King Edward - locality, Cainozoic of north-east Scotland: Difference between revisions

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'''From: Merritt, J W, Auton, C A, Connell, E R, Hall, A M, and Peacock, J D. 2003. [[Cainozoic geology and landscape evolution of north-east Scotland. Memoir of the British Geological Survey, sheets 66E, 67, 76E, 77, 86E, 87W, 87E, 95, 96W, 96E and 97 (Scotland)|Cainozoic geology and landscape evolution of north-east Scotland]]. Memoir of the British Geological Survey, sheets 66E, 67, 76E, 77, 86E, 87W, 87E, 95, 96W, 96E and 97 (Scotland).'''
{{CGS}}
 
__FORCETOC__
= King Edward =
= King Edward =
King Edward (NJ 722 561), midway between Turriff and Banff (P915375), is a long recognised locality for the presence there of a Quaternary marine shell bed containing whole arctic marine shells beneath dark grey shelly till (Jamieson, 1866; Sutherland, 1984c). Opinion has been divided over the origin of the shell bed. The state of preservation of the shells and the extent of the shell bed led to the view that this was an in situ marine deposit (Jamieson, 1866; Sutherland, 1981). Alternatively, the intimate association of the shell bed with shelly till led others to consider it to be a glacial raft or rafts (Read, 1923; Peacock and Merritt, 1997).
[[File:P915375.png|thumbnail|Glacial and glaciofluvial features and the distribution of glacigenic deposits on Sheet 86E Turriff. P915375.]]
King Edward (NJ 722 561), midway between Turriff and Banff [[Media:P915375.png|(P915375)]], is a long recognised locality for the presence there of a Quaternary marine shell bed containing whole arctic marine shells beneath dark grey shelly till (Jamieson, 1866; Sutherland, 1984c). Opinion has been divided over the origin of the shell bed. The state of preservation of the shells and the extent of the shell bed led to the view that this was an in situ marine deposit (Jamieson, 1866; Sutherland, 1981). Alternatively, the intimate association of the shell bed with shelly till led others to consider it to be a glacial raft or rafts (Read, 1923; Peacock and Merritt, 1997).


Jamieson gave details of a section beside the Burn of King Edward about 100 m south-west of the old bridge over the Banff–Turriff road in a series of papers spanning almost 50 years (Jamieson, 1858, 1865, 1866, 1906). Today the section is obscured and forested. The upper part comprised up to 8 m of coarse glaciofluvial gravel penetrated by ice-wedge casts. It cropped out along the sides of the burn and its tributaries below high terraces (Read, 1923; Sutherland, 1984c). Below the gravel lay up to 9 m of dark grey pebbly mud, with striated shells towards its base. This diamicton, here named the '''Castleton Member '''of the Whitehills Glacigenic Formation (Castleton Formation of Sutherland, 1999), is typical of the shelly till found widely in the King Edward area (Read, 1923). The base of the section revealed a thin (60 cm thick) layer of brown shelly sand interstratified with more than 3 m of stoneless dark grey silt. The silt contained arctic shells in a crushed and decayed state, but apparently in situ. Jamieson regarded the lowermost shelly silt as representing a marine submergence under arctic conditions that occurred prior to glaciation of the area.
Jamieson gave details of a section beside the Burn of King Edward about 100 m south-west of the old bridge over the Banff–Turriff road in a series of papers spanning almost 50 years (Jamieson, 1858, 1865, 1866, 1906). Today the section is obscured and forested. The upper part comprised up to 8 m of coarse glaciofluvial gravel penetrated by ice-wedge casts. It cropped out along the sides of the burn and its tributaries below high terraces (Read, 1923; Sutherland, 1984c). Below the gravel lay up to 9 m of dark grey pebbly mud, with striated shells towards its base. This diamicton, here named the '''Castleton Member '''of the Whitehills Glacigenic Formation (Castleton Formation of Sutherland, 1999), is typical of the shelly till found widely in the King Edward area (Read, 1923). The base of the section revealed a thin (60 cm thick) layer of brown shelly sand interstratified with more than 3 m of stoneless dark grey silt. The silt contained arctic shells in a crushed and decayed state, but apparently in situ. Jamieson regarded the lowermost shelly silt as representing a marine submergence under arctic conditions that occurred prior to glaciation of the area.


Recent excavation of a river bank 200 m south-east of the original locality (NJ 7236 5604) has confirmed the general succession of terrace gravel resting on dark grey muddy diamicton. The latter rested on over 6 m of intercalated brown sand, grey silt and mud, and dark grey muddy diamicton. Shell fragments occur in varying concentrations and states of preservation throughout these layers. Whole shells, including specimens of ''Lunatia pallida ''and valves of ''Arctica islandica ''and ''Macoma balthica ''were recovered from a sand layer at a depth of 12 m (<u>Table A1.4</u>). The base of the mud sequence was not seen, but a pit beneath the adjacent floodplain of the Burn (at NJ 7234 5602) showed that it rests on coarse glaciofluvial gravel and on bedrock. Although not conclusive evidence, the presence of disturbed contorted and steeply dipping beds is strongly suggestive of glacial disturbance, possibly rafting.
Recent excavation of a river bank 200 m south-east of the original locality (NJ 7236 5604) has confirmed the general succession of terrace gravel resting on dark grey muddy diamicton. The latter rested on over 6 m of intercalated brown sand, grey silt and mud, and dark grey muddy diamicton. Shell fragments occur in varying concentrations and states of preservation throughout these layers. Whole shells, including specimens of ''Lunatia pallida ''and valves of ''Arctica islandica ''and ''Macoma balthica ''were recovered from a sand layer at a depth of 12 m (see table below). The base of the mud sequence was not seen, but a pit beneath the adjacent floodplain of the Burn (at NJ 7234 5602) showed that it rests on coarse glaciofluvial gravel and on bedrock. Although not conclusive evidence, the presence of disturbed contorted and steeply dipping beds is strongly suggestive of glacial disturbance, possibly rafting.
 
{| border="1" class="wikitable"
! Modern Name*||Jamieson (1865)||Gardenstown/Gamrie||King Edward
|-
| | ''Antalis entalis''
| | ''Dentalium entalis''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Amauropsis islandica''
| | ''Natica islandica''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Aporrhais pes-pelicani''
| | ''Aporrhais pes-pelicani''
| | <div align="right">&nbsp;</div>
| | <div align="right">x</div>
 
|-
| | ''Boreotrophon clathratus''
| | ''Trophon clathratus''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''B. clathratus var. gunneri''
| | ''T. clathratus var. gunneri''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''B. truncatus''
| | ''Trophon truncates''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Buccinum undatum''
| | ''Buccinum undatum''
| | <div align="right">x</div>
| | <div align="right">&nbsp;</div>
 
|-
| | ''Colus gracilis''
| style="vertical-align:middle;" rowspan="2" | ''Fusus propinquus''
| style="vertical-align:middle;" rowspan="2" |<div align="right">x</div>
| style="vertical-align:middle;" rowspan="2" |<div align="right">x</div>
 
|-
| | ''C. howsei''
 
|-
| | ''Epitonium greenlandicum''
| | ''Scalaria groenlandica''
| | <div align="right">&nbsp;</div>
| | <div align="right">x</div>
 
|-
| | ''Lacuna vincta''
| | ''Lacuna divaricata''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Oenopota pyramidalis''
| | ''Mangelia pyramidalis''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''O. turricula''
| | ''Mangelia turricula''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Polinices nanus''
| | ''Natica marochiensis''
| | <div align="right">&nbsp;</div>
| | <div align="right">x</div>
 
|-
| | ''P. pallida''
| | ''Natica pallida''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Tectonatica clausa''
| | ''Natica affinis''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Tachyrhyncus reticulata''
| | ''Mesalia reticulata''
| | <div align="right">&nbsp;</div>
| | <div align="right">x</div>
 
|-
| | ''Turritella communis''
| | ''Turritella ungulina''
| | <div align="right">&nbsp;</div>
| | <div align="right">x</div>
 
|-
| | ''Tectura virginea''
| | ''Tectura virginea''
| | <div align="right">x</div>
| | <div align="right">&nbsp;</div>
 
|-
| | ''Acanthocardia echinata''
| | ''Cardium echinata''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Anomia ephippium''
| | ''Anomia ephippium''
| | <div align="right">x</div>
| | <div align="right">&nbsp;</div>
 
