Layered gabbro sheared under granulite-facies conditions. The tectonic foliation is nearly parallel to the primary compositional layering. White layers are anorthositic; dark layers are hornblenitic and layers with intermediate color index are gabbroic to gabbro-noritic. A brown-weathered Opx porphyroclast occur in the central hornblendite layer.
PhotoID443
Layered gabbro sheared under granulite-facies conditions. The tectonic foliation is nearly parallel to the primary compositional layering. White layers are anorthositic; dark layers are hornblenitic and layers with intermediate color index are gabbroic to gabbro-noritic. A brown-weathered Opx porphyroclast occur in the central hornblendite layer.
PhotoID443
Photograph: Ivan Zibra
Reference: Reference: Zibra I, Kruhl JH, Braga R (2010). Late Palaeozoic deformation of post-Variscan lower crust: shear zone widening due to strain localization during retrograde shearing. Int J Earth Sci (Geol Rundsch) DOI 10.1007/s00531-009-0441-5