The BGS Lexicon of Named Rock Units — Result Details

Gravel Caverns Conglomerate Member

Computer Code: GCC Preferred Map Code: GCC
Status Code: Pending Upgrade
Age range: Frasnian Age (DR) — Frasnian Age (DR)
Lithological Description: Greenish grey mudstone with thin black calcareous beds and beds of poorly sorted, matrix-supported conglomerate up to 1.6m thick.
Definition of Lower Boundary: The relationship of the conglomerate to the enclosing mudrock is complex. Sheets and small channels occur commonly and there is considerable invasion of the enclosing mudrock by pebbles at both upper and lower contacts.
Definition of Upper Boundary: The relationship of the conglomerate to the enclosing mudrock is complex. Sheets and small channels occur commonly and there is considerable invasion of the enclosing mudrock by pebbles at both upper and lower contacts.
Thickness: 90m (Gauss, G A and House, M R, 1972).
Geographical Limits: Polzeath area.
Parent Unit: Harbour Cove Slate Formation (HCSL)
Previous Name(s): Great Caverns Conglomerate [Sic] (-4668)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Cliffs between Pentire Haven and Gravel Caverns. Gauss, G A and House, M R, 1972. 
Reference(s):
Gauss, G A and House, M R, 1972. The Devonian successions in the Padstow area, north Cornwall. Journal of the Geological Society of London, Vol.128, 151-172. 
Reid, C, Barrow, G and Dewey, H. 1910. The geology of the country around Padstow and Camelford. Memoir of the British Geological Survey, England and Wales. 
Beese, A P, 1984. Stratigraphy of the Upper Devonian argillite succession in north Cornwall. Geological Magazine, Vol.121, 61-69. 
Selwood, E B, Thomas, J M, Williams, B J, Clayton, R, Durning, B, Smith, O and Warr, L N, 1998. Geology of the country around Trevose Head and Camelford. Memoir of the British Geological Survey, sheets 335 and 336 (England and Wales). 
Fox, H, 1903. Some coast sections in the parish of St Minver. Transactions of the Royal Geological Society of Cornwall, Vol.12, 649-682. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable