Earthquake in Melbourne, Australia (9.15 AM 22nd Sep 21, AEST)

https://earthquakes.ga.gov.au/event/ga2021sqogij

by jp0d • 5 years ago

73 83 5 years ago

earthquakes.ga.gov.au

Felt this as far away as Wagga Wagga, NSW. It's insane how far these things travel, and especially a shock in a place like Australia where Geological activity is so low. We're just not used to this kind of thing

shirro2• 5 years ago

Never knew how far earthquakes travelled. I guess everyone else on the planet knows but I didn't realise you could feel them in a different state until today. And this wasn't even a big one compared to what they get all the time in places like NZ or Japan. Nature is awesome.

monkeycantype• 5 years ago

A medical researcher I study with though she was experiencing the onset of Parkinson's

kadoban• 5 years ago

Looks far enough away to not have caused anything too serious in Melbourne. Is there anything much closer to the epicenter there that would be harder hit?

The few early news articles I can find seem to confirm not much serious damage in Melbourne.

JanisL3• 5 years ago

Not much damage in Melbourne, at least so far (hopefully nothing bigger happens, this comment is a couple of hours since the main shock). A few poorly built brick walls have toppled in some places but that's about all.

retsibsi• 5 years ago

There are some towns nearby. Worst I've heard of so far is broken windows, cracked ceilings and the like. Definitely some potential for injury, but I haven't heard of anyone significantly hurt.

anotherevan2• 5 years ago

The epicentres were close to Mansfield[1] which is a town of about 4,800. According to State Emergency Services (SES) reports in the news, they've had a bit over 100 requests for assistance, largely related to minor structural damage to chimneys and facades of buildings.

If you search twitter for "Chapel Street" you can probably find some footage of a wall collapse.

Nothing too serious all in all as far as I can tell. No reports of injuries that I've heard.

While there are plenty of small tremors in Australia that usually go unnoticed, ones that are widely noticeable let-alone alarming are quite rare.

[1] https://en.wikipedia.org/wiki/Mansfield,_Victoria

arawde• 5 years ago

Event page on USGS https://earthquake.usgs.gov/earthquakes/eventpage/us7000fd9v...

JanisL3• 5 years ago

I think there's some important context here for people reading this from overseas, geologically Australia is extremely stable as its far from any tectonic plate borders and there's very few large earthquakes here. This quake is one of the largest to happen here. Many people here have never experienced the sort of whole building shaking type of experience we just had.

davidjohnstone• 5 years ago

According to Wikipedia's list[1], it's the strongest earthquake Australia has had since 1997, and that one was in a remote part of Western Australia.

"A Seismologist tells @abcmelbourne it’s the biggest earthquake Victoria has experienced since European settlement" [2]

1. https://en.wikipedia.org/wiki/List_of_earthquakes_in_Austral... 2. https://twitter.com/bridgerollo/status/1440467927140999174

rd07• 5 years ago

Well, that's new knowledge for me. Especially knowing that in its northern neighbor, Indonesia, there is an earthquake somewhere in its region.

JanisL3• 5 years ago

Have a look at some maps of plate tectonics. The huge Australian plate collides with the Sunda plate along a boundary which is much closer to Indonesian landmasses compared to the Australian ones.

Khaine3• 5 years ago

Also discussed here https://news.ycombinator.com/item?id=28611456

Khaine3• 5 years ago

The Australian plate is the fastest moving continental land mass on Earth and is colliding into the Pacific plate to Australia's north and east, and the Eurasian Plate to the northwest. This generates mainly compressive stress in the interior of the Australian continent, which is slowly building up across the plate as it moves northeast about 7 cm per year. Australia's earthquakes are caused by the sudden release of this stress when rocks deep underground break and move along a fault line. 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.

