When epitaxy controls garnet growth

摘要: Within a mica schist from the coesite-bearing Brossasco-Isasca Unit (Western Alps), microstructural analysis shows that Alpine garnet grains are aligned with crenulated foliation. Garnet crystallographic orientation was analysed electron backscatter diffraction (EBSD): obtained dispersion patterns and distribution of misorientation axes suggest strong parallelism {110} planes 56°W-dipping The data interpreted as evidence for an epitaxial growth upon (001) biotite planes, sometime during and/or after biotite/garnet crystals their initially foliation-parallel by rotation about crenulation axis. This interpretation is based on comparison measured EBSD with: (i) theoretical trajectories data, (ii) numerically modelled pole figures, (iii) axis patterns. Our allowed distortion pseudohexagonal basal oxygen ring structure surfaces, driven introduction missing ions. further spatial precursor phases influences within schists.