Abstract
Fluids played an important role in the emplacement of the Esla thrust causing local epigenetic dolomitization of the thrust sheet base. Thrust slip aided by an overpresured fluid, at the Upper Devonian sandstone level, took place initially by seismic events that caused grain size reduction, forming cataclasites and injected detritic quartz grains in the fault zone. Cataclastic flow during stable slip caused concentration of slip on P-type fractures producing a cataclastic foliation. Continuous slip caused accomodation of slip on Y-fractures that gave the foliation an orientation parallel to the thrust surface.
