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Figure 4. stratigraphical sections in the south face of Brannam’s Claypit, Fremington (after Wood, in Straw, 1974

Figure 4 stratigraphical sections in the south face of Brannam’s Claypit, Fremington (after Wood, in Straw, 1974

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Figure 1. Pleistocene glacial limits in SW England (from Gibbard et al., 2017).
Figure 1. Pleistocene glacial limits in SW England (from Gibbard et al., 2017).
Figure 2. Location of main places mentioned in the text, and of sites of mammalian remains.
Figure 2. Location of main places mentioned in the text, and of sites of mammalian remains.
Figure 3. Quaternary deposits in the Fremington—Hele area (after Stephens, 1970
Figure 3. Quaternary deposits in the Fremington—Hele area (after Stephens, 1970
Figure 5. Brannams Claypit as it appeared in 1903. Brian John (https,/brian-mountainman. blogspot.com/2020/04/the- fremington-enigma.himl) consulted 1/9/23.
Figure 5. Brannams Claypit as it appeared in 1903. Brian John (https,/brian-mountainman. blogspot.com/2020/04/the- fremington-enigma.himl) consulted 1/9/23.
they described as ‘a typical flat-iron subglacial cobble, with exceptionally well-striated faces’ and ‘unequivocally glacially transported’. They favoured deposition during MIS 12 (.e., during the Anglian glacial Stage) on the basis of preliminary optically stimulated luminescence (OSL) dating of Unit C of the series, though the authors comment that the dates obtained have large uncertainties. Preliminary amino- Poo lad ELI ALLIIULTIL ALINE LIALUIL VWI LLIN AVALIAIJILN CVINILTILG, An alternative interpretation of the glacial deposits is that the different strata merely reflect sequential changes ir the conditions of glacial sedimentation, involving englacia' and/or subglacial lake(s), without necessarily involving ice- marginal oscillations. Another suggestion, by Eyles anc McCabe (1989), was that the supposed glacial deposits a Fremington, together with those at Trebetherick in Cornwal| (Cullingford, 1998), may be glaciomarine mud drapes. laic down beyond the Late Devensian ice sheet. A detailed re- examination at Brannam’s Claypit by Croot et al. (1996), using stratigraphical, sedimentological, petrological, geotechnical anc micropalaeontological techniques, confirmed the glaciofluvia or fluvial origin of the basal gravel, and concluded that the bulk of the Fremington Clay Series is probably glaciolacustrine in origin (although a glaciomarine origin cannot be completely ruled out), and has been overridden by glacier ice (see review in Scourse and Furze, 2001, p. 428). They found only one errati« amongst the dropstones scattered through the clay, which
they described as ‘a typical flat-iron subglacial cobble, with exceptionally well-striated faces’ and ‘unequivocally glacially transported’. They favoured deposition during MIS 12 (.e., during the Anglian glacial Stage) on the basis of preliminary optically stimulated luminescence (OSL) dating of Unit C of the series, though the authors comment that the dates obtained have large uncertainties. Preliminary amino- Poo lad ELI ALLIIULTIL ALINE LIALUIL VWI LLIN AVALIAIJILN CVINILTILG, An alternative interpretation of the glacial deposits is that the different strata merely reflect sequential changes ir the conditions of glacial sedimentation, involving englacia' and/or subglacial lake(s), without necessarily involving ice- marginal oscillations. Another suggestion, by Eyles anc McCabe (1989), was that the supposed glacial deposits a Fremington, together with those at Trebetherick in Cornwal| (Cullingford, 1998), may be glaciomarine mud drapes. laic down beyond the Late Devensian ice sheet. A detailed re- examination at Brannam’s Claypit by Croot et al. (1996), using stratigraphical, sedimentological, petrological, geotechnical anc micropalaeontological techniques, confirmed the glaciofluvia or fluvial origin of the basal gravel, and concluded that the bulk of the Fremington Clay Series is probably glaciolacustrine in origin (although a glaciomarine origin cannot be completely ruled out), and has been overridden by glacier ice (see review in Scourse and Furze, 2001, p. 428). They found only one errati« amongst the dropstones scattered through the clay, which
Figure 8. Glaciated ice-moulded bedrock on Lundy. (from Rolfe et al., 2012). Photograph by Philip Hughes. Published with permission from Elsevier (License Number: 5820300258442).
