Computer Code: |
STEL |
Preferred Map Code: |
StrT |
Status Code: |
Full |
Age range: |
Neoproterozoic Era (AZ)
— Neoproterozoic Era (AZ) |
Lithological Description: |
Interbedded psammite and quartzite units, mostly thickly-bedded, with internal features suggesting deposition in a shallow marine shelf environment. |
Definition of Lower Boundary: |
Gradational boundary with Bruar Psammite Formation at base of Tummel Quartzite Formation. |
Definition of Upper Boundary: |
Sharp, conformable boundary at top of Kynachan Psammite Formation with Dunalastair Quartzite Formation (Lochaber Subgroup, Appin Group). |
Thickness: |
1000 - 3800m on limbs of Meall Reamhar Synform; lower limit probably involves tectonic thinning, but upper limit may involve tectonic thickening. |
Geographical Limits: |
From closure of Errochty Synform [NN 710 671] north-east to A9 road near Dalnamine [NN 750 700, then due east to Loch Tay Fault at [NN 880 700], then along Loch Tay Fault to Loch Tummel [NN 802 598], and thence back to the closure of the Errochty Synform via the northern boundary of the Dunalastair Formation. Possible extension of this area to north-west not defined. |
Parent Unit: |
Grampian Group (GRAM)
|
Previous Name(s): |
Strathtummel Succession [Obsolete Name and Code: Use STEL]
(-3053)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Section |
Type section of Tummel Psammite Formation. South side of River Tummel and Dunalastair Reservoir from weir below Dunalastair Dam. |
Type Section |
Type section of Kynachan Quartzite and Kynachan Psammite formations. South side and main ridge of Creag Kynachan. |
Reference(s): |
Treagus, J E. 2001. Solid geology of the Schiehallion district. Memoir of the British Geological Survey, Sheet 55W (Scotland). |
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. |
Thomas, P R, 1980. The stratigraphy and structure of the Moine rocks north of the Schiehallion Complex, Scotland. Journal of the Geological Society, London, Vol.137, 469-482. |
Stephenson, D and Gould, D. 1995. British Regional Geology: the Grampian Highlands (4th edition). (London: HMSO for the British Geological Survey), 67-68. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
S055
S055
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