The BGS Lexicon of Named Rock Units — Result Details

Hawthorn Limestone Member [Obsolete: use HUR]

Computer Code: HAWL Preferred Map Code: HAWL
Status Code: Index Level
Age range: Brigantian Substage (CX) — Brigantian Substage (CX)
Lithological Description: [Obsolete: use HUR] Upper part is a creamy weathering nodular limestone in kaolinitic matrix, grey or brownish-grey muddy fine-grained limestone below.
Definition of Lower Boundary: Base of limestone or base of calcareous shales where present, overlying non-calcareous shales with a thin coal seam.
Definition of Upper Boundary: Upper surface of nodular limestone overlain by mudstone.
Thickness: 12m maximum, 3 - 5m commonly
Geographical Limits: Muirkirk, Gass Water and Glenmuir areas of Ayrshire (Strathclyde).
Parent Unit: none recorded or not applicable
Previous Name(s): Muirkirk Main Limestone [Obsolete Name and Code: Use HAWL] (-2232)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Ashaw burn, 370m upstream from old railway bridge, and disused quarry 310m southsouthwest of old railway bridge. 
Reference(s):
none recorded or not applicable
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S015 S023 S014