Computer Code: |
BED |
Preferred Map Code: |
Bed |
Status Code: |
Index Level |
Age range: |
Chadian Substage (CI)
— Asbian Substage (CR) |
Lithological Description: |
[Obsolete: use FANT, FRFA, LGY, MEST, PANT, PDW] Purple and green shales, interstratified with bands of purplish or grey limestone, red, yellow and white sandstone and red marl. Conglomerates locally. |
Definition of Lower Boundary: |
Unconformable on underlying rocks (Silurian/Ordovician). |
Definition of Upper Boundary: |
Base of overlying dark, bedded, fine-grained limestones or sandstones (Llanarmon Limestone, Llwyn-y-Fran Sandstone, Ty-nant Limestone). |
Thickness: |
To about 100m |
Geographical Limits: |
See extents of replacment terms: Lligwy Sandstone; Menai Straits; Ffernant; Penbedw; Fron Fawr; Pant formations. |
Parent Unit: |
none recorded or not applicable
|
Previous Name(s): |
Old Red Sandstone [Obsolete Name and Code: Use BOBC, BED]
(-3838)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
none recorded or not applicable |
Reference(s): |
Waters, C N, Waters, R A, Barclay, W J, and Davies, J R. 2009. Lithostratigraphical framework for Carboniferous successions of Southern Great Britain (Onshore). British Geological Survey Research Report, RR/09/01. 184pp. |
Strahan, A. 1890. The Geology of the Neighbourhoods of Flint, Mold and Ruthin. Memoir of the Geological Survey, Sheet 79SE (England and Wales). |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E121
E137
|