The Silurian rocks of the Tortworth Inlier,Gloucestershire

The Silurian succession in the Tortworth Inlier includes strata belonging to the three main divisions of the System. The Upper Llandovery, which rests unconformably on Tremadoc beds, consists of about 700 ft. (213 m.) of fine-grained sandstones, mudstones and shales with two igneous bands. The Wenlock Series is represented by some 800 ft. (244 m.) of mudstones, siltstones and calcareous sandstones with impersistent limestone bands at various horizons. The Ludlow succession is incomplete, but at least 300 ft. (91 m.) of mudstones, siltstones and fine-grained sandstones are present, and they pass up conformably into the Downtonian.