Computer Code: |
DBDQ |
Preferred Map Code: |
DuQu |
Status Code: |
Full |
Age range: |
Neoproterozoic Era (AZ)
— Neoproterozoic Era (AZ) |
Lithological Description: |
Quartzite, massive to blocky, locally feldspathic. Micaceous quartzite at base in southern part of outcrop. |
Definition of Lower Boundary: |
Change from interbedded psammite and semipelite of Arnbath Formation, where present, or pelite and limestone of Fordyce Limestone Formation, to thicker-bedded quartzite. |
Definition of Upper Boundary: |
Rapid transition to pelite (graphitic near coast) at base of Castle Point Pelite Formation. |
Thickness: |
c.400m on Durn Hill, thinning to c.150m at coast. Probably repeated by folding and thrusting on Knock Hill and farther south. |
Geographical Limits: |
Coast section from 150m southeast of Foul Hole to John Legg's Well [NJ 579 666 to 580 665]; extends southwards as far as Braco [NJ 498 512]. Equivalent to the Kymah Quartzite farther south. |
Parent Unit: |
Islay Subgroup (DBIS)
|
Previous Name(s): |
Upper part of Durn Hill Quartzite [Obsolete Name and Code: Use DBDQ]
(-4588)
|
Alternative Name(s): |
Kymah Quartzite Formation
|
Stratotypes: |
Reference Section |
Coastal section from 150m southeast of Foul Hole to John Legg's Well. |
Partial Type Section |
Durn Hill Quarry. |
Reference(s): |
Stephenson, D and Gould, D. 1995. British Regional Geology: the Grampian Highlands (4th edition). (London: HMSO for the British Geological Survey), 67-68. |
Harris, A L, Haselock, P J, Kennedy, M J and Mendum, J R, 1994. The Dalradian Supergroup in Scotland, Shetland and Ireland. 33-53 in Gibbons, W E and Harris, A L (editors). A revised correlation of Precambrian rocks in the British Isles. Special Report of the Geological Society, London, No.22. |
Read, H H, 1923. Geology of the country around Banff, Huntly and Turriff, Lower Banffshire and north-west Aberdeenshire. Memoir of the Geological Survey, Scotland Sheets 86 and 96 (Scotland). |
Stephenson, D, et al. 1993. Stratigraphy and correlation of the Dalradian rocks of the East Grampian Project area. British Geological Survey Technical Report WA/93/91. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
S096
S086
|