Burcot Member

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Burcot Member (BRCT)

Burcot Member (Old et al. 1991)

Previous nomenclature

Basement Beds (Hull, 1869)

Parent unit

Helsby Sandstone Formation

Derivation of name

From the Burcot area (SO 98 71), Worcestershire

Type section

Road cutting, Burcot (SO 972 716) (Benton et al. 2002)

Reference section

SO 9619 6816: Sugarbrook No. 3 Borehole BGS Registered No. SO96NE/30, 206.8 to 398.4 m (Old et al., 1991); the base of the member was not proved.

Extant exposures/sections

Scattered exposures south of Kidderminster, Worcestershire.

Lithology

The dominant lithology is planar and trough cross-bedded, irregularly bedded and structureless red-brown sandstones. Subordinate lithologies are conglomerates composed of subrounded to angular clasts. Extraformational clasts include quartz, quartzite, limestone, chert and tuff; intraformational clasts include mudstone, siltstone and sandstone. There are subordinate beds of grey-green mudstone and siltstone. The sequence shows repeated fining-upward cycles, from conglomerate to mudstone; the siltstone and mudstone components of these are commonly absent. Sedimentary structures include ripple marks, flute casts, slump structures and convolute bedding. Micaceous bedding planes are common. A solitary fish spine was recorded from the member (Wills, 1970).

Lower boundary

The lower boundary is taken at the lowest conglomerate resting on soft red sandstones of the Wildmoor Sandstone Member of the Wilmslow Sandstone Formation.

Upper boundary

The upper boundary is taken at the top of the highest bed of extraformational conglomerate, above which are sandstones and mudstones of the overlying Finstall Member.

Thickness

The thickest known sequence is 192.4 m, in the Sugarbrook No. 3 Borehole, but the base has not been proved.

Age

Anisian (early Mid Triassic)

Equivalent units

None

Geographical extent

The member has only been mapped in the Bromsgrove area of Worcestershire but is likely to extend westwards to Little Witley [SO 78 63], Worcestershire.

Subdivisions

None

References