VI.—The Carboniferous Succession in the Forest of Dean Coalfield

Abstract

The following preliminary account is presented as the result of several weeks of field-work on the northern and eastern margins of the Forest of Dean Coalfield, carried out partly in 1910 and partly in the present year. The area which I have examined lies almost wholly within Sheet 43 S.E. of the 1 inch Geological Survey Map (Old Series), but extends a short distance into Sheet 43 S.W. In portions of this area, the Lower Carboniferous rocks have been studied in detail and mapped. The Coal Measures, however, have as yet been examined only in their relation to the Lower Carboniferous strata. The present communication is, therefore, confined to a demonstration of the important unconformity which exists between the Coal Measures and the Lower Carboniferous rocks, together with a brief description of the latter. I am continuing my investigations, and I hope to give at some future date a more comprehensive account of the geology of the coalfield. In the meantime, the following outline may be of interest.