| Computer Code: |
JRSA |
Preferred Map Code: |
JRS |
| Status Code: |
Full |
| Age range: |
Rawtheyan Stage (OW)
— Rawtheyan Stage (OW) |
| Lithological Description: |
Massive greenish or purplish grey, medium-grained volcaniclastic sandstone, poorly sorted but with a weak lamination locally. |
| Definition of Lower Boundary: |
Taken at the base of the tuffaceous sandstone, unconformably overlying the siltstone and limestone sequence of the Norber Formation. |
| Definition of Upper Boundary: |
Taken at the base of overlying siltstone and mudstone of the main part of the Sowerthwaite Siltstone Formation. |
| Thickness: |
40 to 250 m. |
| Geographical Limits: |
Restricted to the Craven Inliers, North Yorkshire. |
| Parent Unit: |
Sowerthwaite Formation (SOW)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Jop Ridding Farm, about 1 km north-east of Austwick [SD 7831 6897]. Arthurton et al., 1988. |
| Reference(s): |
| Millward, D, and Stone, P. 2012. Stratigraphical framework for the Ordovician and Silurian sedimentary strata of northern England and the Isle of Man. British Geological Survey Research Report, RR/12/04. 119pp. |
| 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). |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E060
|
