Crystal size distribution analysis of quartz in sector- zoned of garnet schist using Back-scatter electron images

Abstract

The studied sample presents garnet textural sector-zoning as inclusions in two types in garnet schist from Morlaix, North-West Brittany, France. Crystal size distributions (CSD) of quartz crystals were measured in both types inclusions, in the matrix and strain shadows around garnet porphyroblasts using Back-scatter electron (BSE) images. The CSD plots of quartz crystals show an increase of average in sizes from type 1 inclusion,60mm, to the matrix,116 mm, and strain shadow,248 mm,. These differences could be explained of quartzes size distribution by many processes such as capturing by pophyroblast, crystal face, annealing and grain boundary migration 

Keywords


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