The BGS Lexicon of Named Rock Units — Result Details

Orton Group

Computer Code: OG Preferred Map Code: OG
Status Code: Full
Age range: Chadian Substage (CI) — Holkerian Substage (CQ)
Lithological Description: Limestone, sandstone, mudstone.
Definition of Lower Boundary: Conformable base of lowest limestone unit overlying Carboniferous Basal (Basement) Beds, Ravenstonedale Group or Cockermouth Lavas.
Definition of Upper Boundary: Overlain by Alston Group.
Thickness: Approximately 40m
Geographical Limits: Ravenstonedale area, Cumbria.
Parent Unit: Not Entered (?)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Ravenstonedale area, Cumbria. 
Reference(s):
Burgess, I C, 1970. In annual report for Institute of Geological Sciences for 1969, p.31. 
Arthurton, R S, and Wadge, A J. 1981. Geology of the country around Penrith. Memoir for geological sheet 24. Institute of Geological Sciences, London, HMSO. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E024 E023 E018 E026 E040 E031