Paleoseismic Evidence for 3-5 Earthquakes on the Southern Willunga Fault, South Australia

Paleoseismic trenching across the southern Willunga Fault, approximately 40 km south of Adelaide, reveals evidence for 3-5 ground-rupturing earthquakes since the Middle to Late Pleistocene. Single event displacements range from 0.5 to 1.7 meters, and dating of samples aims to constrain the timing of these events. This investigation, presented at the 2022 Australian & NZ Geomorphology Group Conference, seeks to relate recent uplift to longer-term landscape evolution for improved seismic hazard assessment.

Use Cases

• Estimating recurrence intervals for large earthquakes based on evidence for 3-5 paleoseismic events
• Modeling fault displacement hazard using single event displacements of 0.5–1.7 m
• Relating short-term seismic history to long-term landscape evolution evidenced by uplifted Pliocene basins
• Calibrating seismic hazard assessments for communities and infrastructure near the Willunga Fault

Strengths

• Provides direct paleoseismic evidence for 3-5 ground-rupturing earthquakes
• Quantifies single event displacements within a range of 0.5 to 1.7 meters
• Focuses on a specific fault segment ~40 km south of Adelaide with direct community hazard implications

Limitations

• Description metadata is limited; actual data quality requires manual inspection after download
• Column-level documentation is absent; field semantics must be inferred after download
• Row count is unknown, which may limit suitability assessment

Provenance

Source

Geoscience Australia Data

Collection Method

Paleoseismic investigation involving trench excavation across the fault to examine fault planes and sedimentary strata.

Time Range

Middle to Late Pleistocene to present

Freshness

Last updated 2026-05-14 04:27:11.961688; freshness should be verified

Geography

Southern Willunga Fault, Mount Lofty Ranges, South Australia, approximately 40 km south of Adelaide