Formation process of microstructures developed on the Glarus thrust

Abstract

In this study, microstructural observations of slickenside developed on Glarus thrust in the Swiss are performed, in order to understand its formation mechanism. Slickenside widely develops on Lochseiten calk (LK) in Glarus thrust. The summery of our microstructural observation is followings. 1) Periodical faulting occurred along LK. Plastic deformation of calcite grains proceeded in term between these faulting. 2) Fault slip occurred initially along the wide area, ca. 1 cm, from slip surfaces. Then it was concentrated toward to the slip surface, and was finally limited along the narrow area less than 100 nm, which corresponded to the slickenside.