Durham Research Online

Deposited in DRO: 19 May 2014 Version of attached le: Accepted Version Peer-review status of attached le: Peer-reviewed Citation for published item: Turner, A.J. and Woodward, J. and Stokes, C.R. and O'Cofaigh, C. and Dunning, S. (2014) 'Glacial geomorphology of the Great Glen region of .', Journal of maps., 10 (1). pp. 159-178. Further information on publisher's website: http://dx.doi.org/10.1080/17445647.2013.866369

Publisher's copyright statement: This is an Accepted Manuscript of an article published by Taylor Francis Group in Journal of Maps on 03/12/2013, available online at: http://www.tandfonline.com/10.1080/17445647.2013.866369.

Additional information:

Use policy

The 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.

Durham University Library, Stockton Road, Durham DH1 3LY, United Kingdom Tel : +44 (0)191 334 3042 | Fax : +44 (0)191 334 2971 https://dro.dur.ac.uk Journal of Maps

For Peer Review Only

A Glacial Geomorphological Map of the Great Glen Region of Scotland

Journal: Journal of Maps

Manuscript ID: TJOM-2013-0052

Manuscript Type: Original Article

Date Submitted by the Author: 20-May-2013

Complete List of Authors: Turner, Andrew; Northumbria University, Woodward, John; Northumbria University, Stokes, Chris; Durham University, Cofaigh, Colm; University of Durham, Geography Dunning, Stuart; Northumbria University,

Keywords: Great Glen, Geomorphology, British-Irish Ice Sheet, Deglaciation

URL: http://mc.manuscriptcentral.com/tjom Page 1 of 26 Journal of Maps

1 2 3 1 A Glacial Geomorphological Map of the Great Glen Region of Scotland 4 1, a 1 2 2 1 5 2 Andrew J. Turner , John Woodward , Chris R. Stokes , Colm Ó Cofaigh , Stuart Dunning

6 7 3 8 1 4 Faculty of Engineering and Environment, Department of Geography, Northumbria University, Ellison 9 10 5 Place, Newcastle-Upon-Tyne, NE1 8ST, UK 11 12 6 2 Department of Geography, Durham University, South Road, Durham, DH1 3LE, UK 13 14 7 a [email protected] Peer Review Only 15 16 8 17 9 Abstract 18 19 10 This paper presents a detailed glacial geomorphological map of the Great Glen region of 20 21 11 Scotland, UK, covering an area of over 6,800 km 2 extending from 56°34'7" to 57°41'1" N and from 22 23 12 3°44'2" to 5°33'24" W. This represents the first extensive mapping of the glacial geomorphology of the 24 25 13 Great Glen and builds upon previous studies that conducted localised field mapping or ice-sheet wide 26 27 14 mapping using remote sensing. Particular emphasis is placed on deriving medium-scale glacial 28 15 retreat patterns from these data, and examining differences in landsystem assemblages across the 29 30 16 region. Features were typically mapped at a scale of 1:8,000 to 1:10,000 and will be used to 31 32 17 investigate the pattern and dynamics of the British-Irish Ice Sheet during deglaciation. Mapping was 33 34 18 conducted using the NEXTMap digital terrain model. In total, 17,637 glacial landforms were mapped, 35 36 19 with 58% identified as moraines, 23% as meltwater channels, 10% as bedrock controlled glacial 37 38 20 lineations, 3% as eskers, 2% as cirques or arêtes, 2% as kame topography or kame terraces, and 1% 39 40 21 as drumlins. Additionally, ten palaeo-lake shorelines were identified. Complex landform assemblages 41 22 in the form of streamlined subglacial bedforms, moraines and glaciofluvial features exist across the 42 43 23 region. Extensive subglacial meltwater networks are found over the Monadhliath Mountain Range. 44 45 24 Transverse and longitudinal moraine ridges generally arc across valley floors or are located on valley 46 47 25 slopes respectively. Hummocky moraines are found almost exclusively across . Finally, 48 49 26 Eskers, meltwater channels and kame landforms form spatial relationships along the axis of 50 51 27 Strathspey. These glacial landsystems reveal the dynamics and patterns of retreat of the British-Irish 52 53 28 Ice Sheet during the last deglaciation. 54 29 55 56 30 Keywords: Great Glen, Geomorphology, British-Irish Ice Sheet, Deglaciation 57 58 59 60 1 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 2 of 26

1 2 3 31 1. Introduction 4 5 32 Glacial landforms are key ingredients for reconstructing the past extent and dynamics of the 6 7 33 former British-Irish Ice Sheet (BIIS), which extended across much of Britain and Ireland, and reached 8 34 the continental shelf edge during the last glaciation about 24,000 years ago (Bowen et al ., 2002; 9 10 35 Sejrup et al ., 2005; 2009; Bradwell et al. , 2008a; Chiverrell and Thomas, 2010; Clark et al ., 2012). In 11 12 36 Scotland, coastal and onshore geomorphology (e.g. Thorp, 1986; , 1989a, b; Merritt et al ., 1995; 13 14 37 Finlayson, 2006;For Finlayson Peer et al ., 2010) have Review been extensively employed Only to reconstruct flow paths 15 16 38 and retreat patterns. The limits of the Younger Dryas (YD) readvance (12.9-11.7 ka BP) are also well 17 18 39 known (e.g. Sissons, 1979a; Bennet and Boulton, 1993a; Clark et al ., 2004). Terrestrial evidence 19 20 40 suggests the configuration of the BIIS was complex and that the ice sheet was characterised by at 21 41 least four areas of major ice streaming located at the , The Minch, along the eastern coast 22 23 42 of England and within the Irish sea basin. These were zones of high flow velocity which drained large 24 25 43 volumes of ice from the ice sheet’s interior (e.g. Merritt et al., 1995; Bradwell et al ., 2008b; Hughes et 26 27 44 al ., 2010; Clark et al ., 2012). Less attention has been given to synthesising terrestrial limits and 28 29 45 medium-scale retreat patterns between offshore/coastal and YD ice margin positions. Whilst there are 30 31 46 a number of site specific studies of moraines, glaciofluvial landforms, and streamlined subglacial 32 47 bedforms in Scotland (e.g. McCann, 1966; Peacock, 1971; Young, 1978; Firth, 1989a; Golledge, 33 34 48 2006; Livingstone et al ., 2008), the glacial landforms across large sectors of the Scottish landscape 35 36 49 have yet to be systematically mapped . 37 38 50 In the Great Glen (GG) and surrounding region a paucity of detailed mapping has precluded an 39 40 51 accurate reconstruction of ice sheet retreat from the Scottish coast to the YD maximum extent 41 42 52 positions mapped by Clark et al ., 2004. However, recent research in the Monadhliath Mountain Range 43 44 53 has suggested that ice cover between ~15 ka BP and 11.7 ka BP was more extensive than previously 45 54 thought (Boston et al ., 2013). 46 47 55 The accompanying geomorphological map covers a region of 6,828 km 2 centred on the Great 48 49 56 Glen in Scotland. This builds upon previous mapping efforts (e.g. Clark et al ., 2004; Hughes et al ., 50 51 57 2010) and is part of ongoing research into the nature of deglaciation through the Great Glen sector of 52 53 58 the BIIS including subaqueous geophysical surveys of the lochs in the region (e.g. Turner et al. , 2012; 54 55 59 2013a, b). 56 57 60 58 59 60 2 URL: http://mc.manuscriptcentral.com/tjom Page 3 of 26 Journal of Maps

1 2 3 61 2. Methods 4 5 62 2.1 Data Sources 6 7 63 The geomorphological map of the Great Glen region has been produced from high-resolution 8 64 Intermap Technologies NEXTMap digital terrain data which has a horizontal resolution of 5 m and 9 10 65 vertical resolution of 1 m. ESRI ArcGIS 9.3 software was used during mapping procedures. An 11 12 66 orthogonally illuminated hillshade of the study area was produced (Smith and Clark, 2005). As 13 14 67 lineations onFor the land surfacePeer have a predominant Review south-west/north-east Only trend, the digital elevation 15 o 16 68 model was initially shaded from an azimuth perpendicular to their orientation (north-west: 315 ). To 17 18 69 reduce the bias associated with hillshading from a single solar azimuth, a second relief map was

