Northern Province Chalk nomenclature - Flamborough Chalk Formation

Name

Flamborough Chalk Formation was proposed by Wood and Smith (1978).

Type section

Cliff section between Sewerby Steps and High Stacks, Flamborough Head [TA 201 687 to TA 259 705] (Whitham, 1993; Mitchell, 1994, 1995b).

Reference Section

Atwick No 2 (1973) borehole (TA 15 SE/9) [TA 1835 5171], c. 122 m to c. 385 m.

Formal subdivision

None herein. Divided into three members by Whitham (1993) that are in ascending order the South Landing Member, Danes Dyke Member and the Sewerby Member. There are many named marls units of bed status.'

Lithology

White, well-bedded, flint-free chalk with common marl seams (typically about one per metre). Stylolitic surfaces and pyrite nodules are common.

Definition of upper boundary

Base of lowest flint of succeeding thick, flint-rich unit (i.e. Rowe Formation).

Definition of lower boundary

Top of highest flint band of underlying thick, flint-rich unit of chalk (i.e. Burnham Formation); in type section this is the High Stacks Flint but elsewhere may be at a somewhat different horizon.'

Thickness

The type section, between Flamborough Head and Sewerby, exposes the basal about 160 m of the formation. Equivalent, and probably slightly higher beds (extending up to about 220 m above the base of the formation, according to Whitham, 1993) crop out inland, in the northernmost part of the Yorkshire Wolds, near Driffield. Even higher beds occur beneath drift in the Holderness region where the formation, in boreholes, appears to total about 265 m thick.

Distribution

Known throughout the Northern Province

Previous names

‘Chalk without Flints’ of early Geological Survey maps.

Upper Chalk (pars).

Parent

Chalk Group.

Age and biostratigraphy

Upper Cretaceous, Santonian to Campanian (Gonioteuthis quadrata Zone).

References

Wood and Smith (1978); Whitham (1993); Mitchell (1994).'