Figure F70. Cataclastic foliation, Sample 345-U1415J-21R-1, 17–19 cm (Piece 4). A. Macroscopic rotation of cataclastic foliation into fine-grained zones, microfaulting, and asymmetric prehnite porphyroclasts. B. Microstructure of well-developed cataclastic foliation defined by anastomosing ultrafine-grained dark to light brown layers (clay?) separated by lenses hosting porphyroclasts of plagioclase, prehnite, epidote, clinozoisite/zoisite, and carbonate. Red box indicates location of C. C. Asymmetric prehnite porphyroclasts (“fish”) showing undulose extinction and subgrain formation, hosted in a sheared chlorite matrix. Although sense-of-shear indicators are recognized in thin section, none of the recovered pieces hosting these microstructures are oriented; therefore, no shear sense was determined. Under crossed polars.
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