Striae at St. Mullinʹs Cave, County Kilkenny, southern Ireland: their origin and chronological significance

At St. Mullinʹs Cave, County Kilkenny, Ireland, erosional marks on an exposure of Devonian Old Red Sandstone conglomerate record north to south ice flow. The site occurs within the so-called area of `older driftʹ south of the southern Ireland end-moraine (S.I.E.M.). Projecting quartzite cobbles are planated by glacial erosion forming an accordant upper surface. Well preserved striae (alignment 350/355 to 170/175°) are present on each planated clast (n=15). An irregular surface (cm deep) is developed on the finer matrix between clasts and records post-striation mechanical weathering. The striae form a co-linear texture with striae recorded from other sites in Counties Kilkenny and Waterford, and document ice flow southward onto the continental shelf. Although the age of the striae is problematical their relationships to other known glacigenic events in southern Ireland suggest formation by ice flow early in the last glacial cycle.