- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
A chevron-folded phyllite composed of well contrasted quartzose and micaceous layers was examined [at Bigbury-on-Sea, Devonshire, England]. The false cleavage in the mica layers is of fan type and measurements show a correlation between the angle of the fan and the thickness of the layer in which it forms. Such a correlation is to be expected if the folds formed by buckling under lateral compression.