Figure 8. Glaciated ice-moulded bedrock on Lundy. (from Rolfe et al., 2012). Photograph by Philip Hughes. Published with permission from Elsevier (License Number: 5820300258442).
Figure 10. Possible glacial diversion of drainage in the Barnstaple area (after Edmonds, 1972a)
Figure 10. Possible glacial diversion of drainage in the Barnstaple area (after Edmonds, 1972a)
Figure 11. Jor types on Dartmoor. a) Type 2 tor, b) and c) Type 1 tor, d) spatial distribution of the three types on Dartmoor (from Harriot and Evans, 2022).
Figure 11. Jor types on Dartmoor. a) Type 2 tor, b) and c) Type 1 tor, d) spatial distribution of the three types on Dartmoor (from Harriot and Evans, 2022).
Figure 12. Weathering profile of decomposed granite (‘growan’), Two Bridges Quarry, Dartmoor. Note intact granite in lower left and unconsolidated growan several metres thick (photograph by J.B. Murton).
Figure 12. Weathering profile of decomposed granite (‘growan’), Two Bridges Quarry, Dartmoor. Note intact granite in lower left and unconsolidated growan several metres thick (photograph by J.B. Murton).
study of quartz-grain surface textures that the most weathered growan was produced mainly by mechanical disintegration, thus favouring a wholly periglacial origin of the tors. Only samples of growan at the same depth as buried incipient tors at Two Bridges Quarry displayed evidence of chemically decomposed granite consistent with Linton’s (1955) hypothesis. Gerrard (1974, 1978) has confirmed that tors are located where joint spacings have permitted differential weathering and erosion. regouths Gmantles of weathered material) in conjunction with frost-shattering processes in a periglacial environment, and that both exhumation and modification of two-cycle tors and the formation of one-cycle tors could have occurred at the same time in different parts of Dartmoor (French, 1976). The large summit tors likely record a composite origin from chemical weathering and frost action, whereas many of the valley- side tors result from periglacial processes (Gerrard, 1994). Additionally, there is clear evidence that chemical weathering of granite currently occurs on Dartmoor (Williams ef al., 1986), and it is likely that chemical, physical and perhaps biological weathering currently contribute to micro-erosion of granite tors and boulders. Tors on non-granitic rocks which show no evidence of deep weathering, as in the Dartmoor aureole (for example at Cox Tor, near Merrivale), in north Devon (such as the Valley of Rocks) and in south Devon (such as between Signalhouse Point [SX 771 355] and Start Point [SX 830 371; Fig. 13] are less ambiguously the products of gelifraction and gelifluction, and in some cases are associated with cryoplanation features.
study of quartz-grain surface textures that the most weathered growan was produced mainly by mechanical disintegration, thus favouring a wholly periglacial origin of the tors. Only samples of growan at the same depth as buried incipient tors at Two Bridges Quarry displayed evidence of chemically decomposed granite consistent with Linton’s (1955) hypothesis. Gerrard (1974, 1978) has confirmed that tors are located where joint spacings have permitted differential weathering and erosion. regouths Gmantles of weathered material) in conjunction with frost-shattering processes in a periglacial environment, and that both exhumation and modification of two-cycle tors and the formation of one-cycle tors could have occurred at the same time in different parts of Dartmoor (French, 1976). The large summit tors likely record a composite origin from chemical weathering and frost action, whereas many of the valley- side tors result from periglacial processes (Gerrard, 1994). Additionally, there is clear evidence that chemical weathering of granite currently occurs on Dartmoor (Williams ef al., 1986), and it is likely that chemical, physical and perhaps biological weathering currently contribute to micro-erosion of granite tors and boulders. Tors on non-granitic rocks which show no evidence of deep weathering, as in the Dartmoor aureole (for example at Cox Tor, near Merrivale), in north Devon (such as the Valley of Rocks) and in south Devon (such as between Signalhouse Point [SX 771 355] and Start Point [SX 830 371; Fig. 13] are less ambiguously the products of gelifraction and gelifluction, and in some cases are associated with cryoplanation features.
