Texture Analysis of Quartz in a Granite Mylonite byEBSP‐Orientation Imaging Microscopy

The crystallographic preferred orientation (texture) of the quartz phase in a myloniticleucogranite from the Santa Rosa mylonite zone was investigated using automatedanalysis of electron backscattering patterns (EBSP) in the scanning electron microscope(SEM). The separation of the quartz diffraction patterns from patterns of other constituents(feldspar, mica, etc.) in this polymineralic rock was achieved using an imagequality parameter. The quartz phase displays a texture typical for high temperaturemylonites ( c -axis maximum in the intermediate strain direction). The misorientationdistribution between next neighbors is dominated by Dauphiné twins.