A revised age and correlation for the topmost Sholeshook Limestone Formation (Ashgill) of South Wales

Abstract

SummaryThe age of the youngest part of the Sholeshook Limestone Formation is reconsidered in the light of recent advances in knowledge of Ashgill trilobite faunas. A low Rawtheyan (Zone 5) age is suggested and correlations are proposed with Ashgill rocks in the SW Berwyns and with part of the Swindale Limestone Formation of Cross Fell. The Cautleyan/Rawtheyan boundary is a level at which faunal changes are sufficiently pronounced to permit reliable and precise correlation.