and not much by a spreading of fluenced by groundwater inflow (90% of river discharge is the overflow areas. Inconsistencies between river discharge baseflow). In 2001, the Somme River Basin suffered from a and piezometric levels suggest that further investigation are major flood causing damages estimated to 100 million euro needed to estimate the relative influence of unsaturated and (Deneux and Martin, 2001). The purpose of the present re- saturated zones on the hydrodynamics of the Somme River search is to evaluate the ability of four hydrologic models Basin.
    [Show full text]
  • Trip Description a 2-Day Cycle Trip in the Heart of the Somme
    Trip description A 2-day cycle trip in the heart of the Somme bay Cycling holidays in the Somme bay visiting the beautiful villages, nice countryside and the birdpark of Marquenterre Destination France Location Baie de Somme Duration 2 days Difficulty Level Very easy Validity from march to november Minimum age 1 year Reference BS0201 Type of stay loop trip Itinerary Cycling the Somme Bay is the ideal activity for a short break in the countryside. Discover by bicycle this naturally protected bay located on the coast Cycling the Somme Bay is the ideal activity for a short break in the countryside. Discover by bicycle this naturally protected bay located on the coast of the English Channel where birds stop on their migratory course. Be enchanted by the diversity of landscapes, the sound of waves against the hull of the boats in the harbor of Saint-Valéry-sur-Somme and Le Crotoy and the song of the many birds that inhabit the bay. Admire them closely in the bird park Marquenterre in the company of ornithologists, who will tell you all about them. And do not forget your binoculars to observe the seal’s colony which rests on the sandbanks off Cap Hourdel. Day 1 Round trip from Saint- You can choose among different excursions around Saint-Valéry. You can go for the short Valéry option (26km) which takes you to the Cap Hourdel on a comfortable cycle path. After passing the lighthouse of Cap Hourdel, you keep on biking on the "white road", a wonderful cycle path along the sand dunes of the Channel before riding back towards Bike 26/38/49km Saint-Valéry.
    [Show full text]
  • Rapport EP Sentierlittoralawc.Pdf
    Préfecture de la Somme Projet de rétablissement dans sa continuité du sentier du littoral picard (section Quartier 08 au 26 juillet 2019 du « Bel Air » à Ault-Woignarue – Pointe du Hourdel à Cayeux-sur-Mer. SOMMAIRE : RAPPORT : 1) GENERALITES DE L’ENQUÊTE : Objet de l’enquête …………………………………………………………… page 1 1-1) Cadre juridique ……………………………………………………….. « 1-2) Identification du demandeur ………………………………………….... page 1 1-3) Contexte et caractéristiques du projet : ………………………………. « 2 1-3-1) Historique et contexte ……………………………………………… « 1-3-2) Implantation du projet …………………………………………………… page 3 1-3-3) Caractéristiques du projet ……………………………………………….. page 4 1-3-4) Description du projet ………………..……………………………… page 5 . 1-4) Composition du dossier …………………………………………........ page 8 2) DEROULEMENT DE L'ENQUÊTE 2-1) Désignation du commissaire enquêteur ………………………………....... page 9 2-2) Modalités de l’enquête …………………………………………………… « 2-3) Réunion préparatoire et …………… ………………………………………… « 2-4) Concertation préalable ……………………………………………………….. page 10 2-5) Information du public …………………………………………………………. « 2-6) Permanences et climat de l’enquête …………………………………………… page 11 2-7) Clôture de l’enquête ………………………………………………………….. « 2-8) Observations recueillies et courriers reçus …………………………………… page 12 à 13 2-9) Réponses du demandeur ……………………………………………………… « 2-9) Commentaires du commissaire enquêteur ……………………………………. « CONCLUSIONS ET AVIS DU COMMISSAIRE ENQUÊTEUR Préfecture de la Somme Projet de rétablissement dans sa continuité du sentier du littoral picard (section Quartier
    [Show full text]
  • The Allied Counter-Offensive in the Somme Sector
    USI Vol69 No2 Jun18_USI Vol55 No4/2005 31/05/2018 3:01 pm Page 14 CONTRIBUTED HISTORY PAPER The guns of August 1918: the Allied counter-offensive in the Somme Sector Marcus Fielding Royal United Services Institute of Victoria1 After absorbing and eventually halting the German spring offensive by July 1918, the Allies launched a major counter-offensive. On 8 August, 31 divisions – 6 British, 5 Australian, 4 Canadian and 16 French – and an American regiment, each supported by tanks, artillery and aircraft, began what would become series of attacks over several weeks in the Somme sector. Applying tactics that had been learned over years of war, they tore a great hole in the German lines and, by the end of August, had driven the German Army back to the Hindenburg Line – regaining most of the ground that had been lost to the Germans in their spring offensive. More significantly, the counter-offensive caused the German Army’s morale to collapse – an end to the war seemed near. Key words: Great War; World War I; 1918; Western Front; Allied offensive; Somme; Amiens; Albert; Bapaume; Montdidier; Noyon; Hindenburg Line. The German spring offensive, which began with free the railway lines that ran through Amiens from Operation Michael in March 1918, had culminated by the German shellfire. Foch agreed on a proposal by Field Second Battle of the Marne in mid-July 1918. By this Marshal Sir Douglas Haig, commander-in-chief of the time, the German superiority of numbers on the Western BEF, to strike on the River Somme east of Amiens with Front had sunk to a negligible lead which would be the objective of forcing the Germans away from the vital reversed as more American troops arrived.
