The BGS Lexicon of Named Rock Units — Result Details

Ardwell Bridge Basic Volcanic Member

Computer Code: ABBV Preferred Map Code: notEntered
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Amphibolite/metabasalt, mostly aphyric, locally with pillow structures. Interbanded with greywacke grits and slaty to phyllitic pelites.
Definition of Lower Boundary: Top of highest persistent sheet of fine-grained ultramafic rock in the Blackwater Formation.
Definition of Upper Boundary: Top of highest persistent metabasalt sheet. Background lithology changes from greywacke grits with pelites to persistent pelites of the Corinacy Pelite Member.
Thickness: c. 550-650 m (based on outcrop width with no allowance for probable folding).
Geographical Limits: 500 to 750 m-wide outcrop extending from Dead Wife's Hillock [NJ 340 267] to Ardwell Bridge and along valley of River Deveron to Gaul Burn, Succoth [NJ 430 357], Cabrach area, Moray District. 1:50 000 sheets 75E and 85E.
Parent Unit: Blackwater Formation (BLWR)
Previous Name(s): Part Of The Ardwell Bridge Lavas (Informal Name) (-1940)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Black Water from King's Haugh to 250 m below Blackwater Bridge (commonly known as Ardwell Bridge). 
Reference(s):
Fettes, D J, Lesley, A G, Stephenson, D and Kimbell, S F, 1991. Disruption of Dalradian stratigarphy along the Portsey Lineament from new geological and magnetic surveys. Scottish Journal of Geology, Vol.27, 57-73. 
MacGregor, S M A and Roberts, J L, 1963. Dalradian pillow lavas, Ardwell Bridge, Banffshire, Geological Magazine, Vol. 100, 17-23. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S075