parts of this sequence occur in the Neen Sollars and Caynham areas of the south of the county. Northwest of the Church Stretton Fault Zone, the Pentamerus and Purple Shales wrap around the southern and western margins of the block of Precambrian rocks of the Long Mynd and the district extending west to the Vale of Montgomery. They are overlain by the sandstones, siltstones and mudstones variously of the Sheinwoodian age Bromsleymill Shale Formation and then by the Aston Mudstone, Oakeley Mynd and Bailey Hill formations of Homerian through Gorstian to Ludfordian age. The succeeding Knucklas Castle, Cefn Einion and Clun Forest formations form the core of the Clun Forest range on the county's western border with Wales. These sequences are further overlain by the Temeside Mudstone and the overlying Raglan Mudstone around Vennington between Westbury and Long Mountain. Devonian Stratigraphically above the Bishop's Frome Limestone is the thick sequence of mudstones, with occasional sandstones, known as the St Maughans Formation, the lowermost part of the Devonian succession in Shropshire, assigned to the Early Devonian epoch. The outcrop occupies much of the country between Ludlow and Bridgnorth and extending to the county boundary south of Cleobury Mortimer. The Emsian age Clee Sandstone Formation overlies the St Maughans rocks around Cleobury Mortimer. In a tract of country to the south of Stottesdon, the Clee Sandstone is overlain by the yellow and sometimes pebbly Farlow Sandstone Formation. Together with the Pridoli strata, these Devonian rocks constitute the Old Red Sandstone of Shropshire. Carboniferous The earliest Carboniferous rocks, the Village Farm and Jackie Parr Limestone formations, are seen in the Lilleshall inlier where they unconformably overlie the Old Red Sandstone sequence. These are in turn overlain unconformably by the Lydebrook Sandstone and Sylvan Limestone formations. Within the latter is the Little Wenlock Basalt. Parts of several small coalfields are found within Shropshire - the Coalbrookdale, Clee Hills, Wyre Forest, Leebotwood and Shrewsbury coalfields, together with the southernmost extension of the Denbighshire Coalfield around Oswestry. At Clee Hill, the Oreton Limestone is succeeded by the Cornbrook Sandstone above which is a sandstone at the base of the Lower Coal Measures. This is overlain by mudstones within which are several coal seams. The sequence is intruded by a sill of dolerite (known locally as 'dhustone'). At Brown Clee, Pennine Coal Measures lying directly on the late Devonian Clee Sandstone, form the upper parts of Abdon