The BGS Lexicon of Named Rock Units — Result Details

Foxmould Member

Computer Code: FXMD Preferred Map Code: Fx
Status Code: Pending Upgrade
Age range: Albian Age (KA) — Albian Age (KA)
Lithological Description: Sandstone, glauconitic, calcareous in part, greenish grey weathering to foxy brown (reddish-brown) sand; concretionary "doggers" and tabular sandy limestones at several levels.
Definition of Lower Boundary: In west Dorset's coastal sections the base is a conformable and gradational transition from the sandy mudstones of the Gault Formation to the sandstones of the Foxmould Member. Elsewhere the boundary is placed at an unconformity where the Foxmould Member rests on strata ranging from Triassic (in the west) to Lower Jurassic (in the east).
Definition of Upper Boundary: The upper boundary is at the base of a mineralized hardground surface (Culverhole Hardground) above which concretionary calcareous sandstones are absent and cherts are common in the Whitecliff Chert Member of the Upper Greensand Formation.
Thickness: 30 to 32m.
Geographical Limits: Devon and west Dorset. Mapped on Sheets 326 (Sidmouth) and 327 (Bridport); continuation on Sheet 311 (Wellington). Known to be present in the subcrop at least as far north as the Winterborne Kingston Borehole SY89NW/1 [SY8470 9790] (300 to 324m depth) (Rhys et al., 1982).
Parent Unit: Upper Greensand Formation (UGS)
Previous Name(s): Foxmould And Cowstone Beds (-268)
Alternative Name(s): Foxmould
Foxmould Sands
Type Section  Whitecliff and adjacent cliff sections at Seaton Hole, 2km west of Seaton esplanade, Devon. Jukes-Browne, A J and Hill, W (1900, 195-197 and Plate). 
Rhys, G H, Lott, G K, and Calver, M A. 1982. The Winterborne Kingston borehole, Dorset, England. Report of the Institute of Geological Sciences, No.81/3. 
Woodward, H B and Ussher, W A E, 1911. Sidmouth and Lyme Regis. Memoir of the Geological Survey, Sheets 326 and 340 (England and Wales). 
Jukes-Browne, A J and Hill, W. 1900. The Cretaceous Rocks of Britain. 1. Gault and Upper Greensand. Memoir of the Geological Survey of Great Britain. 
De La Beche, H. 1826. Transactions of the Geological Society, Series 2, Vol.II, p.113. 
Edwards, R A, Gallois, R W and Hamblin, R J O. 2004. Geology of the Sidmouth district. Sheet Explanation of the British Geological Survey, Sheets 326 and 340 (England and Wales). 
1:50K maps on which the lithostratigraphical unit is found, and map code used: