River sedimentation and fluvial response to Holocene environmental change in the Yorkshire Ouse Basin, northern England

Abstract

Holocene alluvial sediment sequences and floodplain geomorphological histories from three valley-floor sequences in the Yorkshire Ouse Basin have been determined using a variety of field evidence and laboratory methods: geomorphological mapping, sediment coring and trenching, physical and chemical analysis of sedimentary units, and 14C dating. The application of multiple methods has revealed contrasting phases of river erosion, alluviation and depositional styles during the Late Quaternary at each of the individual study reaches. The gravel bedded River Swale at Catterick has been characterized by progressive valley-floor incision during the late Holocene with major phases of incision occurring during the cooler and wetter phase of the 'Little Ice Age’. Within the last c. 245 years, substantial thicknesses (up to 2 m) of overbank alluvium contaminated by metalliferous mining have been deposited across thefloodplain. In contrast, floodplain development in the lower reaches of the River Swale at Myton and the River Aire at Beal has predominantly been one of relative channel stability and vertical aggradation. Here, low floodplain gradients, wide valley floors, stable channels and limited lateral floodplain erosion have combined to produce thick (c.10 m) sequences of finegrained alluvium deposited in overbank environments. Mining-related contamination in lowland floodplains is much lower than at Catterick with limited amounts of historically contaminated alluvium being deposited across the floodplain. Although environmental change has been important in controlling Holocene floodplain development, the upper and lower reaches of the Yorkshire Ouse basin have responded differently to these effects because of reach-scale geomorphic controls. Caution needs to be applied before relating broad-scale environmental change to river response across a whole river basin.

Late Holocene development of a floodplain along a small meandering stream, northern Québec, Canada

“…Many Quaternary scientists used well dated alluvial sediments to reconstruct the geomorphological development of floodplains in relation with Holocene climate variability (Brown, 1987(Brown, , 1997Knox, 2000;Taylor et al, 2000), geoecological changes (Starkel, 1990) and modifications in the land-use (Brown, 1997). However, sites allowing to reconstruct the full extent of a floodplain development are rare because sedimentary evidences of past fluvial activity are often partly or entirely reworked, leading to an incomplete record of alluvial units (Lewin and Macklin, 2003).…”

Holocene alluvial sediment storage in a small river catchment in the loess area of central Belgium

“…In contrast, over long (centennial or millennial) timescales, estimation of eroded and deposited sediment volumes is difficult. Most studies of long-term sediment dynamics focus on the analysis of different types of sediment records, such as lake sediments (e.g., Zolitschka, 1998), alluvial sediments (e.g., Macklin et al, 1991;Lang and Nolte, 1999;Taylor et al, 2000;Grossman, 2001;Larue, 2002;Kukulak, 2003;Daniels and Knox, 2005), or colluvial deposits (e.g., Lang and Hönscheidt, 1999;Foster et al, 2000;Lang, 2003;Bertran, 2004). From these archives, periods with higher and lower sedimentation rates can be identified and linked to climate and land use changes.…”

Fluvial terrace formation in the northern Upper Rhine Graben during the last 20000 years as a result of allogenic controls and autogenic evolution

“…complex response of a fluvial system (Schumm, 1973(Schumm, , 1977Bull, 1991). This means that different river reaches may respond differently to the same instantaneous external forcing, depending on catchment and reach-specific characteristics (e.g., Mol et al, 2000;Taylor et al, 2000;Veldkamp and Tebbens, 2001; the threshold concept of Vandenberghe, 1995). As a result, complex response to an external factor varies spatially; implying correlation of fluvial units resulting from allogenic forcing across large river basins is often difficult or impossible.…”