The contouring of orientation data represented in spherical projection

Abstract

The inadequacy of the current method of contouring orientation data in terms of the concentration of points occurring in 1% of the projected area is demonstrated. In particular, the maximum concentration and the areas occupied by the different concentrations are shown to be dependent on sample size. Using a counting area of 100/n% of the projection, where n is the sample size, yields meaningful orientation patterns which are comparable for different sample sizes. This is illustrated with reference to computer generated random and non-random orientation patterns. The data obtained are compared with predicted values and form a basis for comparison with measured orientation patterns to test their significance.