A feature of the geology of England, the Stafford Basin extends beneath much of the

Midlands The Midlands is the central region of England, to the south of Northern England, to the north of southern England, to the east of Wales, and to the west of the North Sea. The Midlands comprises the ceremonial counties of Derbyshire, Herefor ...

county of

Staffordshire Staffordshire (; postal abbreviation ''Staffs''.) is a Ceremonial counties of England, ceremonial county in the West Midlands (region), West Midlands of England. It borders Cheshire to the north-west, Derbyshire and Leicestershire to the east, ...

. It is a depositional basin which was initiated during the

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the s ...

period and continued to receive

sediment Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of ...

during the

Triassic The Triassic ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is t ...

period and probably thereafter. Part of a more extensive set of linked basins, it connects with the Cheshire Basin to the northwest, the Worcester Basin via the Bratch Graben to the south and the Needwood Basin to the east. It is flanked in part to the west by the Coalbrookdale Coalfield and to the east by the South Staffordshire Coalfield. The sedimentary sequence, principally

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

s and

mudstone Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from ''shale'' by its lack of fissility.Blatt, H., and R.J. Tracy, 1996, ''Petrology.'' New York, New York, ...

s, within the basin is continuous with that of the adjoining basins in the rift complex. Deposition of the Chester Formation (formerly Chester Pebble Beds) for example is ascribed to a river flowing north from the Worcester Basin through the Stafford Basin and on into the Cheshire and East Irish Sea basins during the early Triassic. In contrast the Bridgnorth Sandstone Formation of this area is of aeolian origin, the equivalent of the Collyhurst Sandstone of the Cheshire Basin. The known Permo-Triassic stratigraphic sequence overlying Warwickshire Group strata is thus (uppermost, youngest at top): *

Mercia Mudstone Group The Mercia Mudstone Group is an early Triassic lithostratigraphy, lithostratigraphic group (stratigraphy), group (a sequence of rock strata) which is widespread in Britain, especially in the English Midlands—the name is derived from the ancient ...

* Sherwood Sandstone Group **Helsby Sandstone Formation (=Bromsgrove Sandstone Formation) (

Anisian In the geologic timescale, the Anisian is the lower stage (stratigraphy), stage or earliest geologic age, age of the Middle Triassic series (stratigraphy), series or geologic epoch, epoch and lasted from million years ago until million years ag ...

, Triassic) **---''unconformity''--- **Wildmoor Sandstone Formation (

Early Triassic The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between 251.9 Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which ...

Epoch) **Chester Formation (=Kidderminster Formation, Chester Pebble Beds) (

Olenekian In the geologic timescale, the Olenekian is an age (geology), age in the Early Triassic epoch (geology), epoch; in chronostratigraphy, it is a stage (stratigraphy), stage in the Lower Triassic series (stratigraphy), series. It spans the time betw ...

,Triassic) **---''unconformity''--- **Bridgnorth Sandstone Formation (

Cisuralian The Cisuralian, also known as the Early Permian, is the first series/epoch of the Permian. The Cisuralian was preceded by the Pennsylvanian and followed by the Guadalupian. The Cisuralian Epoch is named after the western slopes of the Ural Mou ...

Epoch, Permian) **---''unconformity''---

References

{{Reflist Sedimentary basins of Europe Geology of Staffordshire Geography of Staffordshire

See also

References