Shear-Sense Indicators

Abstract

AbstractA common practice in rocks deformed by shear deformation is to know the sense of shear. This is done by identification of some small-scale structures, called shear-sense indicators that provide the sense of shear of the shear zone. The indicators are developed on all scales ranging from mesoscopic to lattice scales and in practically all rock types. In this chapter, we have described some common shear-sense indicators developed in rocks deformed by both ductile and brittle deformations. Although shear-sense indicators indicate the sense of movement during deformation, studies reveal that the practice may sometimes lead to misleading results by providing opposite sense also. This phenomenon is called opposite shear sense.KeywordsShear-sense indicatorsDuctile shear-sense indicatorsQuartz CPOBrittle shear-sense indicatorsOpposite shear sense