| Computer Code: |
PQL |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Chadian Substage (CI)
— Chadian Substage (CI) |
| Lithological Description: |
Packstone and grainstone, clean washed, fine-to coarse-grained, pale grey, with thin to thick, massive and multi-storey beds, wavy bedded and chert with abundant crinoid, algal and pellet grains, interbedded with subordinate dark to brownish grey, calcareous mudstones, platy with bedding planes crowded with brachiopods and ostracods. Many limestones contain intraformational lithoclasts and show erosive bases. Grading and cross-bedding occur, together with high-angle, imbricate shell-lags. |
| Definition of Lower Boundary: |
Conformable passage from poorly exposed dark grey fissile mudstones and packstones of the "Upper Coplow Shales" to packstones and grainstones of the Peach Quarry Limestone Member. |
| Definition of Upper Boundary: |
Gradational passage from the packstones and grainstones into the Waulsortian limestones of the Bellman Limestone Member. |
| Thickness: |
Up to 70m thick. |
| Geographical Limits: |
Lenticular unit restricted to the southern limb of the Clitheroe Anticline (SD 74). |
| Parent Unit: |
Clitheroe Limestone Formation (CLL)
|
| Previous Name(s): |
Peach Quarry Limestone [Obsolete Name and Code: Use PQL]
(-2378)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Road cutting on the A59 Clitheroe By-pass between (SD 7700 4380) and (SD 7685 4392), 3.2 km north-east of Clitheroe Castle. The base and top of the member are not exposed. Riley, 1990. |
| Reference Section |
Peach Quarry, 1.7 km north-east of Clitheroe Castle, shows a deteriorating section with strata dipping at 40 degrees to the southeast. Riley, 1990. |
| Reference Section |
Upper part of member: Northern side of Bellman Quarry (SD 7600 4290), in the old tramway cutting 2.25 km north-east of Clitheroe Castle. |
| Reference(s): |
| 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, pp.346. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E067
E068
|