On average 100 earthquakes of magnitude 3 or more are recorded in Australia each year. Earthquakes above magnitude 5.0, such as the destructive 1989 Newcastle earthquake, occur on average every one-to-two years. About every ten years Australia experiences a potentially damaging earthquake of magnitude 6.0 or more such as the magnitude 6.5 Meckering earthquake in October 1968.

hilbert422• 5 years ago

With those facts, I'm surprised that we don't have larger quakes. I remember the Newcastle one, my parents' home had its roof damaged in it. I also recall a rather strong one in the Blue Mountains when I was a kid but can't remember exactly when it was (sometime in the early to mid 1960s if I recall correctly). I think is was on a Saturday in the AM, and I definitely do recall having difficulty walking across my bedroom whilst it was occurring.

CommieBobDole• 5 years ago

Maybe the 1961 NSW earthquake? Though that one was on a Monday morning.

https://en.wikipedia.org/wiki/1961_New_South_Wales_earthquak...

Wikipedia has a whole list of significant Australian earthquakes, if that's not it.

https://en.wikipedia.org/wiki/List_of_earthquakes_in_Austral...

user123456780• 5 years ago

I don't know why but I really thought Australia was the most stable continent in the world (I guess thanks Education Queensland).

I have lived here my whole life and never experienced an Earthquake.

simondotau• 5 years ago

Your education didn't fail you. Australia is an incredibly stable land mass because it sits in the centre of a single plate.

senectus12• 5 years ago

its is... very very stable.

those are facts but they're not really in context.

thisrod• 5 years ago

Australia is really stable. The edges of the Australian plate are in New Zealand and Java, which aren't. But tectonic plates are big, and we're in the middle.

baggy_trough• 5 years ago

Strange it's so flat then.

dustintrex• 5 years ago

With all due respect, you're making that sound a lot worse than it is when compared to places that are genuinely earthquake-prone. Australia is extraordinarily stable in geological terms and well outside the Pacific Ring of Fire, which frequently generates earthquakes of magnitude 9+. And since the magnitude scale is logarithmic, M9 is 1000x more powerful than M6.

Yes, magnitude does not equal seismic intensity and all that, but Australia has never in recorded history experienced a M7+ earthquake, while Japan alone experiences one every couple of years and New Zealand has had 4 in the last 5 years.

bhrgunatha• 5 years ago

M9 is 1000x more powerful than M6

I assume you're using moment magnitude [1] since it's the most common measure. In fact every 2 integers is a 1000 times increase [2] so M8 is 1000 times more powerful than M6.

[1] https://en.wikipedia.org/wiki/Moment_magnitude

[2] https://en.wikipedia.org/wiki/Moment_magnitude#Definition

Khaine3• 5 years ago

I never claimed Australia has it bad. I took this from Geoscience Australia's website on why Australia actually gets earthquakes.

gHosts2• 5 years ago

Feels like some more detail is needed somewhere... sounds sort like "The Australian Dollar is the fastest moving currency"...

...that might be so, but moving relative to what?

megablast• 5 years ago

Than other plates.

jiggawatts3• 5 years ago

A "fun" side effect of this rapid movement rate is that Australia drifts noticeably relative to GPS-based coordinates. Many programmers made the lazy assumption that coordinates remain fixed and don't need to be adjusted based on the current date.

The effect of this is that the maps in my car are already out by several meters. It's sufficiently bad that it'll sometimes jump to a different road.

Geoscience Australia developed the new "Geocentric Datum of Australia 2020" (GDA2020) to fix this, but not a lot of software has been updated with it as of 2021.

See: https://www.ga.gov.au/scientific-topics/positioning-navigati...

chrismorgan6• 5 years ago

Several metres is a slight exaggeration, not enough to matter for such purposes anyway, and may even already be taken into account.

