The BGS Lexicon of Named Rock Units — Result Details

Aughnacloy Sandstone Formation

Computer Code: ACSF Preferred Map Code: notEntered
Status Code: Pending Upgrade
Age range: Holkerian Substage (CQ) — Asbian Substage (CR)
Lithological Description: A pale grey, medium-grained, parallel laminated, calcareous sandstone, which is ooidal in parts, and locally fossiliferous silty mudstone containing brachiopods and corals.
Definition of Lower Boundary: Not seen, but it is assumed to be conformable with the calcareous mudstones and thin interbedded limestones of the underlying Benbulben Shale Formation.
Definition of Upper Boundary: Not seen, but seems to be conformable with the overlying Maydown Limestone Formation.
Thickness: From 160 m - 300 m thick.
Geographical Limits: Counties Armargh and Tyrone, Northern Ireland.
Parent Unit: Tyrone Group (TYRO)
Previous Name(s): Auchnacloy Sandstone Member [Obsolete Name and Code: Use ACSF] (-1300)
Aughnacloy Sandstone Member [Obsolete Name And Code: Use ACSF] (ACS)
Alternative Name(s): none recorded or not applicable
Stratotypes:
none recorded or not applicable
Reference(s):
none recorded or not applicable
1:50K maps on which the lithostratigraphical unit is found, and map code used:
N34 N46