| Computer Code: |
FHL |
Preferred Map Code: |
notEntered |
| Status Code: |
Pending Upgrade |
| Age range: |
Arundian Substage (CJ)
— Arundian Substage (CJ) |
| Lithological Description: |
Dark grey, medium-bedded skeletal limestones with thick-bedded, locally cross-bedded, commonly ooidal limestones at base. Units of interbedded dolomite mudstone, dolomite siltstone and mudstone punctuate the succession. Deposited as a transgressive barrier and offshore shelf sequence. |
| Definition of Lower Boundary: |
Taken at the sharp erosive contact of the massive to thick-bedded pale grey skeletal and ooidal limestones of the Flatholm Limestone Member and the thin- to medium-bedded dolomite and calcite mudstones and mudstones of the underlying Caswell Bay Mudstone Formation. |
| Definition of Upper Boundary: |
Taken at the top of the uppermost unit of the interbedded dolomite mudstone, dolomite siltstone and mudstone of the Member, which is overlain by massive to thick-bedded pale grey skeletal and ooidal limestones of the remaining part of the High Tor Limestone Formation. |
| Thickness: |
31m |
| Geographical Limits: |
Flat Holm Island [ST 22 64], South Wales. |
| Parent Unit: |
High Tor Limestone Formation (HTL)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Cliffs and foreshore reefs on the east coast of Flat Holm island between Dripping Cove and Lighthouse Point. Entire section [31m] seen and comprises skeletal and ooidal limestones punctuated by units of dolomite mudstone. Lower contact with the Caswell Bay Mudstone Formation and upper contact with the undivided High Tor Limestone Formation seen. |
| Reference(s): |
| Whittaker A and Green G W. 1983. Geology of the country around Weston-super-Mare. Memoir of the Geological Survey, England and Wales, Sheet 279 with parts of sheets 263 and 295. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E263
E279
|