From 1994 to 2020, the physical difference was about 1.8m (that’s comparing it with another map projection, but what else can you do?), so in what should be the worst case scenario (if they were actually using accurate maps which I think would reasonably imply nothing worse than GDA94), you should have less than two metres of drift, and the only time that’s ever going to matter is when you want to identify service roads distinctly from the adjacent main road. And continental drift is probably still even within your car’s GPS sensor’s margin of error. No, I don’t think you can reasonably blame continental drift for road jumping; it’s typically going to be bad map data, with roads simply being marked in the wrong place. I have a 2010 Mazda 3 with maps from 2010, and out in the country its maps are commonly out by 10–20 metres, with the largest deviation I’ve observed where I know the route hasn’t changed in at least the last couple of decades being about 150m.

To my mind, the real doozy about these geodetic datums is that they’re time-dependent, including a prediction of continental drift. I have no idea whether the car’s maps system does do that, but it should be doing something like storing all coordinates in GDA94, rendering in MGA94, and projecting GPS coordinates into that coordinate space, so that continental drift’s effects are negligible.

(I’ve wondered casually about continental drift in map projections before, but never gotten round to investigating the reality of it. I didn’t realise they could be time-dependent until today. I must get round to asking my dad about it, as he’s done quite a lot of maps and projections stuff.)

57844743385• 5 years ago

This doesn’t have anything to do with earthquakes.

GPS doesn’t have anywhere near the precision you think.

gmurphy• 5 years ago

Like most of the earthquakes I felt in the bay area, I spent most of it thinking it was an unbalanced dryer in the final stages of its cycle.

It roughly felt equivalent to the 2014 Napa Quake (which was also a 6). For normally geologically-quiet Melbourne, however, this would be the strongest quake ever recorded.

NoPicklez2• 5 years ago

We will rebuild Picks up fallen picnic chair

getmoheb• 5 years ago

first hand report from 600km away: my windows rattled, briefly, and i swayed ever so slightly on my chair.

cheesecake_luvr• 5 years ago

From Brisbane: my right eyebrow was raised when I heard about it.

Johnythree• 5 years ago

Traralgon here: Started as a rumbling, then changed to low frequency shaking. Was quite scary.

No damage here, but lot of junk fell over in the kitchen.

chrismorgan6• 5 years ago

I grew up with an anecdote along the lines of that in the 60s or 70s there’d been one of the biggest earthquakes ever recorded in Australia, and the total property damage had been that one cow shed fell over, because that’s how empty much of Western Australia or Northern Territory is. The anecdote may be slightly exaggerated for comedic effect, but it’s also probably not far off the truth.

vmception• 5 years ago

5.9

peanut_worm• 5 years ago

Huh I didn’t think Australia had earthquakes

senectus12• 5 years ago

not very often no.

we're geologically very stable. (but also as a whole continent moving quite a lot)

shirro2• 5 years ago

We don't get big ones with high frequency as we are not on a tectonic boundary. No active volcanoes either.

There are faults and stresses within the continental plate but they mainly produce smaller earthquakes with lower frequency but they do happen. Given the population density people rarely feel them. So even a moderate quake is a huge novelty. I can understand why people are so excited and sharing it on social media. I am probably about 700km away and I only barely felt it and it might be the only earthquake I feel in my entire life.

notriskfree• 5 years ago

Macron stamps his feet and this happens. You better watch out down there.

robertwt72• 5 years ago

I was cooking pancake before my stand up meeting, then the floor was just shuffling at the apartment. Everyone ran off outside the building. It was pretty frightening for first time feeling, apparently the affected areas spread out so far from west to eastern suburbs.

inopinatus• 5 years ago

This feels like half the story; for closure I hope you can inform us how the pancake turned out.

robertwt72• 5 years ago

I turned off the stove before I went out. However the pancake stuck on the pan, and I continue with my standup...

jp0d5• 5 years ago

I work for a Kiwi company and many of my colleagues are Kiwis. When I posted this on company messaging platform, many of them were surprised that Australia gets earthquakes too. I felt quite strong tremors here in Ringwood, Vic. Wife and I ran out through the backdoor to the garden. It was quite an experience.

blobby_barton• 5 years ago

I'm just down the road in Croydon and it was much the same. Thought the retaining wall outside had busted open and I was about to lose my house, didn't even occur to me it might be an earthquake

jp0d5• 5 years ago

I thought it was some possums mucking around on the roof. My wife thought I'd started exercising on the wooden floorboards! Hope you and your family are safe.

anotherevan2• 5 years ago

Yes, I'm in the outer south-eastern suburbs of Melbourne and everyone in our household were standing in doorways. This is certainly the largest and longest one I've experienced, and I've lived in Papua New Guinea and Tokyo for short-ish periods of time.

many of them were surprised that Australia gets earthquakes too.

While we do, ones that are widely noticeable let-alone alarming are quite rare.

jp0d5• 5 years ago

Yes, it's rare! But it's 2021! We've seen many rare things happen! hahaha. Hope you're safe, mate.

nyokodo• 5 years ago

Wife and I ran out through the backdoor to the garden

For future reference, during an earthquake if you’re inside it’s usually far safer to climb under a desk or table, stand in a doorway or up against a wall in the center of your house rather than going outside. Falling trees, power lines, broken gas mains, and even soil liquefaction can be very dangerous.

boznz• 5 years ago

I live 2M above sea level and 100M from the pacific ocean in New Zealand, the last two biggies I was out of my home and 10KM down the road before the aftershocks finished.. Tsunamis can also be pretty dangerous :-)

throwaway0a5e3• 5 years ago

[flagged]

jp0d5• 5 years ago

Thanks for that and you're right. I read that on the SEC website. But, my garden has a good amount of space and has small trees. Far from powerlines. Whereas the house is probably 50 to 60 year old wooden structure built on a sloped block, which trembled quite badly! hahaha. so decided to run with the wifey!

https://www.ses.vic.gov.au/plan-and-stay-safe/emergencies/ea...

pseudosavant• 5 years ago

I was on Zoom with some Australian coworkers when this happened. Cameras suddenly go off, and when they turn it back on they were kind of speechless.

It was kind of funny for a Californian. Although the strongest earthquake I've ever experienced was in Indiana. Go figure.

macintux• 5 years ago

Although the strongest earthquake I've ever experienced was in Indiana.

That is…unexpected. I’ve felt two here in Indiana in 50 years, neither of which were all that notable other than the fact that we almost never get them.

(Knock on wood)

AHappyCamper3• 5 years ago

Melbournians who left their homes for fear of the roof collapsing were jailed for breaking quarantine. Premier Daniel Andrews stated: "Trying to survive a natural disaster is no reason to spread COVID. You will all be punished." (note: this comment is satire)

bobby_bob• 5 years ago

This is poor satire.

"In an emergency" has always been allowed reason to leave home during the Victorian lockdowns.

1 - https://www.coronavirus.vic.gov.au/how-we-live

AHappyCamper3• 5 years ago

Pieces of roof falling on your head from a 5.9 Richter Scale earthquake is not "an emergency". It is actually a sign of White Privilege, since only White People are rich enough to have places with roofs.

More importantly, I am worried your comment has breached the Victorian Standards of Acceptable Speech (VSAS). "This is poor satire" - expressing your own opinions is strictly forbidden and is punishable by years in hard labour camps or by firing squad. Though this sounds extreme, it's really for the safety of the people, to protect them from dangerous thoughts. Please be careful about what things you share online.

(note: this comment is satire)

kimburgess• 5 years ago

View of the earthquake, as seen by one of the city's fiber optic networks: https://twitter.com/_______kim/status/1440661525933412361.

yalogin• 5 years ago

This is the earthquake for which the anti vax nuts were saying the government created the earthquake to quell the riots.

Earthquake in Melbourne, Australia (9.15 AM 22nd Sep 21, AEST)

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