North Queensland has been struck by a magnitude 4.8 earthquake, Geoscience Australia has reported.
At 1 pm about 80 kilometres south of Charters Towers at a depth of 10 kilometres the earthquake, originally reported at magnitude 4.9 but later downgraded.
Within 45 minutes more than 300 messages came to Geoscience Australia from people saying they felt the earthquake, including those in Townsville as far as 180 kilometres.
Geoscience Australia Seismologist Spiro Spiliopoulos said people had reported experiencing “vibrations” as a result of the earthquake and heard “rattling,” but no reports of damage were confirmed.
Rebecca Mills, who lives in Aitkenvale’s Townsville suburb, said it was “very quick” and lasted “just a couple of seconds”, but “shook my house.”
Mr Spiliopoulos said earthquakes were a natural occurrence that happened over time due to stresses in the Earth but were “not common” in Queensland.
Mr Spiliopoulos said Geoscience Australia records showed 47 earthquakes have occurred in the 200-kilometer radius around Sunday’s tremor since 1950.
According to the Geoscience Australia website, a magnitude 5 earthquake is “moderate” and likely to cause: “Some dishes, windows broken. Unstable objects overturned. Pendulum clocks may stop.”
“The size or magnitude of earthquakes is determined by measuring the amplitude of the seismic waves recorded on a seismograph and the distance of the seismograph from the earthquake,” the site says.
“These are put into a formula which converts them to a magnitude, which is a measure of the energy released by the earthquake.
“A magnitude 8.6 earthquake releases energy equivalent to about 10,000 atomic bombs of the type developed in World War II.
“Fortunately, smaller earthquakes occur much more frequently than large ones and most cause little or no damage.”
— Bureau of Meteorology, Australia (@BOM_au) August 23, 2020