The electron backscatter diffraction (EBSD) analysis procedure for crystal preferred orientations to reduce loss of EBSD map data: An example of antigorite

Indexing Kikuchi or electron backscatter diffraction (EBSD) patterns from rock samples provides information on mineral phases and their crystal orientation and maps of this information are widely used for mineral microstructural analysis.However, uncertainties in the results due to possible problems of mis-indexing have not been closely studied.One approach to identify unreliable data is to use a filter based on maximum mean angular deviation (MAD) values.Mechanically weak minerals, in particular hydrous sheet silicates, are particularly challenging to analyze due to surface damage formed during sample preparation and electron beam irradiation.The application of stringent MAD filters to extract high-quality accurate data for minerals such as antigorite drastically reduces the proportion of data that can be used for analysis in particular in surfaces cut perpendicular to rock foliation.