The BGS Lexicon of Named Rock Units — Result Details

Norwick Hornblendic Schist Type 1

Computer Code: NORH1 Preferred Map Code: SYMBOL
Status Code: Full
Age range: Cambrian Period (E) — Cambrian Period (E)
Lithological Description: Albite-porphyritic metablast, locally deformed to a phyllite.
Definition of Lower Boundary: Tectonic base - imbricate thrust zone.
Definition of Upper Boundary: Tectonic top - imbricate thrust stack.
Thickness: Unknown.
Geographical Limits: The main mass is about 1.5 km long and extends inland from Norwick, a small lens crops out on the coast at The Clifts, Norwick, Unst
Parent Unit: Shetland Ophiolite Complex (SHOP)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Poorly exposed in ditches and stream beds around the Norwick area and at the base of the sea cliff at the Clifts, Norwick, Unst. Flinn, 1993 
Reference(s):
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. 
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. 
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