The BGS Lexicon of Named Rock Units — Result Details

Penwhapple South Group [Obsolete Name: Use NEWL]

Computer Code: PSO Preferred Map Code: PSo
Status Code: Index Level
Age range: Rhuddanian Age (SR) — Aeronian Age (SA)
Lithological Description: Mudstone and sandstone: see constituent formations (Tralorg, Saugh Hill Grits, Pencleuch Shale).
Definition of Lower Boundary: Disconformable junction with Shalloch Formation (Ordovician).
Definition of Upper Boundary: Disconformable junction with Lower Camregan Grits Formation (Penwhapple North Group).
Thickness: c.240-700m
Geographical Limits: Girvan area, south-west Scotland.
Parent Unit: Not Entered (?)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  See constituent formations. 
Reference(s):
Floyd, J D and Williams, M. 2003. A revised correlation of Silurian rocks in the Girvan district, SW Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences, Vol. 93 (for 2002), 383-92. 
Cocks, L R M and Toghill, P, 1973. The biostratigraphy of the Silurian rocks of the Girvan District, Scotland. Journal of the Geological Society of London, Vol. 129, 209-243. 
Cameron, I B, Stone, P and Smellie, J, 1986. Geology of the Country around Girvan. Explanation of 1:50 000 sheet. British Geological Survey, Sheet 7, Scotland. 
Lapworth, C, 1882. The Girvan Succession. Quarterly Journal of the Geological Society of London, Vol. 38, 537-666. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S007