| Computer Code: |
RKM |
Preferred Map Code: |
RkM |
| Status Code: |
Full |
| Age range: |
Holkerian Substage (CQ)
— Holkerian Substage (CQ) |
| Lithological Description: |
A dark to pale olive-and blue-grey, calcareous, bioturbated mudstone, interbedded with dark, laminated, micromicaceous, calcareous siltstones andsporadic fine-grained, grey-blue packstones and wackestones. |
| Definition of Lower Boundary: |
The base of the first mudstone above the characteristic pale noduliferous wackestones of the Hodderense Limestone Formation. |
| Definition of Upper Boundary: |
Taken at the base of the lowest packstone of the Pendleside Limestone Formation with less than 50% interbedded mudstone. |
| Thickness: |
Up to 100 m thick. |
| Geographical Limits: |
Limited to the southern part of the Craven Basin; absent north of the Clitheroe (SD82 44) and Whitwell (SD64 47) anticlines. |
| Parent Unit: |
Pendleside Limestone Formation (PDL)
|
| Previous Name(s): |
Rad Brook Beds [Obsolete Name and Code: Use RKM]
(-4864)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Pendle Hill, stream section in Rad Brook, 2 km east of Worston: Complete section is exposed. Riley, 1990. |
| 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. |
| Metcalfe, I, 1981. Conodont zonation and correlation of the Dinantian and early Namurian strata of the Craven Lowlands of Northern England. Institute of Geological Sciences, Report No. 80/10, p.1-70. |
| 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) |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E067
|
