Published online by Cambridge University Press: 01 May 2009
THE Millstone Grit described in this paper forms a belt of country about a mile wide, stretching from west-north-west to east-south-east across the north of the Gower Peninsula. Reference is also made to small areas of Millstone Grit preserved in synclines at Oxwich and Porteynon on the south coast of Gower. These areas form the most important outcrops of this formation on the south of the South Wales Coalfield. Further east the Millstone Grit is thinner and it is not exposed for some miles to the east of Swansea Bay, as it is concealed by Mesozoic rocks.