Originally published at: Australia earthquake shakes TV studio | Boing Boing
…
6 Likes
Having lived through this this morning, their reaction was pretty typical for folks across the city. It wasn’t especially dramatic (55 reports of minor damage to buildings; no reported injuries), but it doesn’t happen very often so we’re not used to it.
15 Likes
Yeah, I’ve learned quite a bit about mid-plate tectonics in the last 8 hours!
12 Likes
There’s a mid-plate fault in the middle of the states called the “New Madrid” fault (pronounced MAD-rid). Ocasionally it wakes up and gives a jolt that reminds people it is there. 200 years ago it was the source of two of the most powerful earthquakes in the country. One day it will destroy St. Louis.
12 Likes
9 Likes
We get the occasional rumble here in the U.K., which is remarkable if you look at the second map above. They’re very slight, usually around a 3 or so, I experienced one myself late one night, there was a deep rumbling, and some glasses and other items on a sheft rattled briefly, a bit like a heavy truck driving past.
I think the epicentre of that one was up in the Midlands, I live in the south-west of England, not far from Bath at the very bottom of the Cotswolds. Not generally recognised as tectonically unstable… 
Well, every day’s a school day! I’ve just done bit of research, and the U.K. gets a lot more than I’d thought.
9 Likes
Woke me up, I thought it was the washing machine.
10 Likes
12 Likes
I was woken up by the '08 Lincolnshire quake. I was 50 or 60 miles away and in my sleepy confusion thought the upstairs neighbours were moving furniture
3 Likes
9 Likes
It’s due to compression of the Indo-Australian plate by the spreading ridge in the South Indian and Antarctic oceans. Australia buckles as the ocean floor expands and releases the pressure as thrust faulting.
Australia is mostly a tectonic quiet zone, but there are some oddities like an active chain of volcanoes running along the Eastern side of the continent, none of which have erupted since European settlement.
3 Likes
The UK is very heavily faulted from the Caledonian and Variscan orogenies as well from rifting of the North Atlantic which originally began under the West Midlands and then the North Sea before deciding that a break with America was needed. The direct causes of the 'quakes isn’t entirely clear, but we’re not immune to the compressive effects driving the growth of the Alps and there is probably some link to isostatic rebound caused by the melting of the Pleistocene ice sheets
3 Likes
Earthquake or a structural thing? YES!
1 Like
Yeah, living in CA, being somewhat “used” to earthquakes, our building codes, insurance requirements, etc… have built in a lot of protection against the worst that most earthquakes will do.
It’s also the common “joke” i get asked the most when visiting out of state: “Oh you’re from CA, how do you live with the earthquakes?” And I say, “I sleep pretty well.”
Better than a flood, tornado, or hurricane zone.
So, yeah, because that whole part of the country is built of out bricks when they’re hit when a big one it’s gonna be pretty, pretty, pretty, bad.
The New Madrid quake is completely fascinating and a crazy read. If that happened today, a lot more the St. Louis would be destroyed.
2 Likes
“… and was at a depth of 10 kilometres.”
3 Likes
“…and was at a depth of 10 metres”
That seems really shallow.
Edit: It seems that @catsidhe shared my confusion and did some research.
I’d treat that 10km figure with caution. Currently, the calculated depth figures for the focus of this 'quake range between 2km and 12km, but there is a lot of uncertainty.
10km is a so-called ‘fixed depth’ which is a fairly typical depth for continental earthquakes; it is assigned to earthquakes when there is not enough data to assign an accurate focus. More data processing might allow a more accurate focal depth to be calculated.
5 Likes
While I take your point, it’s clear that “10 metres” is just wrong, and the most likely explanation is that “10km” got turned into “10m” somewhere in the quoting chain.
That’s not even taking into account “the depth was, according to current data, 7km±5km, taking into account basalt layers and sedimentary depo— ‘ten kilometers’. Just write down, ‘it was ten kilometers deep’. Anyone who needs to know in more detail knows how to find out.”
4 Likes
