Middle tertiary hydrothermal activity and uplift of the northern flinders ranges, South Australia: Insights from apatite fission-track thermochronology

Abstract

Apatite fission-track thermochronology reveals that hydrothermal activity was pervasive during mid-Tertiary time within the Paralana Fault zone and adjacent country rocks of the northern Flinders Ranges, South Australia. Apatite fission-track ages from the Mt Painter block, west of the Paralana Fault zone, range between ˜ 175 and 260 Ma. The mean lengths of confined fission-tracks for these samples are ˜ 12 μm with s.d. of the track length distributions of ˜ 2 μm. These data suggest that rocks exposed in the Mt Painter block cooled slowly though the apatite partial annealing zone (˜ 110-50°C) starting before 200 Ma and continuing into the Tertiary. In contrast, apatite samples from the Paral..