Uriconian


The Uriconian rocks of Shropshire (Wrekin Terrane) are thought to be potentially related to the Longmyndian Supergroup of the Stretton Hills, Shropshire, United Kingdom. Current geological profiling of the terranes suggests that the Uriconian rocks are of Precambrian age (Neoproterozoic Phases 2 and 3). The Uriconian Rocks outcrop to the southeast of the Long Mynd area of the Welsh Borderland Fault System and beyond the Church Stretton Fault which trends northeast-southwest across the area. The Stretton Hills are composed primarily of arenaceous (quartz rich sand) beds assigned to the Longmyndian Supergroup. The Longmyndian rocks are a c.6 km thick group of volcaniclastic and bentonitic sediment horizons. The Uriconian have long thought to be older than the Longmyndian and generally outcrop to the southeast of the latter within northeast-southwest trending lineaments suggesting basement influence for the regional structure.