The BGS Lexicon of Named Rock Units — Result Details

Sella Park Tuff Member

Computer Code: SEP Preferred Map Code: notEntered
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Spherulitic and silicified welded rhyolitic tuff.
Definition of Lower Boundary: Taken at the sharp change from bedded tuff, lapilli-tuff and sandstone of the Newton Manor Sandstone Formation.
Definition of Upper Boundary: Overlain by other members of the Yottenfews Tuff Formation: immediately by laminated fine-grained sandstone.
Thickness: 91m (uncorrected for structural dip or borehole deviation from vertical).
Geographical Limits: Sellafield borehole 7A (NY00SE/36) only.
Parent Unit: Yottenfews Tuff Formation (YOT)
Previous Name(s): Sella Park Member (-3667)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Sellafield borehole No.7A, BGS Registered No. NY00SE/36, 680.96-771.5m below Rotary Table Elevation, 627.90m-718.44m below OD. 
Reference(s):
Millward D, Beddoe-Stephens, B, Williamson, I T, Young, S R and Petterson, M G, 1994. Lithostratigraphy of a concealed caldera-related ignimbrite sequence within the Borrowdale Volcanic Group of west Cumbria. Proceedings of the Yorkshire Geological Society, Vol.50, part 1, 25-36. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable