The geology of Staffordshire in the West Midlands region of England is largely characterised by sedimentary bedrock of late Palaeozoic to early Mesozoic age overlain by a suite of superficial materials deposited during the Quaternary period.
They form part of a grouping known as the Midlands Minor Intrusive Suite, other surface occurrences of which are at the Wrekin and near Nuneaton.
A tiny outcrop of the underlying Monks Park Shale on the county boundary at Dost Hill is Staffordshire's oldest rock, dating back to the Merioneth (British regional) epoch between 499 and 485 million years ago.
The Carboniferous period (359 - 299 million years ago) is represented by limestones, mudstones and sandstones in the northern third of Staffordshire with further outcrops along its margins elsewhere.
The southwestern part of the White Peak lies within Staffordshire, its name owing to the presence of grey-white Carboniferous Limestone in the landscape.
Three formations are mapped in the area (uppermost/youngest first): The Millstone Grit Group outcrops across Staffordshire Moorlands district in the north of the county.
It forms prominent north to north-easterly dipping scarps at Back Forest and nearby Hangingstone and provides the bedrock in which the chasm of Lud's Church has opened up.
The South Staffordshire Coalfield is now largely within the county of West Midlands and forms the basis of the Black Country.
A small area of Lower Coal Measures rocks extends beneath Goldsitch Moss in the northern angle of the county.
Warwickshire Group strata overlie the Coal Measures in the north and are found again (as the Salop Formation) around Loggerheads and Adbaston.
In the southwest, the ice did not advance beyond a line drawn south of Wolverhampton and Bridgnorth thus no Devensian till is known from the southernmost part of the county whereas it is plentiful elsewhere.
[7] During the Devensian, 'Irish Sea ice' moving across the Cheshire Plain reached to the western slopes of the Roaches, Hen Cloud and Morridge.
The overlying Warwickshire Group rocks have yielded not only building stone but also clays for brick-making and in the case of the Etruria Formation, for pottery.