The BGS Lexicon of Named Rock Units — Result Details

Nant Hir Mudstone [Obsolete Name And Code: Use CSW]

Computer Code: NHM Preferred Map Code: notEntered
Status Code: Index Level
Age range: Harnagian Substage (OG) — Harnagian Substage (OG)
Lithological Description: Mudstones and siltstone.
Definition of Lower Boundary: Overlies the Aran Volcanic Group.
Definition of Upper Boundary: Underlies the Cefn Gwyn Tuff.
Thickness: About 1000m
Geographical Limits: none recorded or not applicable
Parent Unit: Not Entered (?)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Nant Hir valley. 
Reference(s):
Bassett, D A, Whittington, H B and Williams, A. 1966. The stratigraphy of the Bala district, Merionethshire. Quarterly Journal of the Geological Society of London, Vol.122, 219-271. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable