Burcot Member

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Burcot Member (BRCT)[edit]

Burcot Member (Old et al. 1991)

Previous nomenclature[edit]

Basement Beds (Hull, 1869)

Parent unit[edit]

Helsby Sandstone Formation

Derivation of name[edit]

From the Burcot area (SO 98 71), Worcestershire

Type section[edit]

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

Reference section[edit]

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[edit]

Scattered exposures south of Kidderminster, Worcestershire.

Lithology[edit]

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[edit]

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[edit]

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[edit]

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

Age[edit]

Anisian (early Mid Triassic)

Equivalent units[edit]

None

Geographical extent[edit]

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[edit]

None

References[edit]