0 a type of metamorphic rock that contains light and dark layers formed of minerals such as quartz and mica --
In thin-sections, the gneisses are cut by narrow pressure solution seams and narrow cataclastic shear zones.
However, few recognizable trends are apparent within the data clusters for the siliceous gneisses.
There is a continuum apparent between the amphibolites and intermediate gneisses, whilst the felsic gneisses form a separate, high-silica group.
To the south, the meta-gabbro is bounded by felsic gneiss.
The kinematic evidence is interpreted to mean that the contact between the gneiss and the biotite schist has a normal-shear (hangingwall down) geometry.
These pass up into a 150 m thick homogeneous granite that is bound by planar surfaces parallel to the foliation in the underlying gneiss.
In general, eclogites are predominantly mafic and are preserved as boudins within felsic gneisses.
These gneisses have been multiply deformed at granulite-facies conditions.