|-
| | ''Arctica islandica''
| | ''Cyprina islandica''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Macoma balthica''
| | ''Tellina balthica''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''M. calcarea''
| | ''T. proxima''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Mya truncata''
| | ''Mya truncata''
| | <div align="right">&nbsp;</div>
| | <div align="right">x</div>
 
|-
| | ''Mytilus edulis''
| | ''Mytilus edulis''
| | <div align="right">x</div>
| | <div align="right">&nbsp;</div>
 
|-
| | ''Serripes groenlandicus''
| | ''Cardium groenlandicum''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''Spisula elliptica''
| | ''Mactra solida ''var. ''elliptica''
| | <div align="right">x</div>
| | <div align="right">&nbsp;</div>
 
|-
| | ''Tridonta borealis''
| | ''Astarte borealis''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| | ''T. montagui''
| | ''Astarte compressa''
| | <div align="right">x</div>
| | <div align="right">&nbsp;</div>
 
|-
| | ''Yoldia limatula''
| | ''Leda limatula''
| | <div align="right">&nbsp;</div>
| | <div align="right">x</div>
 
|-
| | ''Yoldiella lucida''
| | ''Leda lucida''
| | <div align="right">&nbsp;</div>
| | <div align="right">x</div>
 
|-
| | ''Zirphaea crispata''
| | ''Pholas crispata''
| | <div align="right">x</div>
| | <div align="right">x</div>
 
|-
| colspan="5"|*For authors of species see Lubinsky (1980); Macpherson (1971) and Smith and Heppell (1991)
|-
| colspan="5"| The bivalve ''Timoclea ovata ''has been reported from Gardenstown/Gamrie (Peacock in Sutherland 1993b).
|-
|}


Jamieson (1865) noted that the faunas from King Edward and Gardenstown (see below) are similar. He tabulated the then known modern distributions in terms of those living:
Jamieson (1865) noted that the faunas from King Edward and Gardenstown (see below) are similar. He tabulated the then known modern distributions in terms of those living:
# on the British coast
# on the British coast
# south of Britain
# south of Britain
Line 14: Line 220:
# on the east coast of North America
# on the east coast of North America
# in the north Pacific.
# in the north Pacific.
Item (3) unfortunately gives a misleading ‘cold’ impression because ‘within the Arctic Circle’ includes the coast of Norway with its boreal fauna (Zenkevitch, 1963). Of the shells in Jamieson’s list, only two (''Tachyrhynchus reticulata ''and ''Serripes greenlandicus'') can be classed as truly arctic to subarctic. Another (''Yoldia limatula'') is an American species that may be confused with the arctic to subarctic ''Y. hyperborea ''(Ockelmann, 1954). Excepting these arctic species, a deep-water taxon (''Yoldiella lucida'') and two boreal taxa (''Polinices nanus ''and ''Turritella communis''), all the molluscs listed in Table P915355 have been recorded in the Late-glacial (Windermere) Interstadial (13 000–11 000 BP) Clyde Beds of western Scotland (Smith et al., 1904). The fauna may thus be taken as generally of non-arctic, interstadial, offshore aspect.


It seems likely that the shell-bearing sands and muds at King Edward are glacially transported rafts within a sequence of glacial deposits derived largely from the bed of the Moray Firth (see Chapter 8; Whitehills Glacigenic Formation). King Edward lies only 1 km north-west of Plaidy (Map P915375) where a large erratic of Oxfordian mudstone was worked in the 19th century (Jamieson, 1859). Other shell-bearing marine deposits previously thought to be in situ (Sutherland, 1981) have since been shown to be erratic masses, for example at Clava (Merritt, 1992b), Gardenstown (Peacock and Merritt, 1997) and the Boyne Limestone Quarry (Peacock and Merritt, 2000a).
Item  3.  unfortunately gives a misleading ‘cold’ impression because ‘within the Arctic Circle’ includes the coast of Norway with its boreal fauna (Zenkevitch, 1963). Of the shells in Jamieson’s list, only two (''Tachyrhynchus reticulata ''and ''Serripes greenlandicus'') can be classed as truly arctic to subarctic. Another (''Yoldia limatula'') is an American species that may be confused with the arctic to subarctic ''Y. hyperborea ''(Ockelmann, 1954). Excepting these arctic species, a deep-water taxon (''Yoldiella lucida'') and two boreal taxa (''Polinices nanus ''and ''Turritella communis''), all the molluscs listed in the table above have been recorded in the Late-glacial (Windermere) Interstadial (13 000–11 000 BP) Clyde Beds of western Scotland (Smith et al., 1904). The fauna may thus be taken as generally of non-arctic, interstadial, offshore aspect.
 
[[File:P915290.png|left|thumbnail|Devensian–Weichselian events in Britain and south-west Fennoscandia. P915290.]]
It seems likely that the shell-bearing sands and muds at King Edward are glacially transported rafts within a sequence of glacial deposits derived largely from the bed of the Moray Firth. King Edward lies only 1 km north-west of Plaidy [[Media:P915375.png|(P915375)]] where a large erratic of Oxfordian mudstone was worked in the 19th century (Jamieson, 1859). Other shell-bearing marine deposits previously thought to be in situ (Sutherland, 1981) have since been shown to be erratic masses, for example at Clava (Merritt, 1992b), Gardenstown (Peacock and Merritt, 1997) and the Boyne Limestone Quarry (Peacock and Merritt, 2000a).


[[File:P915347.png|thumbnail|Correlation of lithostratigraphical units in north-east Scotland. P915347.]]
At King Edward, amino-acid ratios between 0.073 and 0.095 (mean value 0.078 + 0.010) have been obtained from five ''Arctica ''shells collected from till at a site 200 m north-east of Jamieson’s section. Uncalibrated AMS radiocarbon ages of greater than 44 200 BP (AA–1323) and greater than 41 500 BP (AA–1324) are reported on two of the analysed shells (Miller et al., 1987). On this basis the shells in the Castleton Member of the Whitehills Glacigenic Formation have been assigned to the interval between 40 and 80 ka BP (Miller et al., 1987). This age is consistent with the faunal evidence at King Edward of interstadial conditions. It appears on current evidence that these marine muds and sands were originally deposited on the floor of the Inner Moray Firth during OIS 4 or 3.
At King Edward, amino-acid ratios between 0.073 and 0.095 (mean value 0.078 + 0.010) have been obtained from five ''Arctica ''shells collected from till at a site 200 m north-east of Jamieson’s section. Uncalibrated AMS radiocarbon ages of greater than 44 200 BP (AA–1323) and greater than 41 500 BP (AA–1324) are reported on two of the analysed shells (Miller et al., 1987). On this basis the shells in the Castleton Member of the Whitehills Glacigenic Formation have been assigned to the interval between 40 and 80 ka BP (Miller et al., 1987). This age is consistent with the faunal evidence at King Edward of interstadial conditions. It appears on current evidence that these marine muds and sands were originally deposited on the floor of the Inner Moray Firth during OIS 4 or 3.
The timing of the glacial phase or phases that emplaced the rafts of marine sediment is uncertain. While some tills and rafts derived from the Moray Firth are thought to have been deposited during the Late Devensian (Merritt, 1992b), the possibility remains that some were transported during a Middle Devensian glacial phase equivalent to the Norwegian Skjonghelleren glaciation (P915290). The dark grey shelly tills of the Whitehills Glacigenic Formation around King Edward are covered in places, or merge upwards into, red-brown sandy till (Read, 1923). The latter is probably laterally equivalent to the Crovie Till Formation at Gardenstown and the Old Hythe Till Formation at the Boyne Limestone Quarry, but the exact age of all these units is unclear (P915347).
 
The timing of the glacial phase or phases that emplaced the rafts of marine sediment is uncertain. While some tills and rafts derived from the Moray Firth are thought to have been deposited during the Late Devensian (Merritt, 1992b), the possibility remains that some were transported during a Middle Devensian glacial phase equivalent to the Norwegian Skjonghelleren glaciation [[Media:P915290.png|(P915290)]]. The dark grey shelly tills of the Whitehills Glacigenic Formation around King Edward are covered in places, or merge upwards into, red-brown sandy till (Read, 1923). The latter is probably laterally equivalent to the Crovie Till Formation at Gardenstown and the Old Hythe Till Formation at the Boyne Limestone Quarry, but the exact age of all these units is unclear [[Media:P915347.png|(P915347)]].
 