19 o 20 70 produced with a perpendicular north-east (45 ) azimuth (e.g. Smith and Clark, 2005). A solar elevation 21 o 71 angle of 45 was selected for these images to reveal subtle topography within the study area. To 22 23 72 further reduce azimuth biasing, a shaded relief image with an illumination angle of 90 o (vertical) was 24 25 73 also produced, as suggested by Smith and Clark, (2005). 26 27 74 Additional contextual data from Ordnance Survey MasterMap, available from the Edina 28 29 75 ShareGeo website (http://edina.ac.uk/projects/sharegeo/index.shtml), at a scale of 1:2,000 were also 30 31 76 used. These data allowed roads, buildings, managed woodland, railway lines, rivers/streams, tree 32 77 cover and landforms pertinent to this study to be identified. A base map for the remainder of Scotland 33 34 78 is provided by NASA Shuttle Radar Topography Mission (SRTM) data, available at 35 36 79 http://www2.jpl.nasa.gov/srtm/. This layer is not used in mapping procedures due to its low resolution 37 38 80 (90 m - Farr et al ., 2007) and vertical elevation errors (5 m - Rodriguez et al ., 2005). All map layers 39 40 81 were displayed using the British National Grid (OSGB 1936 datum) and projected to the Transverse 41 42 82 Mercator, airy spheroid. 43 44 83 45 84 2.2 Mapping Procedure 46 47 85 The glacial geomorphological map was generated by visually identifying features of glacial 48 49 86 origin from the relief shaded images described above. Across the area 17,637 individual glacial 50 51 87 features were systematically located and classified according to common morphological descriptions 52 53 88 (see section 3). Landforms were digitised within ArcGIS 9.3 software as colour coded polyline data at 54 55 89 a scale of between 1:8,000 and 1:10,000. In cases where a landform was tentatively identified in the 56 57 90 imagery, but lacked pronounced relief or was otherwise difficult to see, ESRI ArcScene 9.3 3D 58 59 60 3 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 4 of 26

1 2 3 91 visualisation software was used to aid in scrutinising landforms. This helped classify the exact feature 4 5 92 type, or allowed a feature to be rejected as unimportant to the study (e.g. roads, electrical pylons, 6 7 93 buildings). 8 94 Whilst previous mapping has identified a wealth of glacial landforms such as bedrock controlled 9 10 95 glacial features (e.g. Peacock et al ., 1992; Hughes et al ., 2010), drumlins (Hughes et al ., 2010) 11 12 96 meltwater channels (e.g. Gordon, 1993; Greenwood et al ., 2007; Margold and Jansson, 2012), eskers 13 14 97 (e.g. Young,For 1978; Key, 1997),Peer kame features Review (e.g. Young, 1978; May Only and Highton, 1998; Russell 15 16 98 and Marren, 1998), moraines (e.g. Bennett and Boulton, 1993a, b; Benn and Lukas, 2006; Dunlop 17 18 99 and Clark, 2006a, b; Smith et al., 2006) and ice dammed palaeo-lake shorelines (e.g. Sissons, 1977b; 19 20 100 1979a, c; Palmer et al ., 2010); a new map was required that covers a regional area and synthesises 21 101 these data at the medium-scale. The descriptions of landforms given in the above references have 22 23 102 also provided criteria for identification of previously unmapped glacial landforms in the region. Where 24 25 103 a landform was confirmed from visual identification of the relief imagery they were included on the 26 27 104 final geomorphological map. The source references for such features were added to the attribute 28 29 105 table entry during mapping. It is estimated that 80% of the landform record presented in the glacial 30 31 106 geomorphological map has not been identified previously. 32 107 All features were further subdivided into 3 ‘certainty categories’ (cf. Greenwood, 2007). 33 34 108 Category 1 (‘definite’) denotes a given landform possesses most of the characteristic attributes 35 36 109 described in the literature for that landform type. Category 2 (‘probable’) refers to those landforms 37 38 110 which are most likely of a particular feature type but some uncertainty remains as not all classic 39 40 111 characteristics may be present. The final category 3 (‘possible’) landforms display only a few of the 41 42 112 typical characteristics of its type or, alternatively, possess characteristics of two or more landform 43 44 113 types and could potentially be misidentified. Category 3 landforms are omitted from the final 45 114 geomorphological map. Statistical information for each landform type was drawn from examples 46 47 115 classified as ‘definite’ or ‘probable’ (Table 1). 48 49 116 A short ground truthing field excursion was also conducted to verify several landform types. 50 51 117 Locations included the northern and southern shores of , several locations within the 52 53 118 Monadhliath Mountain Range and Glen Roy. 54 55 119 The palaeo-shorelines of ice dammed lakes, which previously occupied glens, were produced 56 57 120 by first identifying the palaeo-shoreline from the hillshaded NEXTMap data based on descriptions by 58 59 60 4 URL: http://mc.manuscriptcentral.com/tjom Page 5 of 26 Journal of Maps

1 2 3 121 Sissons (1977b; 1979a, c) and Palmer et al . (2010). Where the surface elevation of a palaeo- 4 5 122 shoreline was known, an isoline of the appropriate elevation above sea-level was generated in the 6 7 123 GIS using a geoprocessing tool in order to keep elevation error to a minimum. The extent of the 8 124 resulting palaeo-lake was therefore delineated primarily by topography, but also from associated 9 10 125 moraine limits. A caveat to this is that the NEXTMap digital elevation model retains all natural and 11 12 126 anthropogenic features in addition to the relief of the land surface; therefore where the lake shores 13 14 127 disappear underFor tree cover, Peer the mapping algorithmReview would map tree elevation Only instead of palaeo- 15 16 128 shoreline elevation. Forested areas are therefore omitted from the elevation analysis. Glacio-isostatic 17 18 129 adjustment is not accounted for, but given the relatively small size of the lakes, this is unlikely to be a 19 20 130 problem. 21 131 22 23 132 3. Glacial Geomorphology 24 25 133 3.1 Cirques/Arêtes 26 27 134 Cirques are erosional hollows in mountainous terrain with concave slopes bounded upstream 28 29 135 by a sharp arcuate headwall and sharp valley side ridges (arêtes) (Gordon, 2001; Evans, 2006) and 30 31 136 are flat floored and open at the downstream end (Evans and Cox, 1974; Benn and Evans, 2010) (Fig. 32 137 2a, b). In the Great Glen region, clusters of cirques exist in the vicinities of Loch Ericht, Ben Nevis 33 34 138 Mountain Range, , Loch Loyne and Loch Affric (Fig. 1). These locations lie within YD ice 35 36 139 cap limits as defined by Clark et al . (2004). Three clusters of cirques occur outside the YD limit in 37 38 140 proximity to Loch Laggan, Strathossian and Strathconnon (Fig. 1). It should be noted that the YD ice 39 40 141 limits presented here are based on Clark et al . (2004). However, recent work in the Monadhliath 41 42 142 Mountain Range suggests a more extensive ice limit during the YD cold event (Boston et al ., 2013). 43 44 143 45 144 3.2 Streamlined bedrock 46 47 145 Streamlined bedrock features are highly elongate, (e.g. Table 1) ice flow parallel landforms 48 49 146 (Bradwell et al ., 2008b), possessing sharp crest lines in cross-profile and gentle long-profile 50 51 147 morphology (Jansson et al ., 2003). The highest concentration occurs over the mountainous areas 52 53 148 surrounding Loch Ness (e.g. Fig. 2c, d); other concentrations are located on the western side of 54 55 149 Strathspey and on peaks overlooking Glens Moriston, Roy and Spean. These fields of streamline 56 57 58 59 60 5 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 6 of 26

1 2 3 150 bedrock ridges predominantly occur outside the YD ice limit. Within the YD limit, the streamlined 4 5 151 features are located in the vicinities of Lochs Aber, Affric, Garry, Loyne (Fig. 1). 6 7 152 8 153 3.3 Crags and Tails 9 10 154 Crags and tails are ice moulded bedrock outcrops with indistinct or sharp crests and a leeward 11 12 155 tail/ridge of unlithified material (usually till) tapering in the direction of ice flow (Smith et al ., 2006; 13 14 156 GreenwoodFor and Clark, 2008;Peer Hughes et al .,Review 2010) (Fig. 2c, d). They areOnly have a relatively high 15 16 157 elongation ratio (Table 1) and are found outside the YD ice limits over elevated terrain, and surround 17 18 158 the northern portion of Loch Ness. Other fields are found in proximity to , Strathconnon, the 19 20 159 Clava river valley, and on peaks overlooking Strathspey (Fig. 1). Additionally, the northern Affric/Ness 21 160 clusters surround the peripheries of drumlin fields discussed below. 22 23 161 24 25 162 3.4 Drumlins 26 27 163 Drumlins are streamlined, commonly described as asymmetric, ovoid hills aligned parallel to ice 28 29 164 flow with gentle stoss and lee slopes which may also be spindle-like, parabolic or barchanoid in 30 31 165 planview (Mitchell and Riley, 2006; Smith et al ., 2006; Greenwood and Clark, 2008; Hughes et al ., 32 166 2010). In this region, they are more elongate when compared to other types of glacial lineations 33 34 167 (Table 1). They encircle the northern and eastern shores of Loch Ness, and they surround the 35 36 168 northern and southern shorelines of Beauly Firth and west of Cromarty Firth. 37 38 169 39 40 170 3.5 Transverse moraines 41 42 171 Transverse moraines are ridges deposited perpendicular to ice flow which may be single ridges 43 44 172 or broken into linear chains arcing across valley floors (Sissons, 1979c, Benn and Lukas, 2006; 45 173 Golledge, 2006; Smith et al ., 2006). The mean length of transverse moraines has been calculated to 46 47 174 be ~128 m (Table 1). A characteristic cluster has been identified at the Blackwater Reservoir (Fig. 3a, 48 49 175 b). Other fields occur in glens adjacent to Lochs Arkaig, Cluanie, Eil and Quioch with two further 50 51 176 clusters located in Glen Spean and north-east of Loch Ness (Fig. 1). 52 53 177 54 55 178 3.6 Longitudinal (ice flow parallel) moraines 56 57 58 59 60 6 URL: http://mc.manuscriptcentral.com/tjom Page 7 of 26 Journal of Maps

1 2 3 179 Longitudinal moraines occur laterally on valley slopes (lateral moraines) (Sissons, 1979c), on 4 5 180 valley floors running parallel to the valley long axis and former ice flow (Benn and Evans, 2010), or 6 7 181 extend from central ridges at the confluence of adjacent valleys, showing where two separate glacier 8 182 systems have merged into one coherent ice mass flowing down-valley (medial moraines) (e.g. 9 10 183 Spagnolo and Clark, 2009). They are frequently asymmetrically distributed across opposing valley 11 12 184 slopes (Sissons, 1979c). They have also been calculated to possess a slightly longer mean length 13 14 185 than transverseFor moraines, Peer measured at ~149 Review m (Table 1). A large population Only is found at the northern 15 16 186 end of Loch Ness and close to Foyers, with examples found at the YD limit in Glen Moriston. Further 17 18 187 fields are found in proximity to Lochs Arkaig and Ossian, and across Rannoch Moor (Fig. 1). 19 20 188 21 189 3.7 Ribbed moraine 22 23 190 Ribbed moraine consist of curved, closely spaced ridges aligned transverse to ice flow with a 24 25 191 characteristic anastomosing pattern or ‘ribbing’ (Lundqvist, 1989; Aylsworth and Shilts, 1989; 26 27 192 Hättestrand and Kleman, 1999; Dunlop and Clark, 2006a, b) (Fig. 3e, f). They may have multiple sub- 28 29 193 crests or singular flat apexes (Dunlop and Clark, 2006a, b; Hughes et al ., 2010). Ribbed moraines are 30 31 194 exclusively found surrounding the southern tip of the Cromarty Firth, deposited above a 40 m palaeo- 32 195 sea level shoreline mapped by Firth (1989a) with few examples below this (Fig. 3e, f). They also 33 34 196 possess the greatest mean length (measured perpendicular to ice flow direction), at ~243 m (Table 1). 35 36 197 37 38 198 3.8 Hummocky terrain 39 40 199 Hummocky terrain is defined as irregular mounded topography which exhibits varying degrees 41 42 200 of order; ranging from unordered (chaotic) assemblages to suites of nested linear elements (Sissons, 43 44 201 1976; Smith et al ., 2006). Hummocky terrain commonly occurs in localised depocentres in the form of 45 202 broad and low ridges in the landscape, which may grade into till sheets (Key, 1997). The largest 46 47 203 population was observed in the Rannoch Moor area with other concentrations located in western 48 49 204 Strathspey, in the vicinities of Lochs Lochy, Eil and Quioch, and west of the YD ice limit in Glen Affric 50 51 205 (Fig. 1). 52 53 206 54 55 207 3.9 Kame topography 56 57 58 59 60 7 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 8 of 26

1 2 3 208 Kame and kettle topography are assemblages of mounds and hollows generated through 4 5 209 supraglacial or ice contact glaciofluvial deposition which may also represent zones of in situ ice 6 7 210 stagnation, wastage, ice-block meltout or jökulhlaups (Sissons, 1976; 1979c; Young, 1978; Russell 8 211 and Marren, 1998; Fay, 2002; Gordon and McEwen, 1993) (Fig. 4a, b). The largest field is located on 9 10 212 the western slopes of Strathspey with another series of features found at the Auchteraw Terrace, 11 12 213 close to (Fig. 1). Another field exists at the head of Loch Treig (Fig. 1). 13 14 214 For Peer Review Only 15 16 215 3.10 Kame terraces 17 18 216 Kame terraces are gently sloping depositional benches perched on valley sides, and are 19 20 217 related to the lateral deposition of glaciofluvial outwash (Evans, 2005); or possibly outwash deposition 21 218 in ice marginal ribbon lakes (Benn and Evans, 2010). They often occur in series and have differing 22 23 219 gradients relating to former ice margin morphology (Fletcher et al. , 1996; Benn and Evans, 2010). The 24 25 220 largest concentration occurs in Glen Moriston on the slopes on either side of the modern river within 26 27 221 the YD ice limit. Also within the ice limit, kame terrace fragments are identified north of Loch Treig 28 29 222 (Sissons, 1979c) (Fig. 1). Outside of the YD limit, in Strathspey, terrace fragments are observed north 30 31 223 of Newtonmore (Young, 1978) and in the northern Findhorn river valley (Fletcher et al. , 1996). 32 224 33 34 225 3.11 Lateral meltwater channels 35 36 226 Lateral meltwater channels develop parallel to ice margin surfaces and erode distinct lateral or 37 38 227 arcuate ‘grooves’ or benches into the topography during deglaciation (Dyke et al ., 1992; Kleman et 39 40 228 al ., 1992; Dyke, 1993; Hättestrand, 1998; Hättestrand and Stroeven, 2002; Sollid and Sørbel, 1994; 41 42 229 Smith et al ., 2006; Greenwood et al ., 2007). Outside the YD ice limit, channels are located at the 43 44 230 peripheries of Loch Ness and valleys in the Monadhliath Mountain Range (Fig. 1). Within the ice limit, 45 231 concentrations are found at Lochs Arkaig, Laggan and Ossian, and surround Leum Uilleim (Fig. 4e, f). 46 47 232 Statistical information obtained from all meltwater channel types are presented in Table 1. 48 49 233 50 51 234 3.12 Sublateral meltwater channels 52 53 235 Sublateral channels typically have greater angles of dip on the land surface than lateral 54 55 236 examples and often occur in series at elevations below major longitudinal moraine ridges and in some 56 57 237 instances plunge through down slope chutes or fissures (Sissons, 1967; Greenwood et al ., 2007). 58 59 60 8 URL: http://mc.manuscriptcentral.com/tjom Page 9 of 26 Journal of Maps

1 2 3 238 Concentrations exist in Glen Moriston, over Leum Uilleim, and at Urquhart Bay and Foyers, Loch 4 5 239 Ness (Fig. 1). 6 7 240 8 241 3.13 Subglacial meltwater channels 9 10 242 Subglacial channels can form in an upslope flow direction and may overtop mountainous 11 12 243 peaks/ridges and erode directly into bedrock, due to controls imparted by ice flow direction and 13 14 244 hydrostatic Forpressures (Sissons, Peer 1967; Nye, Review 1973; Young, 1978; Sharpe Only and Shaw, 1989; Sugden et 15 16 245 al ., 1991; Kleman and Borgström, 1996; Kleman et al ., 1997; Hättestrand and Stroeven, 2002). They 17 18 246 may also preferentially erode into faults in bedrock surfaces and display anastomosing or braided 19 20 247 patterns (Margold and Jansson, 2012). The highest density is found over the Monadhliath Mountain 21 248 Range and on the elevated terrain between Loch Ness and Glen Affric (Fig. 1). These areas are 22 23 249 located outside of the YD ice limit. Within the ice limit small clusters are located on the flanks of Leum 24 25 250 Uilleim, Loch Treig and Loch Eil (Fig. 1). 26 27 251 28 29 252 3.14 Proglacial meltwater channels 30 31 253 Proglacial channels are formed at the termini of glaciers and ice sheets which can form braided 32 254 and branching channel networks in the proglacial zone (Benn and Evans, 2010). They often rapidly 33 34 255 erode pre-existing channels or down-cut into bedrock surfaces and may be difficult to distinguish from 35 36 256 modern drainage channels, or, if channels are of low relief, they may have a very weak signature on 37 38 257 the land surface (Benn and Evans, 2010; Margold et al ., 2011). Only three features have been 39 40 258 confirmed as proglacial channels. These are located in the Glen Roy area, eroded through a series of 41 42 259 transverse moraines and into the top of a proglacial fan complex known as the Glen Turret Fan (Chen 43 44 260 and Rose, 2008). 45 261 46 47 262 3.15 Over-col spillway channels 48 49 263 Over-col spillways (Fig. 4f) are deep channels or gorges incised into bedrock which are often 50 51 264 found in association with former ice dammed lakes (Margold and Jansson, 2012). Four of the 52 53 265 spillways are associated with the former ice dammed lakes in Glens Spean, Roy and Gloy, with 54 55 266 further spillways located near Beinn a'Bha'ach Ard and Sgurr na Ruaidhe between Strathconnon and 56 57 267 Strathfarrar and at Leum Uilleim (Fig. 1). 58 59 60 9 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 10 of 26

