A morphological study of Durance River terraces from Tallard to Avignon, South-East France

Abstract

<jats:title>Abstract</jats:title><jats:p>This study of Durance River terrace morphologies in the lower 200 km of the valley shows that terrace ages, elevations and heights above the river generally all increase upstream. It is based on extensive fieldwork checked against geological maps and memoirs. Subdivision of the valley, based on gorges and former tectonic blockages, is relevant because there are no Durance terraces downstream of Mallemort and there are considerable differences between each reach. For most of the Pleistocene, the river was diverted through the Crau Plains to the sea. Below the Mirabeau gorge, there are a few narrow low and middle terraces. The best terrace development is between Mirabeau and the Sisteron defile. Upstream of that barrier there is glacial dominance. Changes in terrace continuity are illustrated by means of height-range diagrams and their rates of dissection have been quantified approximately, based on cosmic ray exposure age modelling. Climate forcing cannot explain all the changes found. The influence of tectonic activity was found to increase in an upstream direction and also with age on the southwestern flanks of the Alps.</jats:p>

Quaternary evolution of a large alluvial fan in a periglacial setting (Crau Plain, SE France) constrained by terrestrial cosmogenic nuclide (10Be)

“…The composition of the cobbles record a typical alpine petrographic spectrum, indicating that the plain was the former outlet of the paleo-Durance River, which now flows westward to the Rhône River along the north side of the Alpilles ridge ( Fig. 1; Roux, 1978, 1986;Warner, 2012). The northern alluvial sheet is the Arles terrace; the lateral equivalent of the local Valensole II Pliocene gravels (Clauzon, 1979) and is mainly composed of alpine Jurassic and Cretaceous limestone cobbles.…”

Application of Remote Sensing Methods to Study the Relief of Lowland River Valleys with a Complex Geological Structure—A Case Study of the Bug River

“…Therefore, these protrusions significantly affect the morphology of both the river channel itself (the thalweg path course) and the flow of flood waters on the floodplain surface (cf. e.g., [58][59][60]). During flood surges, the patency of the river channel is limited not only due to the low thickness of alluvial deposits and the resulting low possibilities of its deepening, but also due to the presence of stable islands that formed on hardly erodible sediments.…”