| Computer Code: |
CATP |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Tremadoc Series (O1)
— Tremadoc Series (O1) |
| Lithological Description: |
The formation comprises turbiditic siltstones interbedded with beds and sequences of lithic greywacke sandstone which constitute between 20 and 40 per cent of the succession. The sandstone is fine to medium grained in beds generally 5 to 150 cm thick, but exceptionally up to 5 m. A 4 m thick conglomerate is recorded in Melmerby Beck (Arthurton and Wadge, 1981).
Macrofossils have not been found, but the acritarch microflora indicate a latest Tremadoc age (Cooper and Molyneux, 1990). |
| Definition of Lower Boundary: |
The base is not exposed. |
| Definition of Upper Boundary: |
The contact with the younger Kirkland Mudstone Formation is faulted. |
| Thickness: |
At least 1000 m. |
| Geographical Limits: |
Restricted to the Cross Fell Inlier, to the north of the inferred eastward extension of the Causey Pike Fault: occurs on Catterpallot Hill [NY 638 363], and adjacent streams of Dry Sike [NY 630 370], Hungrigg Sike, Melmerby Beck and Martins Sike. |
| Parent Unit: |
Skiddaw Group (SKG)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
The type area is defined on Catterpallot Hill [NY 638 363] and adjacent streams of Dry Sike, Hungrigg Sike, Martins Sike and Melmerby Beck [NY 620 370]. |
| 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, and Wadge, A J. 1981. Geology of the country around Penrith. Memoir for geological sheet 24. Institute of Geological Sciences, London, HMSO. |
| Burgess, I C, and Wadge, A J. 1974. The geology of the Cross Fell area. Explanation of 1:25 000 Geological Special Sheet comprising parts of sheets NY 53, 62, 63, 64, 71, 72, 73. (London HMSO). 91pp. |
| Cooper, A H, Fortey, N J, Hughes, R A, Molyneux, S G, Moore, R M, Rushton, A W A, Stone, P, Allen, P M, Cooper, D C, Evans, J A, Hirons, S R, and Webb, B C. 2004. The Skiddaw Group of the English Lake District. Memoir of the British Geological Survey. |
| Cooper, A H and Molyneux, S G, 1990. The age and correlation of Skiddaw Group [early Ordovician] sediments in the Cross Fell Inlier [northern England]. Geological Magazine, Vol.127, 147-157. |
| Wadge, A J, 1978.Classification and stratigraphical relationships of the Lower Ordovician Rocks. 68-78 in The Geology of the Lake District (editor F. Moseley). Yorkshire Geological Society, Occasional Publication No.3. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