1 2 3 268 4 5 269 3.16 Eskers 6 7 270 Eskers are well-defined, sub-linear to sinuous ridges which may have smooth or sharp crests 8 271 and are often associated with lakes, kame and kettle topography. They typically trend in the direction 9 10 272 of former meltwater flow which may not necessarily be the same as the regional ice flow direction 11 12 273 (Smith et al ., 2006; Margold and Jansson, 2012). They can form supraglacially, englacially or 13 14 274 subglaciallyFor (Banerjee and Peer McDonald, 1975) Review via sustained deposition Onlyover long timescales or via 15 16 275 single high-magnitude events (jökulhlaups) (Burke et al ., 2008; 2010). Eskers are observed in 17 18 276 proximity to Glens Moriston and Spean, Strathossian, and on slopes overlooking Lochs Ericht, Lochy, 19 20 277 Oich, and Treig. Elsewhere, eskers are found in the vicinities of Strathspey, Loch Laggan and the 21 278 Clava and Findhorn river valleys. A small number of eskers located at the northern end of Loch Ness 22 23 279 are larger in scale. 24 25 280 26 27 281 3.17 Paleo-lake shorelines 28 29 282 Palaeo-lake shorelines are laterally continuous valley side terraces, notches or benches that 30 31 283 are the result of wave erosion and beach deposition at a former long-lived palaeo-water-level which 32 284 also often occur in series (Darwin, 1839; Sissons, 1977a; 1978; Sissons and Cornish, 1982; Chen 33 34 285 and Rose, 2008; Margold and Jansson, 2012). Six shorelines are identified in Glen Doe at 510 m, 406 35 36 286 m, 359 m, 334 m, 324 m and 305 m above sea-level (a.s.l.) (Fig. 5a-f). A 355 m a.s.l. shoreline is 37 38 287 identified in Glen Gloy and crosses two sets of transverse moraine deposited within the valley bottom, 39 40 288 resulting in possible minimum and maximum extents (Fig. 5g, h). Three are traced in Glen Roy where 41 42 289 they are laterally extensive and occur at 350 m, 325 m and 260 m a.s.l. (Fig. 5i-k). The 260 m a.s.l. 43 44 290 shoreline is also traced in Glen Spean (Fig. 5j, k). 45 291 46 47 292 4. Conclusions 48 49 293 The map accompanying this article is the first detailed map of the glacial geomorphology of the 50 51 294 Great Glen region of Scotland. This map builds upon and extends previous work by both field 52 53 295 researchers, cartographers and the BRITICE data set by synthesising small-scale mapping efforts at 54 55 296 the medium-scale, including previously unmapped landform assemblages, to produce a detailed 56 57 297 regional pattern of glacial landforms which can be used to reconstruct the dynamics and retreat 58 59 60 10 URL: http://mc.manuscriptcentral.com/tjom Page 11 of 26 Journal of Maps

1 2 3 298 patterns of the former BIIS in this sector of Scotland. Complex landform assemblages exist across the 4 5 299 study area especially on the eastern side of the Great Glen, where a larger number of landforms

6 2 7 300 appear to have been preserved. In total 17,637 individual features were mapped in the 6828 km 8 301 study area; 58% of these are moraine, 23% are meltwater channels, 10% are bedrock lineations, 3% 9 10 302 are eskers, 2% are cirques or arêtes, 2% are kame and kettles or kame terraces and 1% are 11 12 303 drumlins. 13 14 304 WhereFor mountainous Peer areas are present, Review glacial erosion has produced Only cirques, marking initial 15 16 305 accumulation areas and final deglacial enclaves of the former ice cover in Scotland. Over elevated 17 18 306 ground, streamlined bedforms dominate, with drumlins occupying lower ground to the north-east. 19 20 307 Extensive subglacial meltwater networks are found over the Monadhliath Mountain Range. Across low 21 308 elevation terrain in the southern extremity of the study area, in western Rannoch Moor, moraine 22 23 309 ridges are the prevailing landforms. Transverse and longitudinal moraine ridges are generally located 24 25 310 across valley floors or deposited on valley slopes respectively dispersed across the study area. 26 27 311 Longitudinal moraines additionally share a spatial relationship with lateral meltwater channels along 28 29 312 the axis of the Great Glen. Eskers, meltwater channels and kame landforms also form spatial 30 31 313 relationships along the axis of Strathspey. 32 314 The glacial geomorphological map accompanying this paper synthesises morphological data in 33 34 315 order to examine the nature of glaciation in the Great Glen region and the potential evidence of fast 35 36 316 flow (ice streaming). Particular emphasis is placed on deriving regional glacial retreat patterns, and 37 38 317 finally, examining any differences in morphology or landsystem assemblages occurring within the 39 40 318 Younger Dryas ice cap limits. 41 42 319 43 44 320 5. Software 45 321 Relief shaded visualisations of the NEXTMap dataset and onscreen digitisation of landforms 46 47 322 were done using ESRI ArcGIS 9.3 software. The 3D visualisation tool of ArcScene 9.3 was used to 48 49 323 aid assessment of landform features where this was difficult in the planview of ArcGIS 9.3. The final 50 51 324 geomorphological map was produced in ArcGIS 9.3 and exported as a PDF document. 52 53 325 54 55 326 6. Acknowledgements 56 57 58 59 60 11 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 12 of 26

1 2 3 327 The authors would like to thank Dr. Ian S. Evans of Durham University in helping to find the 4 5 328 relevant BGS map sheets for the study area (BGS, 1995; 1997; 2000). We would also like to thank 6 7 329 Dr. Mike Lim of Northumbria University for providing Intermap Technologies NEXTMap data for the 8 330 study area and Dr. Clare M. Boston of Exeter University for fruitful discussions on the landforms of the 9 10 331 Monadhliath Mountain Range. 11 12 332 13 14 333 7. Map DesignFor Peer Review Only 15 16 334 All glacial landforms were mapped as a series of polyline data, colour coded to feature type for 17 18 335 expedient mapping. For meltwater channels, kame features and moraines different colours were also 19 20 336 used to differentiate between sub-types (e.g. dark blue for subglacial meltwater channels and lighter 21 337 blues for lateral and sublateral types). Mapped landforms were overlaid on various hillshaded 22 23 338 renditions of the NEXTMap data and coloured white to emphasise the topography of the area and to 24 25 339 aid clarity of individual features. Place names were kept to an absolute minimum on the final 26 27 340 geomorphological map to avoid cluttering the map and obscuring geomorphological features. This 28 29 341 accompanying paper contains a figure with all relevant place names mentioned in the text. 30 31 342 32 343 8. References 33 34 344 AYLSWORTH, J. & SHILTS, W. (1989), 'Bedforms of the Keewatin Ice Sheet, Canada.', Sedimentary 35 36 345 Geology 62 , 407-428. 37 38 346 BANERJEE, I. & MCDONALD, B. (1975), Nature of Esker Sedimentation, In: JOPLING, A. & 39 40 347 MCDONALD, B., ed., Glaciofluvial and Glacio-lacustrine Sedimentation, Special Publication 23 , 41 42 348 Society of Economic Palaeontologists and Mineralogists, pp. 132-154. 43 44 349 BENETTI, S., DUNLOP, P. & Ó COFAIGH, C. (2010), 'Glacial and glacially-related features on the 45 350 continental margin of northwest Ireland mapped from marine geophysical data', Journal of 46 47 351 Maps v2010 , 14-29. 48 49 352 BENN, D. & EVANS, D. (2010), Glaciers and Glaciation (2nd Edition) , Hodder, London. 50 51 353 BENN, D. & LUKAS, S. (2006), 'Younger Dryas glacial landsystems in North West Scotland: an 52 53 354 assessment of modern analogues and palaeoclimatic implications', Quaternary Science 54 55 355 Reviews 25 , 2390-2408. 56 57 356 BENNETT, M. & BOULTON, G. (1993a), 'Deglaciation of the Younger Dryas or Loch Lomond Stadial 58 59 60 12 URL: http://mc.manuscriptcentral.com/tjom Page 13 of 26 Journal of Maps

