Page:VCH Worcestershire 1.djvu/41

 GEOLOGY It is only in certain localities and at certain horizons that fossils have been obtained in abundance. The Lower Old Red Sandstone comprises red marls and sandstones, and beds of impure concretionary and unfossiHferous limestone, known as cornstones ; and it has yielded remains of Pteraspis and Cephalaspis among fishes ; also Pterygotus and Stylonurus among Crustacea. The rocks are exposed along the western side of the Malvern range, and along the borders of the Teme at Tenbury. At Cradley, west of Malvern, the sandstones have been quarried for building-stone. The soil is variable, but much of it is a fertile loam suitable for hop-gardens and orchards. East of Tenbury there are masses of tufa or travertin derived from the cornstones of the Old Red Sandstone, and which have been accumulated in narrow dells at the Southstone Rock and near Spouthouse Farm.^ The Lower Old Red Sandstone, as previously remarked, is quite conformable with the Silurian. The earth-movements affected both formations ; but Prof Groom is of opinion that the Malvern range arose later on between the Middle and Upper Coal Measures.^ Near Bewdley, in the Trimpley anticline which may be regarded as a nor- therly prolongation of the Malvern-Abberley range, the Old Red Sand- stone has been folded and probably to some extent thrust over the Coal Measures. According to Mr. T, C. Cantrill the movement advanced from the south-east, and was effected apparently during the period of the Upper Coal Measures.^ The Upper Old Red Sandstone, which contains beds of quartzose conglomerate as well as sandstone, is not exposed in our district. COAL MEASURES Portions of the Forest of Wyre coalfield are included in Worces- tershire, and they comprise a wooded tract extending westwards from Bewdley and southwards towards the Abberley Hills. The formation is made up of a series of sandstones, grits and shales, with bands of Spirorbis-infiionQ and a few seams of coal and ironstone. The beds rest irregularly on the Old Red Sandstone, and attain a thick- ness of from 200 to about 1,700 feet. The strata are much disturbed, and they are locally altered by the intrusion of a sill or dyke of fine- grained basalt, an igneous rock which forms a ridge at Shatterford, and occurs for some distance in the country east of Upper Arley. The coal-seams are thin, sulphurous, and of poor quality in the Worcestershire region, where the beds belong mainly to the Upper Coal Measures, but they have been worked at Pensax, Abberley, Mamble, Arley Wood and Shatterford. A boring near Dowles Brook was carried ' Quart. 'Journ, Geol. Soc, vols. Iv. p. 157, Ivi. p. 165. ' ' A Contribution to the Geology of the Wyre Forest Coalfield,' 8vo, Kidderminster, 1895, pp. 13, 16, 36. II
 * Murchison, Proc. Geol. Soc, vol. ii. p. 78.