== References ==
== References ==
[[References, Cainozoic of north-east Scotland|Full reference list]]
[[References, Cainozoic of north-east Scotland|Full reference list]]

Latest revision as of 17:00, 31 January 2018

Merritt, J W, Auton, C A, Connell, E R, Hall, A M, and Peacock, J D. 2003. Cainozoic geology and landscape evolution of north-east Scotland. Memoir of the British Geological Survey, sheets 66E, 67, 76E, 77, 86E, 87W, 87E, 95, 96W, 96E and 97 (Scotland).

Contributors: J F Aitken, D F Ball, D Gould, J D Hansom, R Holmes, R M W Musson and M A Paul.

King Edward

Glacial and glaciofluvial features and the distribution of glacigenic deposits on Sheet 86E Turriff. P915375.

King Edward (NJ 722 561), midway between Turriff and Banff (P915375), is a long recognised locality for the presence there of a Quaternary marine shell bed containing whole arctic marine shells beneath dark grey shelly till (Jamieson, 1866; Sutherland, 1984c). Opinion has been divided over the origin of the shell bed. The state of preservation of the shells and the extent of the shell bed led to the view that this was an in situ marine deposit (Jamieson, 1866; Sutherland, 1981). Alternatively, the intimate association of the shell bed with shelly till led others to consider it to be a glacial raft or rafts (Read, 1923; Peacock and Merritt, 1997).

Jamieson gave details of a section beside the Burn of King Edward about 100 m south-west of the old bridge over the Banff–Turriff road in a series of papers spanning almost 50 years (Jamieson, 1858, 1865, 1866, 1906). Today the section is obscured and forested. The upper part comprised up to 8 m of coarse glaciofluvial gravel penetrated by ice-wedge casts. It cropped out along the sides of the burn and its tributaries below high terraces (Read, 1923; Sutherland, 1984c). Below the gravel lay up to 9 m of dark grey pebbly mud, with striated shells towards its base. This diamicton, here named the Castleton Member of the Whitehills Glacigenic Formation (Castleton Formation of Sutherland, 1999), is typical of the shelly till found widely in the King Edward area (Read, 1923). The base of the section revealed a thin (60 cm thick) layer of brown shelly sand interstratified with more than 3 m of stoneless dark grey silt. The silt contained arctic shells in a crushed and decayed state, but apparently in situ. Jamieson regarded the lowermost shelly silt as representing a marine submergence under arctic conditions that occurred prior to glaciation of the area.

Recent excavation of a river bank 200 m south-east of the original locality (NJ 7236 5604) has confirmed the general succession of terrace gravel resting on dark grey muddy diamicton. The latter rested on over 6 m of intercalated brown sand, grey silt and mud, and dark grey muddy diamicton. Shell fragments occur in varying concentrations and states of preservation throughout these layers. Whole shells, including specimens of Lunatia pallida and valves of Arctica islandica and Macoma balthica were recovered from a sand layer at a depth of 12 m (see table below). The base of the mud sequence was not seen, but a pit beneath the adjacent floodplain of the Burn (at NJ 7234 5602) showed that it rests on coarse glaciofluvial gravel and on bedrock. Although not conclusive evidence, the presence of disturbed contorted and steeply dipping beds is strongly suggestive of glacial disturbance, possibly rafting.

Modern Name* Jamieson (1865) Gardenstown/Gamrie King Edward
Antalis entalis Dentalium entalis
x
x
Amauropsis islandica Natica islandica
x
x
Aporrhais pes-pelicani Aporrhais pes-pelicani
 
x
Boreotrophon clathratus Trophon clathratus
x
x
B. clathratus var. gunneri T. clathratus var. gunneri
x
x
B. truncatus Trophon truncates
x
x
Buccinum undatum Buccinum undatum
x
 
Colus gracilis Fusus propinquus
x
x
C. howsei
Epitonium greenlandicum Scalaria groenlandica
 
x
Lacuna vincta Lacuna divaricata
x
x
Oenopota pyramidalis Mangelia pyramidalis
x
x
O. turricula Mangelia turricula
x
x
Polinices nanus Natica marochiensis
 
x
P. pallida Natica pallida
x
x
Tectonatica clausa Natica affinis
x
x
Tachyrhyncus reticulata Mesalia reticulata
 
x
Turritella communis Turritella ungulina
 
x
Tectura virginea Tectura virginea
x
 
Acanthocardia echinata Cardium echinata
x
x
Anomia ephippium Anomia ephippium
x
 
Arctica islandica Cyprina islandica
x
x
Macoma balthica Tellina balthica
x
x
M. calcarea T. proxima
x
x
Mya truncata Mya truncata
 
x
Mytilus edulis Mytilus edulis
x
 
Serripes groenlandicus Cardium groenlandicum
x
x
Spisula elliptica Mactra solida var. elliptica
x
 
