| Computer Code: |
PDL |
Preferred Map Code: |
PdL |
| Status Code: |
Full |
| Age range: |
Holkerian Substage (CQ)
— Asbian Substage (CR) |
| Lithological Description: |
Grey, fine- to coarse-grained, bioclastic, commonly graded, erosive-based and bioturbated cherty packstones, interbedded with wackestone, sporadic intraformational and extraformational limestone conglomerate, and especially in the lower part, dark to pale olive- and blue-grey mudstone (Rad Brook Mudstone Member). Locally dolomitized, especially in the packstones, and rare sandstones. |
| Definition of Lower Boundary: |
In the type section, the base is defined at the base of the first grey mudstone bed lying above the pale olive and blue-grey nodule-bearing wackestones that characterize the Hodderense Limestone Formation. |
| Definition of Upper Boundary: |
The junction with the overlying Bowland Shale Formation is marked by the absence of bioturbation, and by a colour change from pale olive- and blue-grey, to dark blue and black, as mudstones and interbedded limestones become fetid and petroliferous. This colour change commonly corresponds to the entry of limestone breccias. |
| Thickness: |
To 300m |
| Geographical Limits: |
Occurs throughout the Craven Basin, roughly between Lancaster [SD46], Skipton [SD95] and Preston [SD52]. |
| Parent Unit: |
Craven Group (CRAV)
|
| Previous Name(s): |
Pendleside Limestone [Obsolete Name and Code: Use PDL]
(*873)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Reference Section |
Composite section in Cutlers Quarry [SD 6239 4007] and Dale House Quarry [SD 6253 4022] (both disused), about 2.5km northeast of Longridge, Lancashire. Aitkenhead et al.,1992. |
| Reference Section |
Red Syke, Twiston Moor, Lancashire, provides a near-complete section. Earp et al., 1961, p.71 and 91-92. |
| Type Section |
Pendle Hill, Burst Clough, seen on the lower slopes, 0.16km southeast of Angram Green Farm, 1.38km eastsoutheast of Worston. Almost complete section is exposed, together with lower beds of the overlying Bowland Shale Formation. Riley,1990. |
| Reference(s): |
| Parkinson, D, 1926. The faunal succession in the Carboniferous Limestone and Bowland Shales at Clitheroe and Pendle Hill, Lancashire. Quarterly Journal of the Geological Society of London. Volume 82. p.188-249. |
| Parkinson, D, 1936. The Carboniferous succession in the Slaidburn district, Yorkshire. Quarterly Journal of the Geological Society of London. Volume 92. p.294-331. |
| Aitkenhead, N, Bridge, D M, Riley, N J, and Kimbell, S F. 1992. Geology of the country around Garstang. Memoir of the British Geological Survey, Sheet 67 (England and Wales) |
| Gawthorpe, R L. 1987. Tectono-sedimentary evolution of the Bowland Basin, N. England, during the Dinantian. Journal of the Geological Society of London, Vol.144, 44-59. |
| 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, pp.346. |
| 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. |
| Parkinson, D. 1935. The geology and topography of the limestone knolls in Bolland (Bowland), Lancs. and Yorks. Proceedings of the Geologists' Association, Vol.46, 97-120. |
| 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). |
| Fewtrell, M D and Smith, D G, 1980. Revision of the Dinantian stratigraphy of the Craven Basin, N. England. Geological Magazine, Vol.117, p.37-49. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E067
E068
E059
E060
E069
|