1 2 3 357 icefield in the northern Highlands, Scotland', Journal of Quaternary Science 8, 133-145. 4 5 358 BENNETT, M. & BOULTON, G. (1993b), 'A reinterpretation of Scottish ' hummocky moraine' and its 6 7 359 significance for the deglaciation of the during the Younger Dryas or Loch 8 360 Lomond Stadial', Geological Magazine 130 , 301-318. 9 10 361 BOSTON, C.M., LUKAS, S., MERRITT, J.W. (eds.) (2013). The Quaternary of the Monadhliath 11 12 362 Mountains and Great Glen, Field Guide . Quaternary Research Association, London. 13 14 363 BOWEN, D.,For PHILLIPS, F.,Peer MCCABE, A., KNUTZ,Review P. & SYKES, G. (2002),Only 'New data for the Last 15 16 364 Glacial Maximum in Great Britain and Ireland', Quaternary Science Reviews 21 , 89-101. 17 18 365 BRADWELL, T., STOKER, M. & KRABBENDAM, M. (2008b), 'Megagrooves and streamlined bedrock 19 20 366 in NW Scotland: The role of ice streams in landscape evolution', Geomorphology 97 , 135-156. 21 367 BRADWELL, T., STOKER, M., GOLLEDGE, N., WILSON, C., MERRITT, J., LONG, D., EVEREST, J., 22 23 368 HESTVIK, O., STEVENSON, A., HUBBARD, A., FINLAYSON, A. & MATHERS, H. (2008a), 24 25 369 'The northern sector of the last British Ice Sheet: maximum extent and demise', Earth Science 26 27 370 Reviews 88 , 207-226. 28 29 371 BRITISH GEOLOGICAL SURVEY (1995), Glen Roy, Scotland Sheet 63W, British Geological Survey, 30 31 372 Keyworth, Nottingham. 32 373 BRITISH GEOLOGICAL SURVEY (1997), Fortrose, Scotland Sheet 84W, British Geological Survey, 33 34 374 Keyworth, Nottingham. 35 36 375 BRITISH GEOLOGICAL SURVEY (2000), Dalwhinnie, Scotland Sheet 63E, British Geological 37 38 376 Survey, Keyworth, Nottingham. 39 40 377 BURKE, M., WOODWARD, J., RUSSELL, A., FLEISHER, P. & BAILEY, P. (2010), 'The sedimentary 41 42 378 architecture of outburst flood eskers: A comparison of ground-penetrating radar data from 43 44 379 Bering Glacier, Alaska and Skeiðarárjökull, Iceland', Geological Society of America Bulletin 45 380 122 , 1637-1645. 46 47 381 BURKE, M., WOODWARD, J., RUSSELL, A., FLEISHER, P. & BAILEY, P. (2008), 'Controls on the 48 49 382 sedimentary architecture of a single event englacial esker: Skeiðarárjökull, Iceland', Quaternary 50 51 383 Science Reviews 27 , 1829-1847. 52 53 384 CHEN, C.-Y. & ROSE, J. (2008), Assessment of remote sensed imagery on the analysis of landforms 54 55 385 in Glen Roy, In: PALMER, A., LOWE, J. & ROSE, J., ed., The Quaternary of Glen Roy and 56 57 386 Vicinity, Field Guide , Quaternary Research Association, London, pp. 36-45. 58 59 60 13 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 14 of 26

1 2 3 387 CHIVERRELL, R. & THOMAS, G. (2010), 'Extent and timing of the Last Glacial Maximum (LGM) in 4 5 388 Britain and Ireland: a review', Journal of Quaternary Science 25 , 535-549. 6 7 389 CLARK, C., EVANS, D., KHATWA, A., BRADWELL, T., JORDAN, C., MARSH, S., MITCHELL, W. & 8 390 BATEMAN, M. (2004), 'Map and GIS database of landforms and features related to the last 9 10 391 British Ice Sheet', Boreas 33 , 359-375. 11 12 392 CLARK, C., HUGHES, A., GREENWOOD, S., JORDAN, C. & SEJRUP, H. (2012), 'Pattern and timing 13 14 393 of retreatFor of the last Peer British-Irish Ice Sheet',Review Quaternary Science Only Reviews 44 , 112-146. 15 16 394 DARWIN, C. (1839), 'Observations on the parallel roads of Glen Roy, and of other parts of 17 18 395 in Scotland, with an attempt to prove that they are of marine origin', Philosophical Transactions 19 20 396 of the Royal Society 129 , 39-81. 21 397 DUNLOP, P. & CLARK, C. (2006a), 'Morphological characteristics of ribbed moraine', Quaternary 22 23 398 Science Reviews 25 , 1668-1691. 24 25 399 DUNLOP, P. & CLARK, C. (2006b), 'Distribution of ribbed moraine in Lac Naococane region, central 26 27 400 Quebec, Canada', Journal of Maps v2006 , 59-70. 28 29 401 DYKE, A. (1993), 'Landscapes of cold-centred Late Wisconsinan ice caps, Arctic Canada', Progress 30 31 402 in Physical Geography 17 , 223-247. 32 403 DYKE, A., MORRIS, T., GREEN, D. & ENGLAND, J. (1992), Quaternary geology of Prince of Wales 33 34 404 Island, Arctic Canada, Geological Survey of Canada Memoir 433 , Geological Survey of 35 36 405 Canada. 37 38 406 EVANS, D., (2005), Ice-marginal Terrestrial Landsystems: Active Temperate Glacier Margins, In: 39 40 407 EVANS, D., ed., Glacial Landsystems , Hodder, London, pp. 12-43. 41 42 408 EVANS, I. & COX, N. (1974), 'Geomorphometry and the operational definition of cirques', Area 6, 150- 43 44 409 153. 45 410 EVANS, I. (2006), 'Allometric development of glacial cirque form: geological, relief and regional effects 46 47 411 on the cirques of Wales', Geomorphology 80 , 245-266. 48 49 412 EYLES, N., BOYCE, J. & BARENDREGT, R. (1999), 'Hummocky moraine: sedimentary record of 50 51 413 stagnant Laurentide Ice Sheet lobe resting on soft sediment', Sedimentary Geology 123 , 163- 52 53 414 174. 54 55 415 FARR, T., ROSEN, P., CARO, E., CRIPPEN, R., DUREN, R., HENSLEY, S., KOBRICK, M., PALLER, 56 57 416 M., RODRIGUEZ, E., ROTH, L., SEAL, D., SHAFFER, S., SHIMADA, J., UMLAND, J., 58 59 60 14 URL: http://mc.manuscriptcentral.com/tjom Page 15 of 26 Journal of Maps

1 2 3 417 WERNER, M., OSKIN, M., BURBANK, D. & ALSDORF, D. (2007), 'The Shuttle Radar 4 5 418 Topography Mission', Reviews of Geophysics 45 , RG2004. 6 7 419 FAY, H. (2002), Formation of kettle holes following a glacial-outburst flood (jökulhlaup), 8 420 Skeiðarársandur, southern Iceland, In: SNORRASSON, A., FINNSDOTTIR, H. & MOSS, M., 9 10 421 ed., The Extremes of the Extremes: Extraordinary Floods, IAHS Publication, 271 , IAHS Press, 11 12 422 Oxford, pp. 205-210. 13 14 423 FINLAYSON,For A. (2006), 'GlacialPeer geomorphology Review of the Creag Maegaidh Only Massif, western Grampian 15 16 424 Highlands: implications for local glaciation and palaeoclimate during the Loch Lomond Stadial', 17 18 425 Scottish Geographical Journal 122 , 239-307. 19 20 426 FINLAYSON, A., MERRITT, J., BROWNE, M., MERRITT, J., MCMILLAN, A. & WHITBREAD, K. 21 427 (2010), 'Ice sheet advance, dynamics, and decay configurations: evidence from west central 22 23 428 Scotland', Quaternary Science Reviews 29 , 969-998. 24 25 429 FIRTH, C. (1989a), 'Late Devensian raised shorelines and ice limits in the inner Moray Firth area, 26 27 430 northern Scotland', Boreas 18 , 5-21. 28 29 431 FIRTH, C. (1989b), 'A reappraisal of the supposed Ardersier Readvance, inner Moray Firth', Scottish 30 31 432 Journal of Geology 25 , 249-261. 32 433 FLETCHER, T., AUTON, C., HIGHTON, A., MERRITT, J., ROBERTSON, S. & ROLLIN, K. (1996), 33 34 434 Geology of Fortrose and eastern District : Memoir for 1:50 000 Geological Sheet 84W 35 36 435 (Scotland) , British Geological Survey, Keyworth, Nottingham, pp. 64-100. 37 38 436 GLASSER, N. & JANSSON, K. (2008), 'The Glacial Map of southern South America', Journal of Maps 39 40 437 v2008 , 175-196. 41 42 438 GOLLEDGE, N. (2006), 'The Loch Lomond Stadial glaciation south of Rannoch Moor: New evidence 43 44 439 and palaeoglaciological insights, Scottish', Geographical Journal 122 , 326-343. 45 440 GORDON, J. & MCEWEN, L. (1993), North Esk and West Water glaciofluvial landforms, In: 46 47 441 GORDON, J. & SUTHERLAND, D., ed., Quaternary of Scotland , Joint Nature Conservation 48 49 442 Committee, Chapman and Hall, London, pp. 499-501. 50 51 443 GORDON, J. (1993), Carstairs kames, In: GORDON, J. & SUTHERLAND, D., ed., Quaternary of 52 53 444 Scotland , Chapman and Hall, London, pp. 544-549. 54 55 445 GORDON, J. (2001), 'The corries of the Cairngorm Mountains', Scottish Geographical Journal 117 , 56 57 446 49-62. 58 59 60 15 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 16 of 26

