The BGS Lexicon of Named Rock Units — Result Details

Aston Mudstone Formation

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 (-31)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Sheet 165. 
Reference(s):
Allender, R, Not published. On the stratigraphy and structure of an area of Ludlowian and Lower Downtonian near Bishops Castle, Shropshire. Ph.D. Thesis (1959) University of Wales. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E165