Feeling the quake kilometres away
PREDICTIONS that parts of the Gympie region will feel the effects of a potentially destructive earthquake in the near future are not so far fetched.
Parts of north Queensland were shaken on April 16 by two moderate earthquakes within an hour of each other, measuring 5.2 and 4 on the Rictor scale – the state’s strongest since 1965.
It is believed the last tremor reported in the Gympie region was widely felt at Wonga Valley on April 30, 1998.
Last Saturday’s quake was recorded 60 kilometres west of Bowen just after 3.30pm last Saturday, with tremors felt in several towns throughout the region.
Similar earthquakes were recorded in the same area in 1989 and 1990.
Western Australia experienced the largest earthquake in its history in April last year, following a tremor registering about 4 in Adelaide.
In fact Australia experiences several earthquakes each year, most too weak to be felt by residents.
Geoscience Australia seismologist David Jepsen said recent earthquakes were unrelated to tremors that devastated areas in New Zealand and Japan.
Australia has what seismologists call “intraplate earthquakes” across the continent – a release of stress that builds up in the crust due to the continent’s tectonic movement in the north.
Earthquakes just over a magnitude 6 hit off Gladstone and Gayndah in 1918 and 1935, the latter tremor felt in Gympie but the shock was most severe in the Wondai district with homes and farm buildings rocked by a tremor that lasted 13 seconds.
More than 80 after shocks followed.
Since 1935 many shocks have been recorded in the state, including two shocks in Maryborough in 1947 and 1952.
To date, the most destructive earthquake recorded in Australia was in Newcastle, New South Wales, December 1989.
There were 13 fatalities, 160 hospitalised, 50,000 damaged homes, and 300 buildings demolished.
Now one of the state’s leading seismologists says Queensland is due to experience a potentially destructive earthquake in the near future.
Central Queensland Seismology Research Group leader Mike Turnbull has warned significant seismic activity was predicted for Queensland in coming years.
“About every 130-year period we can expect to have at least one magnitude 6 earthquake somewhere in central Queensland,” Mr Turnbull said.
Did you know?
In Australia, an earthquake of Richter magnitude 5.5 (ie: almost that of the Newcastle event in 1989) occurs every 15 months on average.
90% of all earthquakes in the world take place at plate boundaries and are the result of the constant movement of the plates against each other.
The geographically-oldest western and central parts of Australia are most seismically active.
The 1989 Newcastle Earthquake has been Australia’s most damaging earthquake with 13 fatalities and insured damage of $1,124 million.
The most deadly earthquake was recorded in China in 1557.
During this time many people lived in the mountains in artificial caves and the quake resulted in more than 800,000 deaths.
* taken from the Emergency Management Australia website