The BGS Lexicon of Named Rock Units — Result Details

Stoke Park Rock Bed

Computer Code: SPRK Preferred Map Code: notEntered
Status Code: Index Level
Age range: Carnian Age (TC) — Carnian Age (TC)
Lithological Description: Mudstone, greenish grey, silty, sandy, dolomitic, well indurated; nodules of celestite (strontium sulphate) common, especially towards top.
Definition of Lower Boundary: Conformable, at abrupt or near abrupt upward change from the reddish brown mudstone of the Mercia Mudstone Group (undivided) to the greenish grey dolomitic sandy mudstone of the Stoke Park Rock Bed.
Definition of Upper Boundary: Conformable, at gradational upward transition from greenish grey mudstone with celestite of the Stoke Park Rock Bed to reddish brown and greenish grey mottled mudstone of the Mercia Mudstone Group.
Thickness: 0.5 to 2m
Geographical Limits: Crops out in northern part of Bristol area and in south Gloucestershire.
Parent Unit: Mercia Mudstone Group (MMG)
Previous Name(s): Severnside Evaporite Bed (-3043)
Alternative Name(s): Butcombe Sandstone Member
Stratotypes:
Type Area  Stoke Park, north of Stapleton, Bristol. Kellaway and Welch (1993). 
Reference(s):
Nickless, E F P, Booth, S J and Mosley, P N. 1975. The celestite deposits of the Bristol area. Transactions of the Institution of Mining and Metallurgy, Vol.B84, 62-64. 
Kellaway, G A and Welch, F B A, 1993. Geology of the Bristol district. Memoir of the British Geological Survey Special Sheet [England and Wales]. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable