The BGS Lexicon of Named Rock Units — Result Details

St Erth Formation

Computer Code: SE Preferred Map Code: notEntered
Status Code: Full
Age range: Pliocene Epoch (NP) — Pliocene Epoch (NP)
Lithological Description: Fossiliferous clay and sandy clay on ferruginous and quartzose sands. The clays have yielded abundant marine mollusca and foraminifera.
Definition of Lower Boundary: Base of sands not seen but presumed to be Mylor Slate Formation (Late Devonian). Sections recorded by H Dewey (unpublished IGS records) in the north part of Vicarage Pit indicate shelly clay resting unconformably on bedrock.
Definition of Upper Boundary: Overlain by and in irregular contact with Head.
Thickness: Deposit greater than 4m comprising c.4m of highly fossiliferous shelly clay on pebbly fine sand.
Geographical Limits: Isolated outlier, 0.3 x 1.4km, 1km east of the village of St Erth, Cornwall.
Parent Unit: British Coastal Deposits Group (COAS)
Previous Name(s): St Erth Beds (*824)
Alternative Name(s): St Erth Beds
Stratotypes:
Type Section  Vicarage Pit, St Erth, Cornwall. Type section based on north section of pit trenched in 1966 and reported by Mitchell et al. (1973). 
Reference(s):
Mitchell, G F, Catt, J A, Weir, A H, McMillan, N F, Margerel,J P, and Whatley, R C. 1973. The Late Pliocene marine formation of St Erth, Cornwall. Philosophical Transactions of the Royal Society, London,Vol.226, Series B, 1-37. 
Millett, F W. 1895. The foraminifera of the Pliocene beds of St Erth. Transactions of the Royal Geological Society of Cornwall, Vol.11, 655-661. 
Millett, F W. 1897. The foraminifera of the Pliocene beds of St Erth in relation to those of other deposits. Transactions of the Royal Geological Society of Cornwall, Vol.12, 43-46. 
Messenger, R W, Hart, M B, Pirrie, D, Allen, L, Taylor, G K and Dashwood, B. 2005. The St Erth Formation: Geometry of the deposit and micropalaeontology. Geoscience in south-west England, Vol.11, 93-98. 
Reid, C. 1890. The Pliocene deposits of Britain. Memoir of the Geological Survey. 
Jenkins, D G, Whittaker, J E and Carlton, R. 1986. On the age and correlation of the St Erth Beds, S W England based on planktonic foraminifera. Journal of Micropalaeontology, Vol.5, 93-105. 
Mitchell, G F. 1966. The St Erth Beds - an alternative explanation. Proceedings of the Geologists' Association, Vol.76, 345-366. 
Roe, I, Hart, M B, Taylor, G K and Marks, A. 1999. The St Erth Formation: history of the clay workings, geological setting and stratigraphy. Proceedings of the Ussher Society, Vol.9 304-309. 
Jenkins, D G. 1982. The age and palaeoecology of the St Erth Beds, southern England based on planktonic foraminifera. Geological Magazine, Vol.119, 201-205. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E351