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1: Quartzo-feldspathic mylonite with winged porphyroclast of feldspar indicating dextral movement 
2: Broken up mylonite intruded by pseudotachylyte or friction melt, the result of momentary high temperatures developed during coseismic frictional sliding
The convergence across the Alpine Fault has resulted in the uplift and exhumation of an extensive mylonite zone, formed at depths of 25-30 km. The zone outcrops immediately east of the fault and is up to 1 km wide. A zone of cataclasite and gouge up to 50 m thick bounds the mylonites to the west, and ultramylonite and mylonite grade eastwards into protomylonite and eventually into amphibolite facies Alpine Schist which forms the western flanks of the Southern Alps.
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