Summary of Characteristics of Australian Earthquakes Intraplate, so they are infrequent A person feels an event only every 5 -10 years. One of the most active intraplate areas. Low maximum magnitude, perhaps Mw 7.5. Hazard is widely distributed. Small events often felt and heard.
Moderate magnitudes can cause damage.
Above Mw 6 usually gives surface rupture. Usually horizontal compression Reverse faults predominate. High stress drop, giving high amplitude, high frequency, short duration motion. The old, cold, hard rocks of Western and Central Australia do not absorb seismic energy greatly, so earthquakes in these areas are felt over longer distances than in Eastern Australia.