Figure 14. Cryoplanation terrace and riser developed on metadolerite, Cox Tor, near Merrivale, Dartmoor (photograph by J.B Murton).
Figure 14. Cryoplanation terrace and riser developed on metadolerite, Cox Tor, near Merrivale, Dartmoor (photograph by J.B Murton).
‘igure 15. Dells developed on schist near West Cliff, Bolberry, south Devon. Head deposits (granular) are mapped by the British reological Survey beneath the stream-occupied valley in the centre of the photograph, extending upslope into the lower parts of tk idjacent dells. Hillside tors are visible on the right hillslope that leads down into the main valley (photograph by J.B. Murton).
‘igure 15. Dells developed on schist near West Cliff, Bolberry, south Devon. Head deposits (granular) are mapped by the British reological Survey beneath the stream-occupied valley in the centre of the photograph, extending upslope into the lower parts of tk idjacent dells. Hillside tors are visible on the right hillslope that leads down into the main valley (photograph by J.B. Murton).
Figure 16. a) Tors and hillslopes strewn with large boulders (‘litter’) developed on granite, Staple Tors, near Merrivale, Dartmoor. b) Boulder lobes at Great Mis Tor (photographs by J.B. Murton). c) Boulder stripes radiating out downslope from blockfield surrounding Great Staple Tor. Aerial view from Google Earth.
Figure 16. a) Tors and hillslopes strewn with large boulders (‘litter’) developed on granite, Staple Tors, near Merrivale, Dartmoor. b) Boulder lobes at Great Mis Tor (photographs by J.B. Murton). c) Boulder stripes radiating out downslope from blockfield surrounding Great Staple Tor. Aerial view from Google Earth.
Figure 18. Apron of granular head deposits above rock platform developed on schist between Prawle Point and Langerstone Point, south Devon. Hillside tors in background developed along the old cliff-line and contributed debris to the head deposits (photograph by J.B. Murton).
Figure 18. Apron of granular head deposits above rock platform developed on schist between Prawle Point and Langerstone Point, south Devon. Hillside tors in background developed along the old cliff-line and contributed debris to the head deposits (photograph by J.B. Murton).
Figure 19. Crude stratification in granular head deposits above rock platform developed on schist between Prawle Point and Langerstone Point, south Devon (photograph by J.B. Murton).
Figure 19. Crude stratification in granular head deposits above rock platform developed on schist between Prawle Point and Langerstone Point, south Devon (photograph by J.B. Murton).
thick rest in different places upon one or more of the following: old shore platforms, erratic blocks, raised-beach deposits, or cemented blown sands. The head consists mostly of angular slate fragments, in some places with no finer material (.e., breccia), and in others set in a sandy matrix. As on Dartmoor, there has been debate as to how many solifluction phases are recorded in the colluvial stratigraphy; Stephens (1966, 1970, 1998) claimed that two heads (representing different cold- climate intervals) were present, and Kidson (1971) maintained that there was only one. The nature of the evidence that has evoked such conflicting interpretations is exemplified by an exposure at Middleborough, in Croyde Bay, which shows a layer of coarse, angular slate fragments underlain and overlain by finer material consisting of smaller slate fragments in a sandy matrix (see review by Campbell and Gilbert, 1998). Such variations can readily be explained in terms of a single cold phase, during the onset of which the downslope transfer was mainly of previously weathered material; this was followed by a period when the stripped rock faces, exposed to severe frost action, yielded abundant gelifracts (frost-shattered fragments). After this there was renewed transfer of finer material when the climate had ameliorated sufficiently for frost-shattering of bedrock to give way in importance to chemical weathering and the comminution of existing rock fragments. Although frost cracks and occasional wedge structures interpreted as ice- wedge pseudomorphs in the coarse pebbly stratum may imply renewed severe cold, following the ending of downslope movement, as suggested by Stephens, there is no evidence to support his view that the ice-wedge formation and overlying diamicton were the only elements in the sequence to have formed in the Devensian Stage, which included enough climatic fluctuations to accommodate all elements of the = Coastal diamicton aprons are also prominent in north Devon, producing long, sweeping, concave lower hillslopes that are particularly striking between Barnstaple and Saunton, and around Croyde Bay. Along the northern fringes and valleys of Exmoor, however, many slopes have been stripped almost entirely of regolith. Cliff exposures between Saunton and Baggy Point (Fig. 6) show that the granular head deposits up to 20 m
thick rest in different places upon one or more of the following: old shore platforms, erratic blocks, raised-beach deposits, or cemented blown sands. The head consists mostly of angular slate fragments, in some places with no finer material (.e., breccia), and in others set in a sandy matrix. As on Dartmoor, there has been debate as to how many solifluction phases are recorded in the colluvial stratigraphy; Stephens (1966, 1970, 1998) claimed that two heads (representing different cold- climate intervals) were present, and Kidson (1971) maintained that there was only one. The nature of the evidence that has evoked such conflicting interpretations is exemplified by an exposure at Middleborough, in Croyde Bay, which shows a layer of coarse, angular slate fragments underlain and overlain by finer material consisting of smaller slate fragments in a sandy matrix (see review by Campbell and Gilbert, 1998). Such variations can readily be explained in terms of a single cold phase, during the onset of which the downslope transfer was mainly of previously weathered material; this was followed by a period when the stripped rock faces, exposed to severe frost action, yielded abundant gelifracts (frost-shattered fragments). After this there was renewed transfer of finer material when the climate had ameliorated sufficiently for frost-shattering of bedrock to give way in importance to chemical weathering and the comminution of existing rock fragments. Although frost cracks and occasional wedge structures interpreted as ice- wedge pseudomorphs in the coarse pebbly stratum may imply renewed severe cold, following the ending of downslope movement, as suggested by Stephens, there is no evidence to support his view that the ice-wedge formation and overlying diamicton were the only elements in the sequence to have formed in the Devensian Stage, which included enough climatic fluctuations to accommodate all elements of the = Coastal diamicton aprons are also prominent in north Devon, producing long, sweeping, concave lower hillslopes that are particularly striking between Barnstaple and Saunton, and around Croyde Bay. Along the northern fringes and valleys of Exmoor, however, many slopes have been stripped almost entirely of regolith. Cliff exposures between Saunton and Baggy Point (Fig. 6) show that the granular head deposits up to 20 m
Figure 21. Earth hummocks on hillslope to east of Cox Tor, near Merrivale, Dartmoor (photograph by J.B. Murton).
Figure 21. Earth hummocks on hillslope to east of Cox Tor, near Merrivale, Dartmoor (photograph by J.B. Murton).
Figure 22. Maps showing the extent of past permafrost and seasonally frozen ground in Great Britain (a—g) and (h) Eurasia during: (a) the Late Devensian glacial maximum; (b) 20 ka; (c) 74-59 ka (Early Pleniglacial; MIS 4); (d) 41-38 ka (Middle Pleniglacial cold interval in MIS 3); (e) 27-20 ka (maximum cold of the Late Pleniglacial; approximating the LGM); (f) ~20-15 ka (final phase of the Late Pleniglacial); (g) ~12.9-11.5 ka (Younger Dryas Stadial); and (h) 25-17 ka (Last Permafrost Maximum). Dark blue and light blue lines in (h) indicate southern limits of the continuous and discontinuous permafrost zones, respectively, outside of mountain areas. Adapted from (a) Williams (1969), (b) Van Vliet-Lanoé (2000); (()-(f) Huijzer and Vandenberghe (1998); (g) Isarin (1997) and (bh) Vandenberghe et al. (2014). Ice sheets and glaciers are omitted for clarity. Source: Murton and Ballantyne (2017).
