The BGS Lexicon of Named Rock Units — Result Details

Glengawna Formation

Computer Code: GAA Preferred Map Code: GA
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Interbedded psammite, semi-pelite and graphitic pelite.
Definition of Lower Boundary: Gradational boundary with underlying Glenelly Formation.
Definition of Upper Boundary: Gradational boundary with overlying Mullaghcarn Formation.
Thickness: c.1km
Geographical Limits: 0.5-1.5km wide belt in north County Tyrone, Killyclogher-Gortin Glen to Glenlark.
Parent Unit: Southern Highland Group (SOHI)
Previous Name(s): Glengawna Formation [Obsolete Code: Use GAA] (DCGF)
Glengawna Formation (Obsolete Code: Use GAA) (-1549)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  Lower boundary stratotype. Bottom of last major graphitic schist band in Altavaran Glen, Gortin. 
Partial Type Section  Upper boundary stratotype. Southbank tributary of Glenlark Burn onset of pale grey albitic flags, psammite and schist of Mullaghcarn Formation. 
Reference(s):
Arthurs, J W, 1976. The geology and metalliferous mineral potential of the Sperrin Mountains area. Geological Survey of Northern Ireland, Special Report No.1, 119pp, 2app, 2 figs, 7 tables, 102 maps. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
N26