The BGS Lexicon of Named Rock Units — Result Details

Exeter Group

Computer Code: EXE Preferred Map Code: EXG
Status Code: Full
Age range: Cisuralian Epoch (PLC) — Cisuralian Epoch (PLC)
Lithological Description: Component formations are predominantly breccia, with subordinate sandstone. All formations are alluvial fan deposits.
Definition of Lower Boundary: Basal formations in Crediton Trough (Cadbury Breccia, Upton Formation, Bow Breccia, Knowle Sandstone) rest unconformably on Bude or Crackington formations. Around and south-west of Exeter, basal formations (Dawlish Sandstone, Whipton Formation, Knowle Sandstone) rest unconformably on Crackington Formation. See definitions of component formations.
Definition of Upper Boundary: Unconformably overlain by Aylesbeare Mudstone Group.
Thickness: At least 700m.
Geographical Limits: From Torbay in the south, north through Newton Abbot to Exeter; all New Red Sandstone strata in the Crediton Trough and probably the Tiverton Trough.
Parent Unit: New Red Sandstone Supergroup (NRS)
Previous Name(s): Lower New Red (-4643)
Lower Sandstone And Breccia (-897)
Marginal Deposits (-2794)
Alternative Name(s): none recorded or not applicable
Type Area  Group named from the city of Exeter, Devon. 
Ussher, W A E, 1902. The Geology of the country around Exeter. Memoir of the Geological Survey of Great Britain, Sheet 325. (England and Wales). 
Henson, M R, 1972. The form of the Permo-Triassic Basin in south-east Devon. Proceedings of the Ussher Society, Vol.3, p.447-457. 
Ussher, W A E, 1906. Chapter on Geology. "In" Victoria History of the Counties of England (Devonshire), p.1-48. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E350 E310 E311 E308 E355 E356 E307