Magnitude 4.7 earthquake in Wagin, Western Australia

Geoscience Australia’s National Earthquake Alerts Centre (NEAC) recorded an earthquake with a preliminary magnitude of 4.7 at 5.24am AWST in Wagin, Western Australia.

As of 12pm AWST, more than 870 felt reports were submitted by the public via the [email protected] website.

In addition, seven earthquakes with preliminary magnitudes ranging between 2.6 and 3.6 in magnitude have been recorded in the Wagin and Darkan region since 5.44am AWST.

The NEAC has detected more than 70 earthquakes in this region this year, with magnitudes ranging between 2.1 to 4.7.

This phenomenon is what’s referred to as an “earthquake swarm” where a series of moderate-sized “mainshocks” occur in a small area. Each of these so-called mainshocks may have their own aftershock sequences.

In the last five years there have been almost 1200 earthquakes recorded within 200 kilometres of this earthquake. The largest earthquake recorded in this region in the past five years was a magnitude 5.3 at Lake Muir in September, 2018.

General information about earthquakes in Australia

On average, around 100 earthquakes of magnitude 3 or larger are recorded in Australia each year.

Earthquakes above magnitude 5.0, such as the destructive 5.4 magnitude earthquake in Newcastle in 1989, occur around every one to two years.

Approximately every 10 years, Australia experiences a potentially damaging earthquake of magnitude 6.0 or larger such as the Meckering earthquake in October 1968.Compared to countries near tectonic plate boundaries, Australia experiences fewer large earthquakes.

Earthquakes in Australia are caused by the slow build-up of stress in the interior of the continent, produced by the Australian tectonic plate moving approximately 7 centimetres to the northeast every year and colliding with adjacent tectonic plates.

The Australian plate is the fastest moving continental land mass on Earth, colliding into the Pacific plate to Australia’s north and east, and the Eurasian Plate to the northwest.

An earthquake occurs when rocks deep underground break and move along a fault line, releasing this stress.

While some parts of the country are more likely to experience earthquakes than others, large earthquakes can occur anywhere across the continent, and without warning.

In the case of an earthquake, drop onto your hands and knees and crawl under a sturdy table or next to an interior wall, cover your head and neck, and hold on until the shaking stops.

Geoscience Australia’s NEAC uses a permanent network of more than 100 seismic monitoring stations across the country to detect and respond to Australian earthquakes 24 hours a day, 365 days per year.

NEAC also alerts the Australian Government to overseas earthquakes above magnitude 6.0 by drawing on additional real-time seismic data from more than 500 overseas seismometers, operated by various international observatories.

Geoscience Australia also operates the Joint Australian Tsunami Warning Centre (JATWC) with the Bureau of Meteorology. This centre detects, monitors and warns of possible tsunami threats to the Australian coast and offshore territories from large earthquakes 24/7, drawing on a network of hundreds of stations across the globe.

If you felt this earthquake, please lodge a felt report online via the [email protected] website. Your information helps us to understand, and model, the local impacts of Australian earthquakes.

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