1 2 3 447 GREENWOOD, S. & CLARK, C. (2008), 'Subglacial bedforms of the Irish Ice Sheet', Journal of Maps 4 5 448 v2008 , 332-357. 6 7 449 GREENWOOD, S., CLARK, C. & HUGHES, A. (2007), 'Formalising an inversion methodology for 8 450 reconstructing ice-sheet retreat patterns from meltwater channels: application to the British Ice 9 10 451 Sheet', Journal of Quaternary Science 22 , 637-645. 11 12 452 HÄTTESTRAND, C. & KLEMAN, J. (1999), 'Ribbed moraine formation', Quaternary Science Reviews 13 14 453 18 , 43-61.For Peer Review Only 15 16 454 HÄTTESTRAND, C. & STROEVEN, A. (2002), 'A relict landscape in the centre of Fennoscandian 17 18 455 glaciation: Geomorphological evidence of minimal Quaternary glacial erosion', Geomorphology 19 20 456 44 , 127-143. 21 457 HÄTTESTRAND, C. (1998), 'The glacial geomorphology of central and northern Sweden', Sveriges 22 23 458 Geologiska Undersökning Ca 85 , 1-47. 24 25 459 HUGHES, A., CLARK, C. & JORDAN, C. (2010), 'Subglacial bedforms of the last British Ice Sheet', 26 27 460 Journal of Maps v2010 , 543-563. 28 29 461 JANSSON, K., STOEVEN, A. & KLEMAN, J. (2003), 'Configuration and timing of Ungava Bay ice 30 31 462 streams, Labrador-Ungava, Canada', Boreas 32 , 256-263. 32 463 KEY, R. (1997), Geology of the Glen Roy district : Memoir for 1:50 000 geological sheet 63W 33 34 464 (Scotland) , British Geological Survey, Keyworth, Nottingham, pp. 96-104. 35 36 465 KLEMAN, J. & BORGSTRÖM, I. (1996), 'Reconstruction of Palaeo-ice sheets: The use of 37 38 466 geomorphological data', Earth Surface Processes and Landforms 21 , 893-909. 39 40 467 KLEMAN, J., BORGSTRÖM, I., ROBERTSSON, A.-M. & LILLIESKÖLD, M. (1992), 'Morphology and 41 42 468 stratigraphy from several deglaciations in the Transtrand Mountains, western Sweden', Journal 43 44 469 of Quaternary Science 7, 1-17. 45 470 KLEMAN, J., HÄTTESTRAND, C., BORGSTRÖM, I. & STROEVEN, A. (1997), 'Fennoscandian 46 47 471 palaeoglaciology reconstructed using a glacial geological inversion model', Journal of 48 49 472 Glaciology 43 , 283–299. 50 51 473 KNIGHT, J. & MCCABE, M. (1997), 'Identification and significance of ice-flow-transverse subglacial 52 53 474 ridges (Rogen moraines) in northern central Ireland', Journal of Quaternary Science 12 , 519- 54 55 475 524. 56 57 476 LIVINGSTONE, S., Ó COFAIGH, C. & EVANS, D. (2008), 'Glacial geomorphology of the central 58 59 60 16 URL: http://mc.manuscriptcentral.com/tjom Page 17 of 26 Journal of Maps

1 2 3 477 sector of the last British-Irish Ice Sheet', Journal of Maps v2008 , 358-377. 4 5 478 LUNDQVIST, J. (1989), 'Rogen (ribbed) moraine: identification and possible origin', Sedimentary 6 7 479 Geology 62 , 281-292. 8 480 MARGOLD, M. & JANSSON, K. (2012), 'Evaluation of data sources for mapping glacial meltwater 9 10 481 features', International Journal of Remote Sensing 33 , 2355-2377. 11 12 482 MARGOLD, M., JANSSON, K., KLEMAN, J. & STROEVEN, A. (2011), 'Glacial meltwater landforms of 13 14 483 centralFor British Colombia', Peer Journal of MapsReview v2011 , 486-506. Only 15 16 484 MAY, R. & HIGHTON, A. (1998), Memoir for 1:50 000 geological sheet 73W (Scotland), British 17 18 485 Geological Survey, Keyworth, Nottingham, chapter Geology of the district, pp. 19 20 486 59-62. 21 487 MCCANN, S. (1966), 'The limits of the Late-glacial Highland, or Loch Lomond, Readvance along the 22 23 488 West Highland seaboard from Oban to Mallaig', Scottish Journal of Geology 2, 84-95. 24 25 489 MERRITT, J., AUTON, C. & CALLUM, R. (1995), 'Ice-proximal glaciomarine sedimentation and sea- 26 27 490 level change in the Inverness area, Scotland: a review of the deglaciation of a major ice stream 28 29 491 of the British Late Devensian ice sheet', Quaternary Science Reviews 14 , 289-329. 30 31 492 MITCHELL, W. & RILEY, J. (2006), 'Drumlin map of the Western Pennines and southern Vale of 32 493 Eden, Northern England, UK', Journal of Maps v2006 , 10-16. 33 34 494 NYE, J. (1973), 'Water at the bed of a glacier', IASH Publication (Symposium at Cambridge 1969 – 35 36 495 Hydrology of Glaciers) 95 , 189-194. 37 38 496 PALMER, A., ROSE, J., LOWE, J. & MACLEOD, A. (2010), 'Annually resolved events of the Younger 39 40 497 Dryas glaciation in Lochaber (Glen Roy and Glen Spean), Western Scottish Highlands', Journal 41 42 498 of Quaternary Science 25 , 581-596. 43 44 499 PEACOCK, J. (1971), 'Terminal features of the Creran Glacier of Loch Lomond Readvance age in 45 500 western Benderloch, , and their significance in the late-glacial history of the 46 47 501 area', Scottish Journal of Geology 7, 349-356. 48 49 502 PEACOCK, J., MENDUM, J. & FETTES, D. (1992), Geology of the Glen Affric district : Memoir for 50 51 503 1:50,000 geological sheet 72E (Scotland) , British Geological Survey, Keyworth, Nottingham, 52 53 504 pp. 69-77. 54 55 505 RODRIGUEZ, E., MORRIS, C., BELZ, J., CHAPIN, E., MARTIN, J., DAFFER, W. & HENSLEY, S. 56 57 506 (2005), 'An assessment of the SRTM topographic products, Technical Report JPL D-31639', 58 59 60 17 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 18 of 26

1 2 3 507 Technical report, Jet Propulsion Laboratory, Pasedina, California. 4 5 508 RUSSELL, A. & MARREN, P. (1998), 'A Younger Dryas (Loch Lomond Stadial) jökulhlaup deposit, 6 7 509 Fort Augustus, Scotland', Boreas 27 , 231-242. 8 510 SEJRUP, H., HJELSTUEN, B., DAHGREN, K., HAFLIDASON, H., KUIJPERS, A., NYGÅRD, A., 9 10 511 PRAEG, D., STOKER, M. & VORREN, T. (2005), 'Pleistocene glacial history of the NW 11 12 512 European continental margin', Marine and Petroleum Geology 22 , 1111-1129. 13 14 513 SEJRUP, H.,For NYGÅRD, A.,Peer HALL, A. & HAFLIDASON, Review H. (2009), 'Middle Only and Late Weichselian 15 16 514 (Devensian) glaciation history of south-western Norway, North Sea and eastern UK', 17 18 515 Quaternary Science Reviews 28 , 370-380. 19 20 516 SHARPE, D. & SHAW, J. (1989), 'Erosion of bedrock by subglacial meltwater, Cantley, Quebec', 21 517 Geological Society of America Bulletin 101 , 1011-1020. 22 23 518 SISSONS, J. & Cornish, R. (1982), 'Differential glacio-isostatic uplift of crustal blocks at Glen Roy, 24 25 519 Scotland', Quaternary Research 18 , 268-288. 26 27 520 SISSONS, J. (1967), The Evolution of Scotland’s Scenery , Oliver and Boyd, Edinburgh. 28 29 521 SISSONS, J. (1976), The Geomorphology of the British Isles: Scotland , Methuen and Co. Ltd., 30 31 522 London. 32 523 SISSONS, J. (1977a), 'Former ice-dammed lakes in Glen Moriston, Inverness-shire, and their 33 34 524 significance in upland Britain', Transactions of the Institute of British Geographers New Series 35 36 525 2, 224-242. 37 38 526 SISSONS, J. (1977b), The parallel roads of Glen Roy , Nature Conservancy Council, London. 39 40 527 SISSONS, J. (1978), 'The parallel roads of Glen Roy and adjacent glens, Scotland', Boreas 7, 229- 41 42 528 244. 43 44 529 SISSONS, J. (1979a), 'The Loch Lomond Stadial in the British Isles', Nature 280 , 199-203. 45 530 SISSONS, J. (1979b), 'Catastrophic lake drainage in Glen Spean and the Great Glen, Scotland', 46 47 531 Journal of the Geological Society of London 139 , 215-224. 48 49 532 SISSONS, J. (1979c), 'The limit of the Loch Lomond Advance in Glen Roy and vicinity', Scottish 50 51 533 Journal of Geology 15 , 31-42. 52 53 534 SMITH, M. & CLARK, C. (2005), 'Methods for the visualization of digital elevation models for landform 54 55 535 mapping', Earth Surface Processes and Landforms 30 , 885-900. 56 57 536 SMITH, M., ROSE, J. & BOOTH, S. (2006), 'Geomorphological mapping of glacial landforms from 58 59 60 18 URL: http://mc.manuscriptcentral.com/tjom Page 19 of 26 Journal of Maps

1 2 3 537 remotely sensed data: An evaluation of the principal data sources and an assessment of their 4 5 538 quality', Geomorphology 76 , 148-165. 6 7 539 SOLLID, J. & SØRBEL, L. (1994), 'Distribution of glacial landforms in Southern Norway in relation to 8 540 the thermal regime of the last continental ice sheet', Geografiska Annaler 76 A , 25-35. 9 10 541 SPAGNOLO, M. & CLARK, C. (2009), 'A geomorphological overview of glacial landforms on the 11 12 542 Icelandic continental shelf', Journal of Maps v2009 , 37-52. 13 14 543 SUGDEN, D.,For DENTON, PeerG. & MARCHANT, Review D. (1991), 'Subglacial Meltwater Only Channel Systems and 15 16 544 Ice Sheet Overriding, Asgard Range, Antarctica', Geografiska Annaler 73 A , 109-121. 17 18 545 THORP, P. (1986), 'A mountain ice field of Loch Lomond Stadial age, western Grampians, Scotland', 19 20 546 Boreas 15 , 83-97. 21 547 TURNER, A., WOODWARD, J., DUNNING, S., SHINE, A., STOKES, C. & Ó COFAIGH, C. (2012), 22 23 548 'Geophysical surveys of the sediments of Loch Ness, Scotland: implications for the deglaciation 24 25 549 of the Moray Firth Ice Stream, British–Irish Ice Sheet', Journal of Quaternary Science 27 , 221- 26 27 550 232. 28 29 551 TURNER, A., WOODWARD, J., DUNNING, S., SHINE, A., STOKES, C. & Ó COFAIGH, C. (2013a). 30 31 552 ‘The deglaciation of the Great Glen based on the results of geophysical surveys within Loch 32 553 Ness’. In: Boston, C.M., Lukas, S. and Merritt, J.W. (eds.). The Quaternary of the Monadhliath 33 34 554 Mountains and Great Glen, Field Guide . Quaternary Research Association, London, pp. 83-88. 35 36 555 TURNER, A., WOODWARD, J., DUNNING, S., SHINE, A., STOKES, C. & Ó COFAIGH, C. (2013b). 37 38 556 ‘Evidence from geophysical surveys for Younger Dryas (jökulhlaup) sedimentation within Loch 39 40 557 Ness’. In: Boston, C.M., Lukas, S. and Merritt, J.W. (eds.). The Quaternary of the Monadhliath 41 42 558 Mountains and Great Glen, Field Guide . Quaternary Research Association, London, pp. 89-92. 43 44 559 YOUNG, J. (1978), 'The landforms of the upper Strathspey, Scottish Geographical Magazine', 45 560 Scottish Geographical Magazine 94 , 76-94. 46 47 561 48 562 49 50 51 52 53 54 55 56 57 58 59 60 19 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 20 of 26

1 2 3 563 9. Tables 4 1 5 564 Table 1 – Statistical properties calculated for glacial landforms. 6 565 Mean Mean L/W Mean Mean Glacial Landform N 7 Length (m) Width (m) Ratio Orientation (°) Area (km²) 8 Cirques 277 1155 ± 811 1038 ± 553 1.4:1 89.2 ± 50.98 1.42 ± 1.78 9 Arêtes 77 1804 ± 1462 - - - - 10 Eskers 553 222 ± 202 - - 65.2 ± 45.0 - 11 12 Glacial Lineations 1977 290 ± 377 158 ± 132 4.2:1 47.9 ± 23.9 0.13 ± 0.26 13 Crag & Tail 314 482 ± 400 111 ± 82 4.4:1 49.1 ± 37.5 0.5 ± 0.09 14 Drumlins For Peer 181 778 ± 750Review 189 ± 154 3.9:1 Only 46.4 ± 22.2 0.18 ± 0.33 15 Streamlined Bedrock 1482 268 ± 260 55 ± 35 5.0:1 47.4 ± 18.2 0.01 ± 0.07 16 17 Kames 387 - - - - - 18 Kame & Kettle 337 - - - - - Kame Terraces 50 355 ± 252 - - 76.6 ± 34.5 - 19 20 Meltwater Channels 4117 413 ± 347 - - 74. 7 ± 46. 2 - 21 Lateral 2468 310 ± 293 - - 76.8 ± 46.3 - 22 Sublateral 221 377 ± 323 - - 94.2 ± 49.4 - 23 Subglacial 1418 560 ± 413 - - 68.0 ± 44.3 - 24 Proglacial 3 229 ± 68 - - 112.9 ± 7.8 - 25 Over-col 7 858 ± 449 - - 58.6 ± 50.1 - 26 27 Moraines 10227 116 ± 114 - - 90.0 ± 52.3 - 28 Transverse 3397 128 ± 107 - - 98.8 ± 55.6 - Longitudinal 3478 149 ± 143 - - 77.8 ± 46.5 - 29 Hummocky 3077 62 ± 45 - - - - 30 Ribbed 275 243 ± 180 - - 105.9 ± 64.3 - 31 32 1 Standard deviations (±) are derived from the square root of the variance within each landform population. 33 566 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 20 URL: http://mc.manuscriptcentral.com/tjom Page 21 of 26 Journal of Maps

1 2 3 4 5 6 7 8 9 10 11 12 13 14 For Peer Review Only 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 Figure 1 – Map to show locations described in the text with figure extents. CF = Cromarty Firth; MF = Moray 44 Firth; LU = Loch Ussie; SP = Strathpeffer; IF = Inverness Firth; SC = Strathconnon; BF = Beauly Firth; I = 45 Inverness; L = Lochend; D = Dores; LD = Loch Duntelchaig; RC = River Clava; UB = Urquhart Bay; SF = 46 Strathfarrar; LM = Loch Mullardoch; GA = Glen Affric; GU = ; LN = Loch Ness; SE = 47 Stratherrick; RF = River Findhorn; Laf = Loch Affric; GD = Glen Doe; GM = Glen Moriston; FA = Fort Augustus; AT = Auchteraw Terrace; LC = Loch Cluanie; LQ = Loch Quioch; Lloy = Loch Loyne; Gar = Glen 48 Garry; LG = ; LO = ; GT = Glen Turret; GR = Glen Roy; Ggl = Glen Gloy; LA = Loch 49 Arkaig; LL = ; La = Loch Laggan; SS = Strathspey; LS = ; LE = Loch Eil; Lab = Loch 50 Aber; FW = Fort William; BN = Ben Nevis; BNM = Ben Nevis Mountain Range; LT = Loch Treig; SO = 51 Strathossian; Los = Loch Ossian; Ler = Loch Ericht; BW = Blackwater Reservoir; RM = Rannoch Moor; La i = 52 Loch Laidon; LB = Loch Ba. 53 54 55 56 57 58 59 60 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 22 of 26

1 2 3 4 5 6 7 8 9 10 11 12 13 14 For Peer Review Only 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 Figure 2 – a) Map data showing glacial valleys surrounding the peak of Mullach nan Coirean, Ben Nevis Mountains. b) Interpreted image with cirque and arête features identified in green. c) Streamlined landforms 48 found on the high ground to the west of Loch Ness. d) Interpreted image with crag and tails (yellow) and 49 streamlined bedrock (red) identified. e) Extract from south of the Beauly Firth (BF). f) Interpreted image 50 with drumlins identified in purple. LB = Loch Bruicheach. 51 52 53 54 55 56 57 58 59 60 URL: http://mc.manuscriptcentral.com/tjom Page 23 of 26 Journal of Maps

1 2 3 4 5 6 7 8 9 10 11 12 13 14 For Peer Review Only 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 Figure 3 – a) NextMap data showing a field of ridges perpendicular to the long axis of Blackwater Reservoir. b) Interpreted image with transverse moraines identified. c) NextMap data showing ridges aligned parallel to 48 the valley long axis in proximity to Loch Ossian, cross-cut by a modern railway line and coming into contact 49 with valley slopes. d) Interpreted image with longitudinal moraines identified. e) NextMap image showing 50 ridges with an anastomosing pattern from Cromarty Firth. f) Interpreted image with ribbed moraine 51 identified and associated with a palaeo-shoreline mapped by Firth (1989a). g) NextMap data from Rannoch 52 Moor showing a field of chaotically distributed mounds. h) Interpreted image with hummocky moraine 53 identified; no clear linear trends exist. Ice flow directions are indicated. See figure 1 for locations. 54 55 56 57 58 59 60 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 24 of 26

1 2 3 4 5 6 7 8 9 10 11 12 13 14 For Peer Review Only 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 Figure 4 – a) NextMap data showing chaotic surface morphology north of Newtonmore. b) Interpreted image with kame and kettle topography identified. c) NextMap data showing linear terraces aligned parallel to the 48 valley axis in Glen Moriston . d) Interpreted image with kame terraces identified. e) NextMap image showing 49 numerous channelised features around Leum Uilleim, Rannoch Moor. f) Interpreted image with lateral, 50 sublateral, subglacial and over-col spillways identified. g) NextMap data fro m western Strathspey showing a 51 field of sinuous, sharp crested ridges. h) Interpreted image with eskers identified. See figure 1 for locations. 52 53 54 55 56 57 58 59 60 URL: http://mc.manuscriptcentral.com/tjom Page 25 of 26 Journal of Maps

1 2 3 4 5 6 7 8 9 10 11 12 13 14 For Peer Review Only 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 Figure 5 – Reconstruction of the waning stages of ice dammed lake development based on shorelines mapped in this study and before complete drainage. a) Glen Doe 510 m; b) Glen Doe 406 m; c) Glen Doe 48 359 m; d) Glen Doe 334 m; e) Glen Doe 324 m; f) Glen Doe 305 m; g) Glen Gloy 355 m maximum extent; 49 h) Glen Gloy 355 m minimum extent; i) Glen Roy 350 m and Glen Spean 260 m; j) Glen Roy 325 m and 50 Glen Spean 260 m; k) Spean/Roy 260 m. Drainage has been interpreted to be via a series of outburst fl oods 51 (jökulhlaups) (Sissons, 1977a; 1979b). Dashed lines indicate ice margins. 52 53 54 55 56 57 58 59 60 URL: http://mc.manuscriptcentral.com/tjom Journal of Maps Page 26 of 26

1 2 3 N 5°40'0"W 5°20'0"W 5°0'0"W 4°40'0"W 4°20'0"W 4°0'0"W

4 " 0

5 ' 6 0 4

7 ° 7 12°0'0"W 10°0'0"W 8°0'0"W 6°0'0"W 4°0'0"W 2°0'0"W 0°0'0" 2°0'0"E

8 5 N

9 " 0 10 ' N 0 5 N ° 0 11 " 0 " 9 2 0 , 0 ' 5 .

12 ' h al nt 0 t t e >18 ka ? 0 13 e t ° r 4 x p 9

A Glacial Geomorphological Map of ° 14 i u E h r 5 7 j M F t e G

15 5 ir S L ~18 ka 16 y N t F "

17 0

r '

18 y 0 N a ° 14 ka 15 ka the Great Glen Region, Scotland, UK " 19 a 8 0 5 m r '

20 13.5 ka 0

o o °

21 r 8

M 5 22 C 13 ka 23 N

24 "

1 2 0 25 1 ' 0 N Andrew J. Turner , John Woodward , Chris R. Stokes , ° 26 " 7

2 0 ' 27 1 5 0

28 Colm Ó Cofaigh , Stuart Dunning ° 7 29 th 5 30 r i B N 31 N 1 o "

" F w 32 0 ' 0 e

' Faculty of Engineering and Environment, Northumbria L

0 n 33 s G N ° 0 e "

s 6 M 3 34 t 0 '

5 ° e E a University, Ellison Place, Newcastle Upon Tyne, NE1 0

35 7 l n x ., °

5 t 36 r e 2 6 n 0 5 37 8ST; [email protected] e t 0 v 2

38 N N " 39 In " 0 0 ' 40 ' 0 N 2 Beauly Firth 0 ° " 3

41 5 0 °

Department of Geography, Durham University, South ' 5 7

42 0 ° 5

43 5

44 Road, Durham, DH1 3LE, UK 5 45

46 N " 0

47 ' 0 N

Mapped from Intermap Technologies NEXTMap ° 48 " 4 0 '

49 5 0

50 Data (NERC Earth Observation Data Centre) ° 4

51 5 52

53 N 54 " 0 Projection: Transverse Mercator, ' N 55 0 ° " 3 56 0 ' 5 57 airy spheriod, OSGB1936 0 °

58 3 5 59 N "

60 0 ' N 0 " 2 0 ' ° N 0 7 " ° 0 5 2 ' 5 s 0 °

s 2 N e 5 " 0 N ' 0 N "

h 2 0 ° c ' N 7 0 " °

o 5 0 1 L ' 5 0 ° 1 5 N " 0 ' 0 ° 0 5

10°0'0"W 8°0'0"W 6°0'0"W 4°0'0"W 2°0'0"W 0°0'0" 2°0'0"E N

" For Peer Review Only 0 ' 0 1 °

7 NW Highlands 5 Above: Inset showing major retreat N

" configurations of the former British- 0 ' 0

Strathspey 1 Irish Ice Sheet with the current study ° 7 5 area in context. Numbered retreats are interpreted from Merritt et al. (1995).

h Below: Inset showing Shuttle Radar ic O Topography Mission (SRTM) 90 m h c resolution DEM of the Great Glen and o L surrounding regions. N

" µ 0 ' 0

° Grampian Mountains 7 5

5°30'0"W 5°0'0"W 4°30'0"W 4°0'0"W N

y " 0

h ' c 0 °

o 7 L 5 h c N

o " 0 L ' 0 N 3 " Legend ° 0 7 ' 5 0 3 ° 7

Cirques / Arêtes Streamlined Bedrock 5 Crag & Tails Study Area Drumlins YD Limit N " N 0 ' " 5 0 N ' Eskers Ice Dammed Lakes 1 " ° 0 0 7 ' 5 5 5 ° 1 6 Glen Doe (305m) ° 5 Kame & Kettle 7 5 N

Kame Terrace Glen Doe (324m) " 0 ' 0 5

Meltwater Channels Glen Doe (334m) ° 6 5 N Lateral " 0

Glen Doe (359m) ' 0 N ° " 7 0 5 Over-col Spillway '

Glen Doe (406m) 0 ° 7 Proglacial Glen Doe (510m) 5 Legend Sublateral Glen Gloy (355m Min.) SRTM (90m) Subglacial N Glen Gloy (355m Max.) " 0 ' 5

Altitude (m) N 4 " ° N Moraines 0 6 ' " Spean/Roy (260m) 5 5 0 ' 1345 4 ° 0 6

4 Hummocky 5 ° Glen Roy (325m) 6 5 Longitudinal Glen Roy (350m) N

" 0 0 e Rogen ' h Altitude 0 4

n ° 6

in Transverse Above 630 m 5 5°30'0"W 5°0'0"W 4°30'0"W 4°0'0"W L h c o L Kilometers

0 3.5 7 14 21 28 © Journal of Maps, 2013 5°20'0"W 5°0'0"W 4°40'0"W 4°20'0"W 4°0'0"W 3°40'0"W

URL: http://mc.manuscriptcentral.com/tjom