 The tillite is overlain by the Bonahaven Dolomite and then the Jura Quartzite which can reach up to 5km thick but which is more typically between 500 and 1000m thick.Psammites and pelites occur within the sequence in the Ladder Hills area.The Easdale Subgroup consists of a basal Scarba Conglomerate overlain by the Craignish Phyllite.