Seismology Research Centre

@earthquakes.au

Earthquake Observatory in Melbourne, Australia, monitoring events in the southeastern states. Seismograph manufacturer. Media contact: @SeisLOLogist

Here's a map of the last week of earthquakes up to midnight Sunday UTC time (10am AEST today). Based on data from 38 stations, we've recalculated this morning's earthquake near Broadford as a magnitude 3.0. Despite the 1:14am origin time, almost 300 people reported feeling it, up to 80km away.

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The SRC detected 42 earthquakes last week, 7 of which were over magnitude 2. The largest was a magnitude 2.9 northeast of Gladstone, SA. A lot of folks ask us how they can find out more about individual events on our maps. We will soon be releasing an app to allow you to do just that. Stay tuned!

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The two largest earthquakes last week were in Victoria: a magnitude 2.3 earthquake occurred near Rushworth at 12:54pm on the 4th of August, at a depth of 11km; and a magnitude 2.6 earthquake occurred the following day at 9:01am, located near Yallourn, at a depth of 18km.

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All earthquakes last week were below magnitude 2, which we expect were all too small to be felt, particularly as their average depths were 9km, ranging from near-surface to 20km deep. Three earthquakes occurred near Korumburra VIC, an area that has hosted several magnitude 4+ events in recent years.

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The largest earthquake in the region last week was a magnitude 3.0 north of Dubbo, NSW. It struck at 5:31am on 22 July. The magnitude 1.9 near Sydney was in the Kamay Botany Bay National Park, near Cronulla at 2:13pm on 21 July.

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Just 28 earthquakes detected last week in our monitoring area. Yes, EARTHQUAKES. No magnitude-shaming here! People refer to small earthquakes as "tremors", a medical term related to involuntary muscle movement. We do too sometimes, but you can't deny they're all earthquakes, no matter how small ☺️

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32 earthquakes detected in a week is close to the average for our map area. Note that a magnitude 2.1 is hiding under that 1.8 near Muswellbrook NSW. We're often questioned about these earthquakes as they don't appear on GA's online map. GA only publish small events if they are likely to be felt.

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Yesterday's MLv4.0 earthquake, SW of Lavers Hill in Victoria's Otway Ranges, occurred at a depth of 20km, which may explain why it wasn't as widely felt as an earthquake of this magnitude would normally be. This earthquake was about 25x larger than the next biggest, a 2.6 in SA's Flinders Ranges.

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Another 39 earthquakes added to the catalogue. The largest last week was a magnitude 2.2 off Port Campbell in Victoria, followed only an hour later by an unrelated magnitude 2.1 that occurred just south of Woodford in the Blue Mountains, west of Sydney NSW.

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Four M3+ earthquakes in a single week for our monitoring area is unusual, but the time and distance between them means they are unlikely to be related. The largest was a magnitude 3.5 at Cadia NSW. The other 3.0 in NSW was about 50km northeast of Dubbo, with a 3.0 and 3.2 in SA's Flinders Ranges.

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Of the 63 earthquakes that occurred in southeast Australia over the last fortnight, eight were over magnitude 2. The largest two were both magnitude 2.8, one on June 6th at 6:26am off the NSW south coast, and the other on the 14th at 12:51pm under Blowering Reservoir in southern NSW.

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The two magnitude 2.1 earthquakes in Tasmania last week were about 42 hours apart and located near Rosebery and Renison Bell. The largest earthquake last week was only slightly larger at M2.3, located off Sandy Point in Victoria.

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Detecting 36 earthquakes in a week is pretty close to average for our monitoring region in southeast Australia. Three earthquakes just crept into the magnitude 2 range: one north of Balranald NSW, one east of Burra SA, and another west of Arkaroola SA.

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Here's the last 2 weeks of earthquake activity covered by our monitoring network in Australia's southeast. The largest earthquake was a magnitude 3.4 near Dumbalk in Victoria, and the eight magnitude 2.0-2.9 spread across the states contributed to a total of 83 earthquakes for the fortnight.

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There was a little magnitude 1.8 south of Wodonga on the VIC-NSW border at 6:34pm tonight. Something this small is not usually noteworthy, but we had a report that the it was enough to bring entire streets of people out of their homes for what they thought were explosions.

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A magnitude 3.6 earthquake occurred near Hawker in South Australia last week and was the largest of 27 earthquakes detected. Each state hosted at least one magnitude 2 event: a 2.8 near Dumbalk VIC, a 2.8 off Kiama NSW, and a 2.2 near Rosebery TAS. The 2.0 near Adelaide was east of Willunga SA.

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Another 33 earthquakes were added to the catalogue last week. The little cluster in Tasmania was between Lake Pedder and Lake Gordon. The biggest event for the week was only magnitude 2.4, located about 140km north of Broken Hill in NSW.

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The largest earthquake last week was a magnitude 4.6 on the 14th of April, located at Cadia in NSW. It was felt across the state to distances of over 300km. It's the largest earthquake ever recorded in the area, the next largest being a magnitude 4.2 in 2017, coincidentally also on 14 April (AEST)

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This map shows 2 weeks of earthquake activity in southeast Australia from 30 March to 12 April. The two largest of these 44 quakes were off Victoria's southeast coast - a magnitude 2.7 off Seaspray, and a 2.4 off Cape Patterson. In NSW both Mt Thorley and Broken Hill experienced magnitude 2.1 events

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