The BGS Lexicon of Named Rock Units — Result Details

Tyrone Group

Computer Code: TYRO Preferred Map Code: TYRO
Status Code: Full
Age range: Courceyan Substage (CF) — Asbian Substage (CR)
Lithological Description: Mixed sequence of thin basal (red-bed) clastics, marine limestones (with mud mounds) and shales/mudstones; thin deltaic horizons. NOTE: Reference Sections: see component formations: Daltry, Glancar, Ballyshannon, Termon River Limestone, Tubbrid, Mullaghmore, Bin Mountain, Claragh Sandstone, Benbulben, Bundoran, Keeneghan Shale and Drumchorick Siltstone formations.
Definition of Lower Boundary: Unconformable on metamorphic basement or Courceyan Omagh Sandstone Group.
Definition of Upper Boundary: Overlain disconformably by predominantly shale sequence of the Leitrim Group.
Thickness: To 2400m
Geographical Limits: The northwest Carboniferous basin of Ireland.
Parent Unit: Not Applicable (-)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Type Area  Southwest part of County Tyrone in the area of the Clogher Valley, centred on 10km Grid Square H24 34. 
Type Area  South and west County Fermanagh in area of Fermanagh Highlands, centred on 10km Grid Square H21 34. 
Brandon, A. 1977. The Meenymore Formation: an extensive intertidal evaporitic formation in the Upper Visean (B2) of north-west Ireland. Report of the Institute of Geological Sciences, No.77/23, p.14. 
1:50K maps on which the lithostratigraphical unit is found, and map code used: