The Stratigraphic and Sedimentological Significance of Late Devensian Ice Sheet Surging in Holderness, Yorkshire, U.K
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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/229169941 The stratigraphic and sedimentological significance of Late Devensian Ice Sheet surging in Holderness, Yorkshire, U.K Article in Quaternary Science Reviews · December 1994 DOI: 10.1016/0277-3791(94)90102-3 CITATIONS READS 57 98 3 authors, including: David Bowen Cardiff University 75 PUBLICATIONS 2,260 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: Post-Cretaceous evolution of the British Isles View project All content following this page was uploaded by David Bowen on 31 July 2018. The user has requested enhancement of the downloaded file. Quaternary Science Reviews, Vol. 13, pp. 727-759, 1994. Pergamon Copyright © 1994 Elsevier Science Ltd. Printed in Great Britain. All rights reserved. 0277-3791/94 $26.00 0277-3791(94)00106-5 THE STRATIGRAPHIC AND SEDIMENTOLOGICAL SIGNIFICANCE OF LATE DEVENSIAN ICE SHEET SURGING IN HOLDERNESS, YORKSHIRE, U.K. N. EYLES,* A. M. MeCABE? and D.Q. BOWEN¢ *Glaciated Basin Research Group, Department of Geology, University of Toronto, Scarborough Campus, Scarborough, Ontario MIC 1A4, Canada tDepartment of Environmental Studies, University of Ulster, Coleraine, Co. Londonderry BT52 1SA, Northern Ireland, U.K. :~Department of Earth Sciences, University of Wales, Cardiff CF1 3YE, U.K. Abstract -- Amino acid analyses of marine mollusc valves show that the Basement Till of Q S R Holderness, Yorkshire, is of Late Devensian age (ca. 20,000 BP) and not pre-Ipswichian (> 125,000 BP) as is traditionally supposed. Together with the overlying Skipsea and Withernsea Tills the Basement Till is argued to be a 'deformation till' resulting from the repeated onshore surging of Late Devensian ice over a muddy sea floor, and the subglacial transport, attenuation and mixing of ~ ~,. marine sediment. Silts on the surface of the Basement Till, yielding '4C dates of 18,500 and 18,240 BP, have been regarded as minimum ages for Late Devensian glaciation in eastern England (e.g. \~..~,_ the Dimlington Stadial of Rose, 1985, 1989). The amino acid data presented here indicates that the maximum of the Late Devensian glaciation in eastern England occurred earlier. Sedimentological | ~ interpretation of the Late Devensian tills of Holderness as glacially-reworked marine sediments ~~ l,~ supports previous glacioiogical models of the British Ice Sheet involving surging of ice lobes along ~ I. '~ ~?.~ the coast of eastern England. The Basement, Skipsea and Withernsea tills are separated by shallow marine sediments and may be representative of 'deformable bed' till facies deposited below " ; Pleistocene ice sheets moving over soft, fine-grained sediments. • INTRODUCTION tidal facies. These may be correlated with fossiliferous beach gravels exposed beneath Withernsea till in the The objectives of this paper are to present descriptions western part of the area. of till facies and associated sediments exposed over some 70 km of the Holderness coastline of Yorkshire, U.K., and to interpret these data in the light of current knowl- PHYSICAL SETTING AND HISTORY OF edge of glacial depositional systems. New age estimates STRATIGRAPHIC INVESTIGATIONS for the oldest till are also presented. The Holderness area is of considerable importance because it contains a type The limit of Late Devensian ice along the eastern site, at Dimlington (Fig. 1), for Late Devensian glaciation coast of England is marked by a prominent moraine com- (Rose, 1985, 1989). At this location Skipsea and plex that records the onshore movement of a coastal ice Withernsea tills overlie organic silts that are '4C dated at lobe against the rising chalk upland of Flamborough 18,000 BP. The silts rest on the Basement Till which is Head and the Yorkshire Wolds. The complex extends regarded as belonging to a glaciation prior to the over 1200 km 2 of Holderness forming an arcuate belt of Ipswichian (last interglacial). The maximum of the Late drift up to 70 m thick from Flamborough Head in the Devensian glaciation is, therefore, regarded as post- north to the River Humber in the south (Fig. 2). Excellent dating 18,000 BP (Penny, 1969; Madgett and Catt, 1978; sections are provided through the complex along rapidly- Rose, 1985, 1989). New age estimates for the Basement eroding coastal cliffs and by gravel quarrying operations Till by amino acid epimerization suggests that the glacial inland. succession of Holderness is entirely Late Devensian. The Late Pleistocene glacial sediments of Holderness rest Basement and overlying till units appear to have been on a planated chalk surface that rises from 20-30 m deposited by surging ice lobes in the western part of the below sea level along the coast to a partly buried former North Sea Basin; till geometry, sedimentoiogy and struc- sea-cliff along the foot of the Yorkshire Wolds (Figs 2, ture indicate deposition by 'cannibalization' and rework- 3). The cliff line with buried marine beds at its base is ing of shallow marine deposits as the ice moved onshore exposed at Sewerby south of Flamborough Head (Figs 1, across a muddy embayment. Locally, the Skipsea and 4). Study of 70 km of rapidly eroding cliffs between Withernsea tills are separated by laminated, probably Dimlington and Flamborough has generated a large and 727 728 Quaternar 3" Science Reviews: Volume 13 contours in feet ~-~ S Brandesl~on 0 .or-~ "~ ~ "~ ~proatley UPONHULL • Burstwick ~so )Paull Bale ~ Keyingham • \ ~o~\~,~onHi¢~Land o . o ? ~ i mm Head FIG. 1. Topography of Holderness and adjacent areas with place names referred to in the text. N. Eyles et aL: Late Devensian Ice' Sheet Surging 729 Muston~ "'"~1 ~k,~ ~_ ~ Regional Ice Flows Sherburn • SI( .