Figure 22. Maps showing the extent of past permafrost and seasonally frozen ground in Great Britain (a—g) and (h) Eurasia during: (a) the Late Devensian glacial maximum; (b) 20 ka; (c) 74-59 ka (Early Pleniglacial; MIS 4); (d) 41-38 ka (Middle Pleniglacial cold interval in MIS 3); (e) 27-20 ka (maximum cold of the Late Pleniglacial; approximating the LGM); (f) ~20-15 ka (final phase of the Late Pleniglacial); (g) ~12.9-11.5 ka (Younger Dryas Stadial); and (h) 25-17 ka (Last Permafrost Maximum). Dark blue and light blue lines in (h) indicate southern limits of the continuous and discontinuous permafrost zones, respectively, outside of mountain areas. Adapted from (a) Williams (1969), (b) Van Vliet-Lanoé (2000); (()-(f) Huijzer and Vandenberghe (1998); (g) Isarin (1997) and (bh) Vandenberghe et al. (2014). Ice sheets and glaciers are omitted for clarity. Source: Murton and Ballantyne (2017).
Figure 24. Relict periglacial landscape of rounded convexo—concave hillslopes developed on the frost-susceptible slate lowland oy the South Hams, south Devon. Valleys were incised by periglacial weathering and erosion during the Pleistocene into a low-relief erosional surface at ~130 m asl (most evident on the skyline) probably inherited from the Neogene. View looking south towards from Wrangaton golf course, on the southern margin of Dartmoor (photograph by J.B. Murton).
Figure 24. Relict periglacial landscape of rounded convexo—concave hillslopes developed on the frost-susceptible slate lowland oy the South Hams, south Devon. Valleys were incised by periglacial weathering and erosion during the Pleistocene into a low-relief erosional surface at ~130 m asl (most evident on the skyline) probably inherited from the Neogene. View looking south towards from Wrangaton golf course, on the southern margin of Dartmoor (photograph by J.B. Murton).
Figure 25. Drainage patterns in Devon showing radial drainage from Dartmoor and short north coast river: reflecting regional dip. Most of the rivers in Devon flow from north to south (Fig. 25), reflecting the overall regional dip. The high ground formed by the intrusion of the Dartmoor granite, however, has also affected drainage, deflecting the flow of streams from NE-SW along the structural trend to flow down the slopes of the intrusion, creating a radial drainage pattern. The Taw, for Variations in regional uplift from the mid-Pliocene tc the Early Pleistocene in the southwest were investigated by Westaway (2010), who inferred an uplift history of southwest England using data from marine and fluvial terraces and karstic localities. He suggested that a systematic E-W decrease in regional uplift is due to lateral variation in crustal properties and that this is then related to the amount of uplift, incision and thus river-terrace formation. Uplift was modelled by
Figure 25. Drainage patterns in Devon showing radial drainage from Dartmoor and short north coast river: reflecting regional dip. Most of the rivers in Devon flow from north to south (Fig. 25), reflecting the overall regional dip. The high ground formed by the intrusion of the Dartmoor granite, however, has also affected drainage, deflecting the flow of streams from NE-SW along the structural trend to flow down the slopes of the intrusion, creating a radial drainage pattern. The Taw, for Variations in regional uplift from the mid-Pliocene tc the Early Pleistocene in the southwest were investigated by Westaway (2010), who inferred an uplift history of southwest England using data from marine and fluvial terraces and karstic localities. He suggested that a systematic E-W decrease in regional uplift is due to lateral variation in crustal properties and that this is then related to the amount of uplift, incision and thus river-terrace formation. Uplift was modelled by
Figure 26. Brampford Speke. The Church sits on the bigher ground of River Terrace 4 (BGS nomenclature). Terrace 4 is separated by Permian sandstones from the lower terraces and the floodplain (photograph J.A. Bennett).
Figure 26. Brampford Speke. The Church sits on the bigher ground of River Terrace 4 (BGS nomenclature). Terrace 4 is separated by Permian sandstones from the lower terraces and the floodplain (photograph J.A. Bennett).
Figure 27. Dawlish cliffs. Channel structures in the Exe gravels above Permian bedrock. (photograph P.L. Gibbard).
Figure 27. Dawlish cliffs. Channel structures in the Exe gravels above Permian bedrock. (photograph P.L. Gibbard).
