The BGS Lexicon of Named Rock Units — Result Details

Troon Volcanic Member

Computer Code: TVL Preferred Map Code: TVL
Status Code: Full
Age range: Namurian Stage (CN) — Namurian Stage (CN)
Lithological Description: Olivine microporphyritic basalt (Dalmeny type).
Definition of Lower Boundary: Taken at the lithological change from sandy clastic strata of the underlying parent Passage Formation to basaltic lava.
Definition of Upper Boundary: Taken at the base of the Ayrshire Bauxitic Clay Member, and defined as the lithological change from olivine basalt to bauxitic clay. The boundary is described as normally gradational.
Thickness: To 165m
Geographical Limits: Presently used within north and central Ayrshire.
Parent Unit: Passage Formation (PGP)
Previous Name(s): Passage Group Lavas (-2504)
Troon Volcanic Formation (-1244)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Gailes Farm Borehole NS33SW/1, from about 32.84m (100.1') to 207.68m (663') depth. 
Type Section  Lugton Water 
Reference(s):
Browne, M A E, Dean, M T, Hall, I H S, McAdam, A D Monro, S K and Chisholm, J I. 1999. A lithostratigraphical framework for the Carboniferous rocks in the Midland Valley of Scotland. British Geological Survey Research Report, RR/99/07. 
Monro, S K. 1999. Geology of the Irvine District. Memoir of the British Geological Survey, Sheet 22W and part of 21E (Scotland). 
Browne, M A E, Dean, M T, Hall, I H S, McAdam, A D and Monro, S K, 1995. A review of the lithostratigraphy of the Carboniferous rocks of the Midland Valley of Scotland. BGS Technical Report, WA/95/25R. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S022 S014 S014 S022