The first update to the National Seismic Hazard Assessment of Australia since 2018 has been released by Geoscience Australia. It identifies Darwin and the eastern highlands through into Latrobe Valley as areas where there is a higher risk of strong ground shaking.
A press release by Geoscience Australia said, “Knowing how the ground shaking hazard varies across Australia allows emergency managers, government agencies and the engineering sector to prepare for and respond to, earthquakes in Australia.”
Geoscience Australia senior seismologist Trevor Allen said the new assessment is based on updated data, models, and insights collected from field surveys and earthquake catalogues as well as from people who have felt an earthquake.
Dr Allen said, “We have a large body of information that helps us understand the physical characteristics of earthquakes in Australia and how they impact the landscape around us.”
“Consistent with previous assessments, most areas around Australia are at low to moderate risk of experiencing strong ground shaking. However, our understanding has changed for some regions, such as Darwin and the Victorian high country.”
Dr Allen emphasised that this change in the assessment of risk doesn’t mean earthquakes will happen more often.
“We aren’t getting more earthquakes or stronger earthquakes all of a sudden,” Dr Allen said. “What has changed is how we understand and interpret the risk of earthquakes occurring and their consequent ground motions.
“The new assessment simply clarifies and improves our understanding of the risks that can be associated with this hazard.”
Australia’s seismic hazard profile is low compared to nearby nations such as New Zealand, Indonesia and Papua New Guinea. However, a large proportion of the built environment is vulnerable to earthquake ground shaking –especially masonry buildings that were built before the enforcement of modern earthquake loading standards. A