=ton Flamborough ~ Flamborough Head 120 • ~...~ Is&6~ Head Moraine "--"jl~'Lw. Sewe r by Gt. Driffield // kipsea Inland Limit of ~ / io • ~ ,.- ~ Morainic Topography !Hemph°lmet~Atwick - ~,~ -- °• ~~Hornsea ~ York and Escrick ~,~t Is~• erandesburton \ Moraines ~o• ~appleton , ~k = ~ Position of Buried ¢/ " t • ~&~Selby % • Beverley ~ . • Spot Heights in metres ~., 1110• • -- 0 • ~w • "~_~ooo,o ~:~ %-" ithernsea A-" 4 " imlington MOOR ,. Grimsb~y .o. Head oncaster °2 • ~" ~, ~, ? 15km Welton-Le-Wold FIG. 2. Postulated Late Devensian ice limits in Holderness and the Vale of York. (After Farrington and Mitchell, 1951; Valentin, 1957; Straw, 1961; Catt and Penney, 1966; Catt, 1987.) S Sewerby N /I I I I I ,,,,,.,., Flamborough Head ~ Beach Deposits o"~ v Skipsea v (aii ) rby v ~ ~ , ,t i I I I I ~"~% • ~" B r ,i I 1I, I I I l I ','*" f xQe F Beverley jJ~e i N Dimlington S • ,/,,~...~,e~x~. ' A Withernsea A-- O.D. • Basement • • isementTIH FIG. 3. Schematic representation of Late Devensian till stratigraphy in Holderness. Note the conflicting interpretations in the relative position of the 'Ipswichian Interglacial Beach' exposed at Sewerby. (a~) Catt and Penny, 1966. (a~) Lamplugh, 1890, this paper. 730 Quaternao' Science Reviews: Volume 13 SOUTH Figs 10-16 0 8 16 24 32 Figs 17, 18, 19 Figs 3, 7, 20 NORTH I I I 40 48 64 km ~ ~% ~ ¢=_.-, ;p... ~ .e '~o.'~ ~ "zo "o. q~ -~ -~,=. o, ¢,, '-".,,,, [~ Withersea Till ~ Silts, sands & ~ Skipseatill m Dimlington gravels silts Basement till Coarsening Stratified Buried cliff [~ inclusionsin [1~ beds ~ sequenceatUpward ~-~ Flamborou~h ~ Late glacial tills (Sewerby) Barmston Head moraine raised beach FiG. 4. North-south Late Devensian stratigraphy exposed along 70 km of Holderness coastline between Sewerby and Dimlington. Modified from Catt and Madgett (1981) and Lamplugh (1891 ). detailed literature on the glacial succession of Holderness (Bisat and Bell, 1941 ), are preserved within hollows on (see Catt and Penny. 1966; Catt, 1987, for references), the surface of the Basement till and are ~4C dated to Wood and Rome (1868) recognized a threefold glacial 18,500 ± 400 BP (I-3372) and 18,240 ± 250 BP (Birm- stratigraphy comprising Basement, Purple and Hessle 108) (Catt and Penny, 1966) indicating that the Skipsea 'boulder clays'. Bisat (1932. 1939, 1940, 1948) identified and Withernsea tills postdate ca. 18,000 BP. Wintle and four till sheets (Basement, Drab, Purple, Hessle) and Catt (1985) report a TL date of 17,500 _ 600 BP from introduced further subdivisions (e.g. upper and lower loess beneath Skipsea Till. Catt (1987) assigned the Purple) to account for differences in matrix texture, errat- Basement Till to a pre-lpswichian glacial event because ic composition and colour. In a significant paper, of its apparent truncation at Sewerby by a last interglacial Lamplugh (1911) identified sedimentological similarities (Ipswichian) raised beach (Catt and Penny, 1966, p. 384; between the Holderness succession and shelly shallow Catt, 1987; Fig. 3a~). Locally, the Basement Till includes marine sediments deformed and reworked at the base of a rafts of shelly, glauconitic sands (Bridlington Crag) surging glacier in Spitzbergen. Catt and Penny (1966), which contain dinoflagellates and derived pollen indica- Madgett and Catt (1978) and Catt (1987) revised earlier tive of a Pastonian age (> 1,600,000 BP; Reid and classifications and recognized three till units (Basement, Downie, 1973; Gibbard et al., 1991). The Skipsea Till Skipsea and Withernsea; Figs 3, 4, 5) characterized by truncates the Dimlington silts, underlies most of distinct mineralogical and erratic suites: the Hessle Till Holderness east of the Wolds and has been correlated was shown to be a postglacial weathered zone developed with tills in north Norfolk (Madgett and Catt, 1978; Catt, on both the Skipsea or Withernsea tills. The Basement Till 1987). The overlying Withernsea Till is less extensive was argued to be pre-Ipswichian in age and the Skipsea and extends about 10 km inland in eastern Holderness and Withernsea Tills to be Late Devensian (Fig. 3a0. where its surface is marked by hummocky topography The Dimlington Silts, which included moss remains (Figs 2. 3). Catt's (1987) depositional model for the Figs. 8,9 Figs. 4,6,10,-16 1 1 EAST WEST Morainic Topography ~Z metres p " 13 Beach Gravel Ice Contorted Gravels, ~ / ~ /N Shallow Water :~ t" Sands, Silts and Gravels _ ~ _ _ _ ~ ~ Skipsea Till ~ ~ 9 ~ Dimlington Silts 0 " Basement Till ~ 0 < 23km ~ ~.