Proceedings of the 12th International INQUA meeting on paleoseismology, active tectonic and archaeoseismology

232 PATA Days 2024 In this study, preliminary results of paleoseismic investigations of the Jindabyne Thrust and the adjacent Hill Top Fault are presented, providing constraints on the timing and magnitude of past earthquakes. Four trenches were excavated across the Jindabyne Thrust at East Jindabyne, and one trench was excavated across the Hill Top Fault near Rushes Creek (Figure 3, Figure 4, Figure 5). The Jindabyne Thrust The Jindabyne Thrust is a reverse fault that runs for approximately 120 km in a roughly N-S direction, dipping to the east (Figure 2, Figure 3, Figure 4). In the study area the fault runs along the eastern shoreline of Lake Jindabyne, where it offsets Silurian intrusive rocks. West-facing scarps associated with the fault cut across hillslopes and are clearly visible in a LiDAR DEM and in the field (Figure 4). In places the fault offsets Quaternary-age alluvial fans where these emerge from catchments within the range to the east, providing evidence that the fault is active in the current stress regime. The fault links with the Barneys Range Fault to the south and the Hill Top, Berridale Wrench, Boggy Plain and Tantangara faults to the north. The Jindabyne Thrust is thought to be one of Australia’s most active onshore faults, with an estimated long-term geological slip rate of 117 m/Ma (Clark et al., 2016; Clark, 2023). However, Fig. 3: Hillshaded LiDAR DEM overlain by fault scarps (red lines) mapped from the LiDAR DEM.