Figure F113. Greenschist-facies breccias and shear zones. A. Tremolite schist clast (pale green) in breccia consisting of metabasalt fragments in an actinolite-rich sheared matrix (Sample 304-U1309B-3R-1, 80–82 cm) (field of view [FOV] = 4.1 cm). B. Chromite at the edge of the tremolite schist clast (as seen in A), suggesting an ultramafic origin, together with the actinolite-rich breccia matrix and a clast of altered basalt (plane-polarized light; FOV = 5.1 mm). C. Actinolite-rich breccia zone cutting altered gabbro with plagioclase-rich veins of probable igneous origin (Sample 304-U1309B-7R-1, 0–16 cm) (FOV = 7.3 cm). D. Detail of cataclastic actinolite zone at the edge of the gabbro, showing plagioclase with a fresh core altering to albite and cut by stringers of actinolite (Sample 304-U1309B-7R-1, 6–8 cm) (plane-polarized light; FOV = 1.3 mm). E. Porphyroclast of pale amphibole folded in an extremely fine grained actinolite shear zone (Sample 304-U1309B-7R-1, 67–69 cm) (plane-polarized light; FOV = 2.6 mm). F. Euhedral zircon crystals (probably inherited from the protolith) surrounded by albite + chlorite/actinolite after plagioclase in gabbro. Note the presence of both brown and green amphiboles (Sample 304-U1309B-7R-1, 6–8 cm) (plane-polarized light; FOV = 1.3 mm).
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