The BGS Lexicon of Named Rock Units — Result Details

Three Wells Sandstone Member

Computer Code: TWSA Preferred Map Code: TWSA
Status Code: Full
Age range: Lochkovian Age (DO) — Pragian Age (DP)
Lithological Description: Sandstone, pebbly sandstone and conglomerate with thin andesitic lavas.
Definition of Lower Boundary: Passes conformably and diachronously downwards and laterally to the south into the conglomerate of the undivided Catterline Conglomerate Formation, taken at point where sandstone becomes predominant in the upward sequence.
Definition of Upper Boundary: Passes conformably and diachronously upward into conglomerate, taken where conglomerate becomes predominant in the undivided Catterline Conglomerate Formation.
Thickness: From 46m to 85 m thick, increasing south-eastwards to 360m
Geographical Limits: Between Castle of Allardice (NO 818 741), and the foreshore at Narrows Cottage, by Johnshaven.
Parent Unit: Catterline Conglomerate Formation (CATC)
Previous Name(s): Johnshaven Formation [Obsolete Name And Code: See CATC] (JNF)
Three Wells Sandstone Formation (-3738)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  Along the foreshore from Johnshaven to Narrows Cottage. 
Partial Type Section  Three Wells Quarry, near Inverbervie. 
Reference(s):
Armstrong, M and Paterson, I B, 1970. The Lower Old Red Sandstone of the Strathmore Region. Report of the Institute of Geological Sciences No.70/12 
Carroll, S, 1994. Geology of the Inverbervie and Catterline district, 1:10 000 sheets NO87NW, NO87NE and NO87SW. British Geological Survey, Technical Report, WA/94/20. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S067 S057