Tridonta borealis Astarte borealis
x
x
T. montagui Astarte compressa
x
 
Yoldia limatula Leda limatula
 
x
Yoldiella lucida Leda lucida
 
x
Zirphaea crispata Pholas crispata
x
x
*For authors of species see Lubinsky (1980); Macpherson (1971) and Smith and Heppell (1991)
The bivalve Timoclea ovata has been reported from Gardenstown/Gamrie (Peacock in Sutherland 1993b).

Jamieson (1865) noted that the faunas from King Edward and Gardenstown (see below) are similar. He tabulated the then known modern distributions in terms of those living:

  1. on the British coast
  2. south of Britain
  3. within the Arctic Circle
  4. on the east coast of North America
  5. in the north Pacific.

Item 3. unfortunately gives a misleading ‘cold’ impression because ‘within the Arctic Circle’ includes the coast of Norway with its boreal fauna (Zenkevitch, 1963). Of the shells in Jamieson’s list, only two (Tachyrhynchus reticulata and Serripes greenlandicus) can be classed as truly arctic to subarctic. Another (Yoldia limatula) is an American species that may be confused with the arctic to subarctic Y. hyperborea (Ockelmann, 1954). Excepting these arctic species, a deep-water taxon (Yoldiella lucida) and two boreal taxa (Polinices nanus and Turritella communis), all the molluscs listed in the table above have been recorded in the Late-glacial (Windermere) Interstadial (13 000–11 000 BP) Clyde Beds of western Scotland (Smith et al., 1904). The fauna may thus be taken as generally of non-arctic, interstadial, offshore aspect.

Devensian–Weichselian events in Britain and south-west Fennoscandia. P915290.

It seems likely that the shell-bearing sands and muds at King Edward are glacially transported rafts within a sequence of glacial deposits derived largely from the bed of the Moray Firth. King Edward lies only 1 km north-west of Plaidy (P915375) where a large erratic of Oxfordian mudstone was worked in the 19th century (Jamieson, 1859). Other shell-bearing marine deposits previously thought to be in situ (Sutherland, 1981) have since been shown to be erratic masses, for example at Clava (Merritt, 1992b), Gardenstown (Peacock and Merritt, 1997) and the Boyne Limestone Quarry (Peacock and Merritt, 2000a).

Correlation of lithostratigraphical units in north-east Scotland. P915347.

At King Edward, amino-acid ratios between 0.073 and 0.095 (mean value 0.078 + 0.010) have been obtained from five Arctica shells collected from till at a site 200 m north-east of Jamieson’s section. Uncalibrated AMS radiocarbon ages of greater than 44 200 BP (AA–1323) and greater than 41 500 BP (AA–1324) are reported on two of the analysed shells (Miller et al., 1987). On this basis the shells in the Castleton Member of the Whitehills Glacigenic Formation have been assigned to the interval between 40 and 80 ka BP (Miller et al., 1987). This age is consistent with the faunal evidence at King Edward of interstadial conditions. It appears on current evidence that these marine muds and sands were originally deposited on the floor of the Inner Moray Firth during OIS 4 or 3.

The timing of the glacial phase or phases that emplaced the rafts of marine sediment is uncertain. While some tills and rafts derived from the Moray Firth are thought to have been deposited during the Late Devensian (Merritt, 1992b), the possibility remains that some were transported during a Middle Devensian glacial phase equivalent to the Norwegian Skjonghelleren glaciation (P915290). The dark grey shelly tills of the Whitehills Glacigenic Formation around King Edward are covered in places, or merge upwards into, red-brown sandy till (Read, 1923). The latter is probably laterally equivalent to the Crovie Till Formation at Gardenstown and the Old Hythe Till Formation at the Boyne Limestone Quarry, but the exact age of all these units is unclear (P915347).

References

Full reference list