A statistical approach to determination of a mineral lineation

A statistical model of the bipolar von Mises type was applied to the analysis of mineral lineation defined by the preferred dimensional orientation of inequant grains on a foliation surface. Orientation data of 203–258 grains from each of four rock specimens fit the model well, suggesting a useful analytical technique with three advantages: (1) confidence in whether a metamorphic tectonite has a mineral lineation can be determined using a χ2-test, (2) the orientation of the mineral lineation can be represented by the mean direction (θ̄) with a specified confidence interval, and (3) the degree of preferred dimensional orientation of grains can be quantified by the concentration parameter (κ̂).