The use of uplift modelling in the reconstruction of drainage development and landscape evolution in the repeatedly glaciated Trent catchment, English Midlands, UK

Abstract

Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. AbstractThe Trent Valley Palaeolithic Project has recently investigated the Quaternary evolution of the River Trent, the northernmost river system in western Europe with a documented long-timescale terrace staircase. The uppermost and lowermost reaches of the Trent, which drains the English Midlands, were glaciated during Marine oxygen Isotope Stage (MIS) 2, but older fluvial terraces dating back to MIS 8 are preserved in the remainder of the catchment, delineating the former course through the Lincoln Gap and across the Fen Basin (the modern course to the Humber estuary dating only from the latest Pleistocene). Numerical modelling enables lateral variations in uplift across the catchment to be deduced from differences in height of these fluvial terraces above the modern valley floor. Uplift rates thus indicated over the last two climate cycles attain values of 0.08 mm a 1 around Nottingham and Derby in the middle reach of the Trent, but are significantly lower elsewhere in the catchment; these variations are shown to relate to lateral variations in crustal properties, primarily variations in radioactive heat production in the underlying continental crust. Glaciation during the late Middle Pleistocene (MIS 8) caused significant changes to the Trent catchment, including the integration of the modern Upper Trent with the rest of the system. Older sedimentary evidence is much more fragmentary, but is used along with the results of the uplift modelling to reconstruct the earlier drainage. It is thus inferred that between the Anglian (MIS 12) and Wragby (MIS 8) glaciations the Trent already flowed into the Fen Basin via the Lincoln Gap, but the smaller-than-present catchment, indicated by gravel lithology, resulted in a much steeper longitudinal gradient, such that during interglacials (MIS 11 and 9) an elongated estuary would have developed, extending inland almost to the present location of Newark. Prior to the Anglian, much of the modern Trent catchment, including the rivers Derwent and Dove, drained into the former Bytham River. The modern Middle Trent catchment downstream of Nottingham was drained by a relatively small 'Ancaster Trent' river, which flowed above the Ancaster Gap; analysis of gravel lithology suggests that it probably joined the Bytham in the area that now forms the Fen Basin.

The Middle Pleistocene glacial evolution of northern East Anglia, UK: a dynamic tectonostratigraphic–parasequence approach

“…thinning) from the main Cromer Ridge forming phase (Lee et al ., ). However, an alternative scenario is that some or all of these lower‐elevation features may have formed during a younger pre‐Devensian glacial episode(s) (Lee et al ., ; Westaway et al ., ).…”

“…The number of Middle Pleistocene glaciations in East Anglia has also proven controversial. Suggestions of additional pre‐Anglian (Lee et al ., ) and post‐Anglian glaciations during various single (Baden‐Powell, ; Straw, , , , ; Lewis and Rose, ; Gibbard et al ., , 2012; Boreham et al ., ; Langford, ; Westaway et al ., ) or multiple glaciation models (Hamblin et al ., ; Rose, ) have been strongly debated. Further discussion of these chronological debates is beyond the scope of this paper and readers are directed to other papers that provide a commentary (Preece et al ., ; Rose, ; Lee et al ., ).…”

Isostatic compensation of Quaternary vertical crustal motions: coupling between uplift of Britain and subsidence beneath the North Sea

“…The various publications (e.g. those by Bridgland et al ., , 2015, and Westaway et al ., , on the River Trent) discuss the details of how, for each case study, the effects of such complexities can be analysed to quantify differences between fluvial incision and uplift. However, others (notably Gibbard and Lewin, , and Lewin and Gibbard, ) have argued that height differences between terraces of British rivers do not indicate uplift or, more specifically, that the processes involved are so complex that one has no way of knowing whether they do or not.…”

“…The terrace staircase of the principal river in central England, the Trent, is more difficult to interpret than its counterparts in southern England, because much of the catchment has been overridden by glaciations, including the recently identified Marine Isotope Stage (MIS) 8 Wragby Glaciation (e.g. Westaway, , White et al ., , , Bridgland et al ., , , Westaway et al ., ). By virtue of its principal tributary, the Derbyshire Derwent, which drains most of the Peak District uplands, the Trent catchment spans the transition between ‘lowland’ and ‘upland’ Britain, thus enabling comparison of the uplift histories indicated by the fluvial terraces in lowland parts of the catchment and by cave‐levels in the Carboniferous limestone in its upland part.…”

Examining the geometry, age and genesis of buried Quaternary valley systems in the Midland Valley of Scotland, UK

“…; Westaway et al . ), northern England (Boswell ; Howell ; Delaney ), south Wales (Al‐Saadi & Brooks ; Anderson & Owen ) and the North Sea (Bradwell et al . ; Stewart & Lonergan ; Stewart et al .…”