The BGS Lexicon of Named Rock Units — Result Details

Arnbath Psammite Formation

Computer Code: ARPS Preferred Map Code: ArPs
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Medium- to thickly-bedded psammite and semipelite; coastal section contains a basal quartzite member; elsewhere locally contains units of 'boulder bed', a metadiamicton with sparse cobble clasts of granitic and metasedimentary rocks.
Definition of Lower Boundary: Base faulted out in coast section; elsewhere rapid transition is inferred from graphitic semipelites and limestones of Fordyce Limestone Formation.
Definition of Upper Boundary: Change from interbedded psammite and semipelite to thick-bedded quartzite.
Thickness: Increases from c.75m at Newton [542 619] to c.200m at coast, where it is partly repeated by a ductile thrust of the Keith Shear Zone.
Geographical Limits: Coast section from Red Haven to 150m southeast of Foul Hole [NJ 563 663-579 666]; extends southwards as far as Newpark [NJ 530 606].
Parent Unit: Islay Subgroup (DBIS)
Previous Name(s): Durn Hill Quartzite (-26)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Coastal section from to Red Haven to 150m south-east of Foul Hole. 
Reference(s):
Spencer, A M and Pitcher, W S, 1968. Occurrence of the Portaskaig Tillite in north-east Scotland. Proceedings of the Geological Society of London, No.1650, 195-198. 
Stephenson, D and Gould, D , 1995. British Regional Geology: the Grampian Highlands (4th edition). (London: HMSO for the British Geological Survey), 67-68. 
Stephenson, D, et al. 1993. Stratigraphy and correlation of the Dalradian rocks of the East Grampian Project area. British Geological Survey Technical Report WA/93/91. 
Harris, A L, Haselock, P J, Kennedy, M J and Mendum, J R, 1994. The Dalradian Supergroup in Scotland, Shetland and Ireland. 33-53 in Gibbons, W E and Harris, A L (editors). A revised correlation of Precambrian rocks in the British Isles. Special Report of the Geological Society, London, No.22. 
Read, H H, 1923. Geology of the country around Banff, Huntly and Turriff, Lower Banffshire and north-west Aberdeenshire. Memoir of the Geological Survey, Scotland Sheets 86 and 96 (Scotland). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S096