The Permian Conglomerates of the Lower Severn Basin

Abstract

I. I ntroduction . B etween the River Severn and the village of Enville in South-east Shropshire, and again round the southern half of the South Staffordshire Coalfield, there are certain bands of rocks cemented and hardened by calcareous matter—namely, calcareous conglomerates, cornstones, and calcareous sandstones—which constitute parts of the group classified by the officers of the Geological Survey as Middle Permian. The object of this paper is to trace the materials composing these calcareous rocks to their sources. The typical Permian sequence of the Shropshire type is, according to Prof. Hull, as follows, in descending order:— Murchison stated that at Coton and Bowhills the calcareous horizons of the Middle Permian consist of ‘( a ) coarse conglomerate, composed chiefly of fragments of Carboniferous Limestone, generally rounded ; . . . . some of them are of an oolitic structure . . . . ( b ) conglomerate, with fewer fragments of limestone, but pebbles of quartz, Old Red Sandstone, ere . . . . . and minute fragments of jasper.’ He pointed out that ‘the nearest known masses of similar [Carboniferous\ rock are in the Carboniferous Limestone of the Clee Hills.’ Ramsay collected from conglomerates, included by him in the Middle Permian, at Gatacre Hall and Four Ashes, near Enville, pebbles of He states that ‘the Carboniferous Limestone pebbles by far predominate,’ and that ‘the nearest Carboniferous Limestone is that of the Titterstone Clee :Hills . . . . The Coalbrookdale limestone contains chert . . . . and in the same district occur igneous and