The BGS Lexicon of Named Rock Units — Result Details

Treworgans Sandstone Member

Computer Code: TRSA Preferred Map Code: notEntered
Status Code: Pending Upgrade
Age range: Mid Devonian Epoch (DM) — Mid Devonian Epoch (DM)
Lithological Description: Sandstone beds to 6m (grainflows) with interbeds of grey slaty mudstone and yellow-green laminated siltstone.
Definition of Lower Boundary: Conformable within the Grampound Formation.
Definition of Upper Boundary: Conformable within the Grampound Formation.
Thickness: To 40m
Geographical Limits: Present at least along the northern margin of the Mevagissy (353) sheet and in the northeast corner of the Falmouth (352) sheet areas.
Parent Unit: Grampound Formation (GRAD)
Previous Name(s): Grampound Grit [Obsolete Name And Code: Use TRSA Or GRAD] (GPG)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  Treworgans Quarry and its immediate vicinity. 
Partial Type Section  Coastal section at Pentewan. 
Reference(s):
Leveridge, B E, 1987. Geological description for 1:10000 sheets SW84NW, NE, SW, Se and parts of SW94NW and SW (Truro). 51pp. (Keyworth: British Geological Survey.) 
Leveridge, B E, Holder, M T and Goode, A J J, 1990. Geology of the country around Falmouth. Memoir of the British Geological Survey, Sheet 352 (England and Wales). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E352 E353 E354