    [Show full text]
  • À Vélo Entre Abbeville Et Saint-Valery-Sur-Somme Itinéraires Réservés À La Mobilité Douce : Les Eaux Sur 15Km
    Pour poursuivre Somme < Hauts de France < France La Baie de Somme, La Somme, un fleuve à partager vos Balades Le Conseil départemental, propriétaire du Canal de la un trésor naturel Profitez de votre étape en Baie de 2017 Somme de Péronne à Saint-Valery-sur-Somme, amé- Somme pour découvrir à pied, en Au Moyen Âge, la Somme se déplaçait nage le fleuve et sa vallée afin d’offrir aux habitants, dans la basse-vallée au gré des marées. pirogue, à cheval, ses multiples facettes Balades comme aux visiteurs, un espace de loisirs dans un Les navires marchands avaient parfois et trésors cachés, accompagné d’un - des difficultés à remonter jusqu’à cadre naturel privilégié. La véloroute Vallée de Somme, guide nature. Pour trouver ses coor Abbeville, alors 3ème port maritime de la répertoriée V 30 au schéma national des véloroutes et données, rendez-vous sur somme- en Vallée de Somme Manche. voies vertes, constitue un axe privilégié pour décou- tourisme.com ou sur vallee-somme.com Le canal maritime a donc été creusé vrir la Somme d’Est en Ouest, au fil de l’eau, et son La Véloroute Vallée de Somme vous pour faciliter la navigation. Il concentre patrimoine naturel et historique façonné par l’homme. permet également de rejoindre d’autres t - Imp. : CD80 textes / SL-IW à vélo entre Abbeville et Saint-Valery-sur-Somme itinéraires réservés à la mobilité douce : les eaux sur 15km. Des digues A la découverte des villes comme Péronne, Corbie, la Ronde de l’Eau, poumon vert au « renclôtures » ont aussi été construites Amiens ou Abbeville s’ajoute des traversées de petits cœur d’Abbeville, la Traverse du Pon- Distance 15 km afin de protéger les terres agricoles.
    [Show full text]
  • Le Crotoy / Cayeux-Sur-Mer La Vélomaritime - Eurovelo 4
    http:www.francevelotourisme.com 07/05/2021 Le Crotoy / Cayeux-sur-mer La Vélomaritime - EuroVelo 4 This stage of La Vélomaritime starts at Le Crotoy train station, then leads you to the port, with fabulous views of the Bay of the Somme. At Noyelles-sur-Mer, stop at the Chemin de Fer de la Baie de Somme train station to embark on an historic rail trip; not only does this give you a chance for a rest, it also allows you to cut out the stretch of track where you have otherwise to cycle beside the road up to Saint-Valery-sur-Somme. You then arrive at the heart of this port, with its fishermen’s homes below the medieval town. Continuing towards Le Hourdel, stop at the Maison de la Baie de Somme, covering the riches of the estuary. Then meander along La Route Blanche, set between the sea, coastal pebble banks and dunes. You may be lucky enough to spot seals before arriving at Cayeux- Départ Arrivée sur-Mer, a quintessential seaside resort. Le Crotoy Cayeux-sur-mer The route Durée Distance 1 h 55 min 28,76 Km From Le Crotoy to Noyelles-sur-Mer you follow a cycle track crossing a hunting domain, taking you up to the entrance to Saint-Valery-sur-Somme. For the safest Niveau Thématique option for families, we advise you to tackle the last I begin / Family Seaside portion of this stretch aboard the Chemin de Fer de la Baie de Somme’s historic train. Arriving at St Valery- sur-Somme, get off your bike to cross the bridge over the tourist train line.
    [Show full text]
  • Salt Marshes Expansion in the "Baie De Somme" Since the 17Th Century: Deciphering Natural Dynamics from Anthropic Disturbances
    Salt marshes expansion in the "Baie de Somme" since the 17th century: deciphering natural dynamics from anthropic disturbances Bruno Goffé, Dimitri Lague and Philippe Davy Chalk plateau N Abbeville Le Crotoy Le Hourdel Amiens Salt marshes Cayeux Noyelle St Valery sur mer Chalk plateau Abbeville 10 km High Tidal ranges 10 m Baie de Somme 11 m Mont St Michel With a dissymetric tidal flow : the outward flow having a lowest intensity than the inward one, Enhancing the sedimendation processes in bay with sand essentially coming from the Channel An apparent strong progression of salt marshes during the 20th century Active gravel bar Map of Polders (land claims) and Salt marshes progression from 1625 to 2010 1835 to 2010 East bay S. Marshes 1835 to 2010 South 1860 Seabank bay S. Marshes 1910 Railway Bank 1965 dyke 1625 to 1835 Seabanks and polders 1835 Somme Canal Polders and saltmarshes progression rates over 400 years moliere 1625 - 2010 Surfaces ha Total bay 4000,0 1910 (RW bank) 3500,0 1835 3000,0 dykes, East bay canal 2500,0 East bay bas champs 2000,0 Southfond bay de baie 1620 – 1835 South bay Seabanks total baie 1500,0 1000,0 500,0 (Dyke) 0,0 1965 1620 1670 1720 1770 1820 1870 1920 1970 2020 Dates Polders and saltmarshes progression rates over 400 years moliere 1625 - 2010 3000,0Surfaces ha East bay 2500,0 21 ha/yr from 1835 to 1920 progressivly decreasing 2000,0 from about 10 ha/y to 4 ha/yr from 1920 to present bastime. champs Total extension 2500 ha 1500,0 Southfond de baie bay 1000,0 3.5 ha/yr, total extension 1400 ha 500,0 0,0 1620 1670 1720 1770 1820 1870 1920 1970 2020 South Bay trend correspond to a natural steady-state salt marshes progression toward the noth controlled by the northward progression of the offshore gravel bar.
    [Show full text]