The Dalradian Supergroup in Scotland, Shetland and Ireland

Abstract

The Dalradian Supergroup, comprising the Grampian (oldest), Appin, Argyll and Southern Highland (youngest) groups (Fig. 13) consists of lithologically diverse metasediments and typically mafic metavolcanic rocks. The supergroup is probably entirely late Precambrian in age and underlies an area of about 48000 km² in north and west Ireland, Scotland and Shetland. Neither the base nor the top of the Dalradian is seen but, taking the maximum thickness preserved for every group and making no allowance for tectonic thickening, it is calculated to have a total cumulative thickness of c. 25.5 km. This second and completely revised edition of Special Report No. 6 provides a comprehensive review and report of work earned out since 1975. It emphasizes the relationship between, and the correlation of, the units in to which the Precambrian rocks of England, Ireland, Scotland, Wales and the Channel Islands have been divided The chapters also provide a comprehensive bibliography of the work on which the correlations have been based.