Computer Code: |
ESH |
Preferred Map Code: |
ESH |
Status Code: |
Index Level |
Age range: |
Namurian Stage (CN)
— Namurian Stage (CN) |
Lithological Description: |
[Obsolete: use BSG] Dark grey and grey mudstones with subordinate bands of limestone, ironstone, siliceous sandstone and siltstone, and calcareous siltstone. |
Definition of Lower Boundary: |
Incoming of Cravenoceras leion, or where limestone bands decrease markedly upwards in a mudstone sequence. |
Definition of Upper Boundary: |
Base of lowest significant feldspathic sandstone (Mam Tor Sandstones in type area). |
Thickness: |
Varies greatly, 0 at basin margin, 240m in type area, 370m in Alport Borehole. |
Geographical Limits: |
Central and south Pennines; Peak District; North Staffordshire Basin, Widmerpool Gulf. |
Parent Unit: |
none recorded or not applicable
|
Previous Name(s): |
Edale Shales [Obsolete Name and Code: Use BSG, ESH]
(-1397)
|
Alternative Name(s): |
Bowland Shale Formation
|
Stratotypes: |
Reference Section |
For most of group including base: Duffield Borehole: 0.86 to 405.78m depth:E1a to H1a mudstone resting conformably on Widmerpool Formation: Aitkenhead, 1977. |
Type Area |
Edale, Derbyshire: stream sections detailed on 1:25,000 geological sheet SK18 (Castleton) and in Stevenson and Gaunt, 1971. |
Reference Section |
For most of group including top: Blake Brook, discontinuous stream section (see Aitkenhead et al, 1985, fig 28; measured sections: SK06SE/14,15,16,17). |
Reference Section |
Alport borehole: borehole 20ft to 1099ft (6.09-334.97m): covers base to H2 |
Reference Section |
For full group: Tansley Borehole from 462ft 7ins (140.99m)(base of Ashover Grit) to 962ft 8.5ins (293.43m)(base of Cravenoceras leion Band). Ramsbottom et al, 1962. |
Reference Section |
Edale Borehole: borehole, 0-325ft (99.06m) depth: covers base to E1b |
Reference(s): |
Stevenson, I P and Gaunt, G D, 1971. Geology of the country around Chapel-en-le-Frith. Memoir of the Geological Survey of Great Britain, England and Wales, Sheet 99. |
Ramsbottom, W H C, Rhys, G H and Smith, E G, 1962. Boreholes in the Carboniferous Rocks of the Ashover district, Derbyshire. Bulletin of the Geological Survey of Great Britian, No.19, p.75-142. |
Aitkenhead, N, Chisholm, J I, and Stevenson, I P. 1985. Geology of the country around Buxton, Leek and Bakewell. Memoir of the British Geological Survey, England and Wales Sheet 111. |
Hudson, R G S and Cotton, G, 1946. The Carboniferous rocks of the Edale Anticline, Derbyshire. Quarterly Journal of the Geological Society of London, Vol.101, p.1-34. |
Jackson, J W, 1927. The succession below the Kinderscout Grit in north Derbyshire. Journal of the Manchester Geological Society, Vol.1/1, p.15-33 |
Aitkenhead, N. 1977. The Institute of Geological Sciences borehole at Duffield, Derbyshire. Bulletin of the Geological Survey of Great Britain, No. 59, 1-38. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E123
E142
E141
|