Computer Code: |
NORH2 |
Preferred Map Code: |
SYMBOL |
Status Code: |
Full |
Age range: |
Cambrian Period (E)
— Cambrian Period (E) |
Lithological Description: |
A green hornblende-rich schist with an S-tectonite fabric, which commonly has fine closely-spaced feldspar-rich laminations. At Virva, it grades into greenschists of volcanic origin. |
Definition of Lower Boundary: |
A tectonic slice, having a faulted base. |
Definition of Upper Boundary: |
A tectonic slice, having a faulted base. |
Thickness: |
A tectonic slice up to several hundred metres thick. |
Geographical Limits: |
Occur in several locations in Fetlar - most outcrops are of limited extent up to 1 km long and up to several hundred metres wide. |
Parent Unit: |
Shetland Ophiolite Complex (SHOP)
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Previous Name(s): |
none recorded or not applicable
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Alternative Name(s): |
none recorded or not applicable
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Stratotypes: |
Type Area |
Virva section on NE coast of Fetlar. Flinn, 1993. |
Reference(s): |
Flinn D. New evidence that the high temperature hornblende-schists below the Shetland ophiolite include basic igneous rocks intruded during obduction of the 'cold' ophiolite. 1993. Scottish Journal of Geology, 29 [2], 159-65. |
Flinn, D, Miller, J A and Roddom, D. 1991. The age of the Norwick hornblendic schists of Unst and Fetlar and the obduction of the Shetland ophiolite. Scottish Journal of Geology, 27 (1), 1-80. |
Read H H. 1934. The metamorphic history of the Unst in the Shetland Islands Quarterly Journal of the Geological Society of London, 90, 637-88. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
S131
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