Proceedings of the Geologists' Association, Volumes 89-90

abundant acritarchs ammonites Apley Barn assemblages associated B.Sc basal basin bioturbated bivalves borehole Bristol Channel Buckman calcareous Callovian Cape Fold Belt Carboniferous chamosite chamosite oolite chert clay Coal contain cores deformation deposits Devonian Dorset east Emsian England environment erosion facies fault fauna Field Meeting foraminifera Formation fossils fragments Geology glauconite gravels Greensand grey Group Hackness Rock Hill horizon Hythe Beds igneous indicate inlier Jl geol Jurassic Kellaways Rock kyanite laminated Limestone lithologies Llandovery loess Lond London Lower marine Marl material medium grained megaripples Mesozoic Middle mudstones occur Old Red Sandstone Oolite Ordovician outcrop Palaeozoic pebbles Ph.D plant Plate present Proc quarry quartz Red Crag samples sand sandy sedimentary sediments sequence shales shear shell silt siltstones silty Silurian southern Sowerby species spicules sponge spicules spores stratigraphic structures suggests tectonic thick thin upper volcanic Wales Wenlock Yorkshire zone