The BGS Lexicon of Named Rock Units — Result Details

Trentishoe Member

Computer Code: TGR Preferred Map Code: notEntered
Status Code: Pending Upgrade
Age range: Eifelian Age (DI) — Eifelian Age (DI)
Lithological Description: Thick sequence mainly of grey, purple and green quartzitic fine- to medium-grained sandstone, commonly parallel laminated and convolute-bedded, with shale and silty shale interbeds. Abundant scoured surfaces and silty drapes. Scattered scarce remains of Psilophyton sp. and a calamitid-like stem. Local distictive facies of deformed laminae of red siltstones and very fine-grained sandstones in which desiccation cracks alternate with convolute laminae.
Definition of Lower Boundary: ?Conformable on rocks of the Hollowbrook Member (q.v.).
Definition of Upper Boundary: Overlain ?conformably by rocks of the Rawns Member (q.v.)
Thickness: c.1250m (Tunbridge, 1978).
Geographical Limits: North Devon - west Somerset.
Parent Unit: Hangman Sandstone Formation (HASA)
Previous Name(s): Trentishoe Grits (-960)
Alternative Name(s): none recorded or not applicable
Type Section  Cliff sections between Combe Martin Bay and Woody Bay, and between Lynmouth Bay and Minehead. 
Tunbridge, I P. 1978. North Devon - Lower and Middle Devonian: Hangman Sandstone Group. 9-13 in Scrutton, C T (Editor), A field guide to selected areas of the Devonian of south-west England. International Symposium on the Devonian System. (PADS 78). (Palaeontological Association). 
Lane, R. 1965. The Hangman Grits - an introduction and stratigraphy. Proceedings of the Ussher Society, Vol.1, 166-167. 
Evans, J W. 1922. The geological structure of the country round Combe Martin. Proceedings of the Geologists' Association, Vol.33, 201-228. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable