Computer Code: |
DTG |
Preferred Map Code: |
notEntered |
Status Code: |
Full |
Age range: |
Lochkovian Age (DO)
— Pragian Age (DP) |
Lithological Description: |
[Obsolete: use FWW]
Red mudstones, red-brown, purple and green sandstones and fish-bearing intraformational conglomerates; some mature soil carbonate horizons, in addition to numerous calcrete glaebule horizons. The lithologies are commonly arranged in fining-upwards cycles. |
Definition of Lower Boundary: |
The lower boundary is placed at top of the Bishop’s Frome (Psammosteus) Limestone Member at the top of the Raglan Mudstone Formation, where overlain by red mudstone of the St Maughans Formation. |
Definition of Upper Boundary: |
The upper boundary is placed at the base of Brownstones Formation and (locally) Senni Formation, where sandstone-dominated sequences begin. The upper boundary is locally placed at top of the Upper Abdon Limestone Member in the Clee Hills. |
Thickness: |
Up to 600 m. |
Geographical Limits: |
Present at crop in the West Midlands, Welsh Borderland, south-east and south-central Wales. |
Parent Unit: |
none recorded or not applicable
|
Previous Name(s): |
Ditton Group
(-5136)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
none recorded or not applicable |
Reference(s): |
Allen, J R L. 1977. Wales and the Welsh Borders. 40-54 in House, M R et al. A correlation of Devonian rocks in the British Isles. Geological Society, London, Special Report No. 7. |
Waters, C N, Smith, K, Hopson, P M, Wilson, D, Bridge, D M, Carney, J N, Cooper, A H, Crofts, R G, Ellison, R A, Mathers, S J, Moorlock, B S P, Scrivener, R C, McMillan, A A, Ambrose, K, Barclay, W J, and Barron, A J M. 2007. Stratigraphical Chart of the United Kingdom: Southern Britain. British Geological Survey, 1 poster. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |