An orthogneiss with a composition of plagioclase
(40%), K-feldspar (25%), quartz (25%), chlorite (5%), muscovite (2%),
epidote (2%), and trace sphene and oxides, sample 03MW2622 shows less
evidence of metamorphism than most of the other gneissic samples. 8-mm
plagioclase porphyroclasts are visible in hand sample. Micas occur in
0.5-1 mm-thick bundles, yet no deformational fabrics are recognized. |