Geology of the Swansea district : a brief explanation of the geological map Sheet 247 Swansea

This Sheet Explanation provides a summary of the geology of the district covered by the geological 1:50 000 Series Sheet 247 Swansea, published as revised Bedrock Geology and Superficial Deposits editions in 2011. A more detailed account of the geology is provided by the Sheet Description (Barclay, in press). The Swansea district extends from Gower and Llanelli in the west to Port Talbot and Neath in the east, the city of Swansea occupying much of the central part. Carboniferous rocks underlie the entire district, except for some Late Devonian conglomerates in the core of the Cefn Bryn Anticline in Gower. Late Carboniferous (Pennsylvanian) rocks of the Pennant sandstone-dominated Warwickshire Group are the most widespread. Steeply dipping, folded and faulted measures of the South Wales Coal Measures Group and Namurian Marros Group occupy the lower coastal area, except for the Mississippian limestones of the Pembroke Limestone and Avon groups of the Gower.