| Computer Code: |
WML |
Preferred Map Code: |
WmL |
| Status Code: |
Full |
| Age range: |
Chadian Substage (CI)
— Chadian Substage (CI) |
| Lithological Description: |
Wackestones and packstones, pale blue-grey, thin-bedded, bioclastic, fine-to coarse-grained, graded, often erosive-based and containing intraformational lithoclasts, interbedded with similar amounts of pale blue-grey calcareous mudstone, commonly platy and blocky. |
| Definition of Lower Boundary: |
The base is defined at the base of the first pale blue-grey wackestones of the Whitemore Limestone Member overlying conformably the dark grey mudstones of the Phynis Mudstone Member. |
| Definition of Upper Boundary: |
In the Whitewell Anticline, taken at the base of the dark grey blocky mudstone interbedded with thin wackestones of the Leagram Mudstone Member, overlying conformably the pale blue-grey wackestones and packstones of the Whitemore Limestone Member. In the Slaidburn Anticline, the limestones of the Whitemore Limestone Member are overlain by non-micaceous, laminated mudstones interbedded with laminated calcisiltites of the Hodder Mudstone Formation (undifferentiated). |
| Thickness: |
Up to 80 m thick. |
| Geographical Limits: |
Limited to the Slaidburn (SD 71 53) and Whitewell (SD 64 47) anticlines and the northern limb of the Plantation Farm Anticline (SD 66 43), from the western part of the Craven Basin. |
| Parent Unit: |
Hodder Mudstone Formation (HOM)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Stream section at Whitemore Knott, Whitewell, 1km west of Burholme Bridge: the section includes the base of the member and all but the uppermost 10 m of the member. Riley, 1990. |
| Reference(s): |
| 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) |
| 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. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E067
|
