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The study of alluvial terraces helps in reconstructing the past geometries of rivers and makes it possible to assess the rate and pattern of fluvial incision and bedrock uplift. The fluctuations of river base levels are particularly variable and complex during the Late Quaternary in the lower course of rivers due to the interplay of responses to sea‐level fluctuations, tectonics and glacio‐isostasy. In this paper, the geometry...
Last Interglacial–Glacial sequence of palaeosols and calcareous slope deposits at Verteuil (Charente, southwest France)NARA Subscribed
The 12 m thick sequence of calcareous slope deposits and palaeosols exposed in a quarry at Verteuil (southwest France) has been studied and dated by optically stimulated luminescence. Emphasis was given to the identification and characterisation of palaeosols through geochemistry and micromorphology. The main clastic units, separated by major unconformities, were dated to MIS 6, MIS 5–4 and MIS 3–2. Stratified deposits (‘grèze...
Last Glacial Maximum active layer thickness in Western Europe, and the issue of ‘tundra gleys’ in loess sequencesNARA Subscribed
Late Marine Isotope Stage (MIS) 3 and MIS 2 loess–palaeosol sequences in Western Europe comprise alternating loess layer and 3‐ to 30‐cm‐thick bleached soil horizons with Fe–Mn oxide precipitations, which are usually interpreted as waterlogged active layers and referred to as ‘tundra gleys’. Active layer thickness data derived from a regional climate model simulation and the fossils (shells, earthworm granules) found in ‘tundr...
A map of Pleistocene aeolian deposits in Western Europe, with special emphasis on FranceNARA Subscribed
The Land Use and Cover Area frame Statistical survey (LUCAS) database on topsoil properties in Europe was used to map aeolian deposits. The points which satisfy the grain‐size criteria of coversands, loess and transitional facies were extracted from the rasters of predicted soil texture established by kriging of the LUCAS data by Ballabio et al . ( ). A comparison with already available maps, derived from a conventional field...
The lower terraces of the Dordogne River at Bergerac (south‐west France) were studied in detail using cores, trenches, ground penetrating radar profiles, and 14 C, optically stimulated luminescence and infrared stimulated luminescence dating. This study shows that the lowest terrace (Fx) is made up of two major lithostratigraphic units: (i) dominantly horizontal gravel strata interpreted as compound bar deposits in a braided r...
Archaeological investigations undertaken along a proposed highway together with the compilation of available geological and pedological data made it possible to give a first overview of the distribution of Pleistocene aeolian deposits in south‐west France. A chronological framework for deposition has been obtained using both radiocarbon ( n = 24) and luminescence ( n = 26) dating. It shows that aeolian transport was very activ...
New sections in the coversand of the Landes region, southwestern France, show at least two main depositional phases corresponding to the Upper Pleniglacial and the Lateglacial, which are separated by palaeosols. The lower palaeosol, a gleyic to histic cryosol overlying a net of sand wedges and dated to ca. 23 14 C ka BP, testifies to a short occurrence of permafrost. Impeded drainage due to the frozen subsoil is assumed to be...
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