The BGS Lexicon of Named Rock Units — Result Details

Roxby Formation

Computer Code: ROX Preferred Map Code: RoF
Status Code: Full
Age range: Guadalupian Epoch (PUG) — Early Triassic Epoch (TE)
Lithological Description: Mudstone and siltstone, reddish brown, with subordinate sandstone. Sulphates (gypsum, anhydrite) common towards base.
Definition of Lower Boundary: Diachronous; taken at top of highest anhydrite (Littlebeck Anhydrite) in subsurface, and at top of Brotherton Formation at outcrop.
Definition of Upper Boundary: Conformable; taken at gradational and diachronous transition into sandstones of Sherwood Sandstone Group.
Thickness: 0-130m (129m in Staithes S20 borehole - Smith et al, 1986).
Geographical Limits: Eastern England; dies out in south Nottinghamshire.
Parent Unit: Zechstein Group (ZG)
Previous Name(s): Permian Upper Marls (B) [Obsolete Name And Code: Use ROX] (PUM)
Upper Marl (-2401)
Saliferous Marl (-4304)
Permian Upper Marls (A) [Obsolete Name And Code: Use ROX] (UPM)
Permian Upper Marl (-503)
Upper Permian Marl (-504)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Staithes S20 borehole [NZ71ne/14], Boulby, Cleveland: depth range 920.5-1049.8m. Curated core held at BGS Keyworth. 
Reference(s):
Smith, D B, Harwood, G M, Pattison, J and Pettigrew, T H. 1986. A revised nomenclature for Upper Permian strata in eastern England. 9-17 in Harwood, G M and Smith, D B (editors). The English Zechstein and Related Topics. Geological Society Special Publication No.22. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E062 E033 E070 E052 E078 E090 E082 E043 E042 E126 E087 E032 E027 E127 E142