Figure 28. Diagrammatic reconstruction of coastal and offshore conditions of the Exe-Teign River, south Devon, about 9,500 years BP (after Clarke, 1970).
Figure 28. Diagrammatic reconstruction of coastal and offshore conditions of the Exe-Teign River, south Devon, about 9,500 years BP (after Clarke, 1970).
Figure 29. Evidence for earlier sea levels around Devon's coast: raised-beach deposits, drowned forests and offshore clifflines. Adapted from Campbell et al. (1998) and Cove (2007).
Figure 29. Evidence for earlier sea levels around Devon's coast: raised-beach deposits, drowned forests and offshore clifflines. Adapted from Campbell et al. (1998) and Cove (2007).
in a disturbed silty matrix. The midden also contains charcoal, animal bone, flint artefacts, and remains of tree roots. Although both Rogers (1946) and Churchill (1965) argued that the midden was formed at or near the contemporary high-water mark, the more comprehensive palaeoenvironmental studies of Balaam et al. (1987), including analyses of pollen, insects and molluscs, showed that it accumulated in a freshwater/ terrestrial (woodland) environment, a short distance from the high-water mark. Charcoal and bone from the midden have yielded radiocarbon dates ranging between about 6.1 and 7.0 ka “C BP, and the base and top of the peat separating the midden from the upper clay have been dated as about 5.7 to 5.2 ka MC BP respectively. The discrepancy between these dates and Churchill’s date of about 6.5 ka “C BP for this peat is unexplained. Wood from tree roots and stumps in the peat gave three dates of about 5.0, 5.6 and 6.1 ka “C BP (see Stephens,1998 for further discussion). 0 pw lf Deere: cm owercien: ‘iced aedia~wavrnllensomcd in conjunction with coastal geomorphological processes, including the formation and shoreward movement of the shingle bar known locally as the ‘Pebble Ridge’ and/or its precursors. This feature, 3 km long and up to 9 m high, consists of well-rounded sandstone cobbles and boulders derived partly (perhaps largely) from erosion of the raised beach referred to earlier, and its continuing northward movement is a matter of observation and historical record (as is its longshore growth from Sandy Mere to near Appledore since about 1750).
in a disturbed silty matrix. The midden also contains charcoal, animal bone, flint artefacts, and remains of tree roots. Although both Rogers (1946) and Churchill (1965) argued that the midden was formed at or near the contemporary high-water mark, the more comprehensive palaeoenvironmental studies of Balaam et al. (1987), including analyses of pollen, insects and molluscs, showed that it accumulated in a freshwater/ terrestrial (woodland) environment, a short distance from the high-water mark. Charcoal and bone from the midden have yielded radiocarbon dates ranging between about 6.1 and 7.0 ka “C BP, and the base and top of the peat separating the midden from the upper clay have been dated as about 5.7 to 5.2 ka MC BP respectively. The discrepancy between these dates and Churchill’s date of about 6.5 ka “C BP for this peat is unexplained. Wood from tree roots and stumps in the peat gave three dates of about 5.0, 5.6 and 6.1 ka “C BP (see Stephens,1998 for further discussion). 0 pw lf Deere: cm owercien: ‘iced aedia~wavrnllensomcd in conjunction with coastal geomorphological processes, including the formation and shoreward movement of the shingle bar known locally as the ‘Pebble Ridge’ and/or its precursors. This feature, 3 km long and up to 9 m high, consists of well-rounded sandstone cobbles and boulders derived partly (perhaps largely) from erosion of the raised beach referred to earlier, and its continuing northward movement is a matter of observation and historical record (as is its longshore growth from Sandy Mere to near Appledore since about 1750).
Figure 31. Schematic representations of changes in vegetation on the higher slopes of northern Dartmoor between 7,700 and 6,300 years BP: upper and lower panels, respectively (after Caseldine and Hatton, 1993).
Figure 31. Schematic representations of changes in vegetation on the higher slopes of northern Dartmoor between 7,700 and 6,300 years BP: upper and lower panels, respectively (after Caseldine and Hatton, 1993).
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