The Aggregates of Herefordshire & Worcestershire
The counties of Herefordshire and Worcestershire expose rocks which represent almost 700 million years of Earth History, from the Precambrian gneiss and schists of the Malvern Hills, through the Jurassic limestone of the Cotswolds to the sand and gravels laid down at the end of the Last Ice Age.
As shown on the map above, the geology of the two counties differs greatly. Worcestershire is dominated by Triassic sandstones and mudstones that underlie the Severn Vale. Herefordshire, on the other hand, is dominated by the Devonian Old Red sandstones and the limestone-shale successions of the Silurian period.
Aggregate has been quarried from many of the rock units across both counties, although extraction is concentrated in those units that contain the greatest proportion of hard, coarse grained or crystalline material. The densest distribution of aggregates quarries can thus be found in the igneous rocks of the Malverns; the Silurian limestone and shale sequences of areas such as the Woolhope Dome and west Worcestershire hills; conglomerate layers in the Old and New Red Sandstones; Jurassic limestones of south-east Worcestershire; and the Quaternary sand and gravel deposits along the major rivers.