Approche géotechnique du remplissage des « polémoformes » de la Grande Guerre

• Published in: Géomorphologie : relief, processus, environnement
• Main Authors: Devos, Alain, Laratte, Sébastien, Taborelli, Pierre, Ortonovi, Sarah, Fronteau, Gilles, Rabasté, Yoann, Duchêne, Bruno
• Other Authors: Groupe d'Étude sur les Géomatériaux et Environnements Naturels, Anthropiques et Archéologiques - EA 3795 (GEGENAA), Université de Reims Champagne-Ardenne (URCA)-SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS)-Maison des Sciences Humaines de Champagne-Ardenne (MSH-URCA), Université de Reims Champagne-Ardenne (URCA)-Université de Reims Champagne-Ardenne (URCA), Institut national de recherches archéologiques préventives (Inrap)
• Format: Article in Journal/Newspaper
• Language: French
• Published: HAL CCSD 2021
• Subjects: war landforms; WWI; archeological survey; penetrometry; bombturbation; Champagne area; « polémoformes »; Grande Guerre; fouille archéologique; pénétromètrie; Champagne; [SDE]Environmental Sciences; [SHS]Humanities and Social Sciences; Archeological Survey
• Online Access: https://hal.science/hal-03516565; https://doi.org/10.4000/geomorphologie.16212

International audience The World War I strongly marked the landscapes, especially on the western front, from Flanders to Alsace. The mine craters, shell craters, dugouts, trenches and communication trenches give off war landscapes characteristic of the front area. Theses geomorphic impacts subsist under forest cover, highlighted using the airborne LiDAR, while they are completely leveled in cultivated areas. In Champagne area, the archaeological survey linked to the urban extension of Rheims allows a better understanding of the spatial organization and the nature of the filling of these forms, by an archaeometric approach (dynamic penetrometry, mechanical oriented cross-sections, and UAV photography). Analysis conducted on an experimental area of 2 ha, in the first line of defense, makes it possible to characterize archaeological structures from the WW1 in a context of rendosols, developed on a stretched cryoclastic polygonal network, typical of the Champagne chalk surface. The results show that the forms of the WW1 are levelled by a multiphase fill with fine sedimentation synchronous with the conflict, followed by a poorly consolidated heterometric backfill. The latter coming from dismantled parados and parapet geomaterials, is rich in metallic fragments of accessory defense networks, and surmounted by an addition of topsoil. The bombturbation also determines a metallic contamination by "nugget effect" circumscribed in the shell crater, filled with earth fillings. These anthropogenic pedoturbations determine large spatial disparities in soil water reserves (crop marks) and are associated with geotechnical and pyrotechnic risks. La Grande Guerre a fortement marqué les paysages, notamment sur le front ouest, des Flandres à l’Alsace. Les cratères de mines, les trous d’obus, les abris, les tranchées et boyaux de communications dégagent des « polémopaysages » caractéristiques de la zone de front. Ces « polémoformes » subsistent sous couvert forestier et sont mises en évidence à l’aide du LiDAR aéroporté alors ...