Computer Code: |
AST |
Preferred Map Code: |
AST |
Status Code: |
Pending Upgrade |
Age range: |
Homerian Age (SH)
— Gorstian Age (SG) |
Lithological Description: |
Grey thickly bedded (blocky) mudstone, commonly bioturbated. |
Definition of Lower Boundary: |
Upwards change in lithology for grey well-bedded (shaly) mudstone to grey thickly bedded (blocky) mudstone. |
Definition of Upper Boundary: |
See Bishopsmoat Beds, Lower. |
Thickness: |
c.100m (lateral variations from about 100 - 275m). |
Geographical Limits: |
Not defined. |
Parent Unit: |
Not Applicable (-)
|
Previous Name(s): |
Aston Beds [Obsolete Name and Code: Use AST]
(-31)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Area |
Sheet 165. |
Reference(s): |
Allender, R. 1959. On the stratigraphy and structure of an area of Ludlowian and Lower Downtonian near Bishops Castle, Shropshire. Unpublished Ph.D. Thesis, University of Wales. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E165
|