Computer Code: |
HGMS |
Preferred Map Code: |
notEntered |
Status Code: |
Index Level |
Age range: |
Eifelian Age (DI)
— Givetian Age (DV) |
Lithological Description: |
[Obsolete: use HASA] Quartzitic sandstones, locally coarse or conglomeratic, some slates. Colours red, green, variegated. Rare plant remains marine fossils at upper boundary. |
Definition of Lower Boundary: |
Drawn at the base of the Triscombe Beds where it rests conformably upon the Lynton Beds. |
Definition of Upper Boundary: |
Drawn at the conformable upward passage from the Sherry Combe Beds to the Ilfracombe Beds. |
Thickness: |
1219m approx. |
Geographical Limits: |
North Devon, England. |
Parent Unit: |
none recorded or not applicable
|
Previous Name(s): |
Hangman Grits [Obsolete Name And Code: Use HASA]
(HAG)
|
Alternative Name(s): |
Hangman Sandstone Formation
|
Stratotypes: |
Type Area |
Hangman Hill to Martinhoe, east of Combe Martin, North Devon. |
Reference(s): |
House, M R, Richardson, J B, Chaloner, W G, Allen, J R L, Holland, C H and Westoll, T S. 1977. A Correlation of Devonian rocks of the British Isles. Geological Society of London, Special Report No.8, Scottish Academic Press, Edinburgh. |
Evans, J W. 1922. The geological structure of the country round Combe Martin. Proceedings of the Geologists' Association, Vol.33, 201-228. |
Hallam, A D, 1934. The geology of the Hangman Grits of the Quantock Hills. Geological Magazine, Vol.71, p.433-446. |
Etheridge, R. 1867. On the physical structure of west Somerset and north Devon and on the palaeontological value of the Devonian fossils. Quarterly Journal of the Geological Society of London, Vol. 23, p.568-698. |
Sedgwick, A and Murchison, R I, 1836. A Classification of the old slate rocks of North Devonshire. British Academy for the Advancement of Science, Report No.5, p.95. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |