| Computer Code: |
THTL |
Preferred Map Code: |
ThtL |
| Status Code: |
Full |
| Age range: |
Chadian Substage (CI)
— Chadian Substage (CI) |
| Lithological Description: |
Packstones, wackestones and subordinate grainstones predominantly wavy-bedded, muddy, pale to dark grey, bioclastic and locally cherty, interbedded with variable amounts of dark-grey calcareous mudstone and siltstone. Bioturbation is common. |
| Definition of Lower Boundary: |
Overlies the Chatburn Limestone Group. |
| Definition of Upper Boundary: |
Overlain unconformably by the Hodder Mudstone Formation in the Worston Shale Group. |
| Thickness: |
To 200m |
| Geographical Limits: |
Confined to the Craven Basin of Lancashire and Yorkshire. |
| Parent Unit: |
Clitheroe Limestone Formation (CLL)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Disused quarries 0.85km northwest of Stainton Hall (Arthurton and others, 1988, p.44). Neither base nor top exposed. |
| Reference(s): |
| Hudson, R G S and Dunnington, H V, 1944. The Carboniferous rocks of the Swindon Anticline, Yorkshire. Proceedings of the Geologists' Association, Vol.55, p.195-215. |
| Moseley, F, 1962. The structure of the south-western part of the Sykes Anticline, Bowland, West Yorkshire. Proceedings of the Yorkshire Geological Society, Vol.33, p.287-314. |
| Riley N J. 1990. Stratigraphy of the Worston Shale Group (Dinantian) Craven Basin, north-west England. Proceedings of the Yorkshire Geological Society, Vol. 48, 163-187. |
| Earp, J R, Magraw, D, Poole, E G, Land, D H, and Whiteman, A J. 1961. Geology of the country around Clitheroe and Nelson. Memoir of the Geological Survey of Great Britain, Sheet.68, England and Wales, p. 346. |
| Arthurton, R S, Johnson, E W, and Mundy, D J C. 1988. Geology of the country around Settle. Memoir of the British Geological Survey, Sheet 60 (England and Wales). |
| Wadge, A J et al. 1983. Mineral reconnaissance surveys in the Craven Basin. Institute of Geological Sciences Mineral Reconnaissance Programme Report, Vol.66. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E059
E067
E060
|
