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The photograph shows the youngest strand of the Alpine Fault in Hare Mare Creek, looking southwards; the light coloured zone at the top of the face of gravel is the hydrothermally altered basal cataclasite - here this is c. 3m thick and is overlain by a sequence of fractured mylonites. Beneath are steeply dipping fluvio-glacial gravels approximately 15-20,000 years old.
This area is a complex zone of oblique thrusting on the Alpine Fault, with sheets of mylonite thrust up to 2 km westwards over Quaternary gravels. "Out of sequence" imbrication of the fault and complex internal deformation of the thrust sheets is related to rapid erosion by the Waikukupa River following glacial advances.
- Norris, R. J. and Cooper, A. F., 1997