Earth shakes ....

Post by **euclid** » Sat, 17. Feb 18, 15:52

.... here in Swansea ust a few mins ago. I've never encountered anything like that and it was quite a sensation.

https://www.bristolpost.co.uk/news/bris ... nt=sitemap

Cheers Euclid

burger1 · Post by **burger1** » Sat, 17. Feb 18, 16:21

A 4.2 tremor

http://www.bbc.com/news/uk-43097113

clakclak · Post by **clakclak** » Sat, 17. Feb 18, 17:42

Unusual for the UK but I assume the damage was minimal right?

RegisterMe · Post by **RegisterMe** » Sat, 17. Feb 18, 18:46

I've been in a few earthquakes. The biggest was in Istanbul, one of the Izmut quake aftershocks a few years ago. The scariest was, of all places, in Sydney.

red assassin · Post by **red assassin** » Sat, 17. Feb 18, 19:22

clakclak wrote:Unusual for the UK but I assume the damage was minimal right?

We get something of this magnitude every couple of years or so. I haven't heard any reports of any significant damage.

I felt it, though I thought it was a neighbour's washing machine or something until I got a few texts going "did you feel that??".

pjknibbs · Post by **pjknibbs** » Sat, 17. Feb 18, 20:37

The only earthquake I can remember in the UK I never felt, because I was standing up at the time--the people who were sitting down around me all said, "What was that?" while I was standing there wondering what the heck they were talking about!

Hank001 · Post by **Hank001** » Sat, 17. Feb 18, 21:16

Try living at my locale. The center of the largest earthquake on the American continent wasn't in California. It was in the the "boot heel" of the state of Missouri in 1811 and it rang church bells in Boston and New York. Shocks and after shocks lasted 3 days and some were 7's on the new M scale.

My towns right in the "mass damage" area if it lets loose again. Since evidence shows the "New Madrid" fault lets loose every 200 years. We're overdue.
My first quake was here. 5.6 (old Richter scale) in 1966.
To many here since then to innumerate. When in the service got knocked off a stool when a shock wave hit Cold Bay Alaska. Good 8 to 9. Only it wasn't classified an earthquake. A volcano up the Alaskan peninsula let loose bigger than Saint Helens. Not much news about it back in 1983. Nobody lived within a hundred miles of it.

Here the wiki on are local mover and shaker:

https://en.m.wikipedia.org/wiki/New_Madrid_Seismic_Zone

mrbadger · Post by **mrbadger** » Sat, 17. Feb 18, 21:32

They aren't that unusual in the UK, but they're not usually very strong. We had one crack our toilet seat (just after I fitted a new one) and break a load of crockery by knocking it off shelves about 8 years back.

Short lived, and weak, but it did a lot of expensive damage because of the things it broke in the house. No structural damage I think. Although we did find a cracked window pane in some double glazing the following year behind some furniture that had no explanation. That could well have happened during the quake.

Hank001 · Post by **Hank001** » Sat, 17. Feb 18, 21:43

A party from our local "ivory tower" went to the UK to see if the ancient meteor crater that gave Sheffield it's steel cracked deeper layers and caused a deep subterranean fault. Dear departed Mum was a geologist, paleontologist and mining engineer (basic rockhound.) So I knew some in the party. Loved the pubs, saw the sights, did their research and said the data couldn't substantiate nor disprove the contention, but came back with enough shock crystals to assure they all wrote a paper on them.

Antilogic · Post by **Antilogic** » Sat, 17. Feb 18, 22:01

pjknibbs wrote:The only earthquake I can remember in the UK I never felt, because I was standing up at the time--the people who were sitting down around me all said, "What was that?" while I was standing there wondering what the heck they were talking about!

"What...You...You guys are screwing with me, right?"

Rapier · Post by **Rapier** » Sun, 18. Feb 18, 10:35

Antilogic wrote:
pjknibbs wrote:The only earthquake I can remember in the UK I never felt, because I was standing up at the time--the people who were sitting down around me all said, "What was that?" while I was standing there wondering what the heck they were talking about!
"What...You...You guys are screwing with me, right?"

I was in a campervan in New Zealand for a 7 in 2003. I didn't realise there had been a quake until we saw it in the news the next day - I just thought it was a gust front (I'd just got my PhD in meteorology, so everything was caused by the weather!). It's so unusual for most of us that our minds either don't register it or find some other explanation - unless it can;t be denied. In this case, I think the suspension on the van affected how it felt.

Hank001 · Post by **Hank001** » Sun, 18. Feb 18, 11:51

Want long winded explanation of why one person feels a quake when another 5 km away feels nothing? Happens here all the time. There's 40+ known faults in the area and around 2 tremors a month. Rock layers, t and s wave propagation presents or absence of subterranean aquifers (If your on top of one you're apt to rock and roll MORE than on top of an epicenter.) Stand on top of a shallow rock self close to an epicenter you might feel nothing at all as the surface wave bounces off and the slower more powerful wave travels under the shelf. So the best explanation?
Given there are more variables than my pet mice have hairs?
"It depends". How do I know? Come to Southern Illinois and stick around for a while. Seismology becomes a way of life.

mrbadger · Post by **mrbadger** » Sun, 18. Feb 18, 12:15

The ground under you isn't uniform, so it absorbs shockwaves in a non uniform way as well.

That's why one person can feel a strong effect from a quake and another person nearby might not.

Same reason why in my house one rooms contents suffered massive damage because the shelves were able to resonate, causing the contents to bounce off, where other rooms were untouched other than a little rattling.

Morkonan · Post by **Morkonan** » Sun, 18. Feb 18, 13:26

I've lived in several areas with somewhat active fault lines, none too dangerous.

But, I used to also live on a patch of ground that was a perfect shockwave transmitter from a nearby gravel quarry. ("Nearby" in that it was several miles away.) When they set off blasts, my house would shake, sometimes pretty darn heavily. (Stuff would rattle, think it caused some brickwork and mortar splits, etc) And, there was nothing anyone could or would do about it... :/

I've also been shaken awake by both earthquakes and tornadoes. Thankfully, not at the same time. That would... suck.

pjknibbs · Post by **pjknibbs** » Sun, 18. Feb 18, 16:56

mrbadger wrote: That's why one person can feel a strong effect from a quake and another person nearby might not.

I was literally standing next to one of the people who felt that earthquake, so I don't think that was the explanation there.

red assassin · Post by **red assassin** » Sun, 18. Feb 18, 20:50

Yeah, I had the same thing with this one - I was stood up and just felt a gentle tremor which I ascribed to a washing machine; my girlfriend was sat down literally a foot from me and felt it properly.

Hank001 · Post by **Hank001** » Mon, 19. Feb 18, 09:38

Add architectural features to the list then. That's common here that some places in a home are bad places to put up shelves. Great Uncle used to have. A self with two crystal glasses that taped each other at the slightest quake, but you jump up and down on the floor not budge them. A pillar in his basement went right to the bottom of the floor the wall for the self was on. Then again that's when they built basements here. We also have a bad radon problem here.

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Earth shakes ....

Earth shakes ....