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
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 
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: