Virginia quake seismic waves march across the US

[davenquinn]

@neilpquinn0 What is that supposed to mean, anyway, sir? I will not have aspersions cast against my professionalism...

[MrTyler515]

is it me or does the flahy colors make u feel like youre on serious drugs!!!!!!!!!

[ecshome]

Simply amazing that we can measure such a minut movement of the earth.

[ecshome]

Simply amazing that we can measure such a minut movement of the earth.

[AlternateLonestar]

That's weird. I didn't feel a thing on the Gulf Coast.

[astrophonix]

Sightly off-topic, but an important skeptic issue. A 'paranormal' group in Colorado are trying to silence criticism of their 'ghost-hunting' scam which has led to them being banned from the Evergreen graveyard which they have desecrated. They are trying now to suppress a video by a false DMCA notice even though they don't have any rights to the content. Please help. Details here: watch?v=2dfkGFz5iFU&feature=fe­edu

[pocoapoco2]

What I don't understand is how such a small amplitude wave isn't lost in noise generated by a host of other sources.

[pocoapoco2]

@pocoapoco2 Never mind. I was thinking nanometers not microns. I had one of those brain air releases. 22µm is almost one thousandth of an inch. It sure is moving pretty speedily. Looks to be about 5-6 miles/second.

[miksulder]

even bigger shock is coming

[lx45803]

@miksulder Oh no! Maybe the next one will make waves 40 microns tall!

[LBTennis]

Im from Virginia and this was my first quake. I was so exicted ha

[kacey72]

so is there a reason why somebody would feel nauseous and off balance right after the earthquake happened? I know of at least two people who have felt sick and just off.

[Erde04]

so many censors in the plains lol

[JasonVladimir]

crazy!

[FlorinGG]

Its a mexican wave!! Don't you people watch football(the real thing)?

[baleydee]

holly shit!

[AnnaTFan]

Oooh sparkley!

[Imamkoolz]

lol i love how where minneapolis is, there isnt a little circle. YAY

[GluttonForSex]

Kill all the scientists, so that this never happens again !

[Steaphany]

Why is it that these sorts of events are reported by meteorologists and astronomers ?

Shouldn't we have "TheBadGeologist" or "Rock Watcher" telling us to "Keep looking down" ?

[MCCustomMapReviews]

Comparing to California, our houses on the east coast are made of toothpicks, so think about others before you think of yourself.

[mikesandytoes]

@MCCustomMapReviews toothpicks? i am a carpenter and i can tell you house's on the east coast, at least the boston area, are built well

[TheAndrewDays]

@MCCustomMapReviews toothpicks? the big bad wolf will huff and puff until he blows your house down though.

[skaterrebel]

Disco.

[TechSynapse]

We will rebuild.

;___;7

[antdude]

Wow, west coast too?

[truvelocity]

Praise, Jesus. God shook up our country to tell us to eat more Lucky Charms.

[eicebleu]

Huh, I guess I should have felt something here in East Texas, but I didn't. Maybe it's because I'm on the second floor?

[OUdarling]

So, this may be a dumb question, but... what's with the weird hole somewhere between Wichita and Coffeyville, Kansas?

[hens0w]

@OUdarling on the original there a ring and then some more data relating to the ringed one and it seems to have become a spur here

[MateoJH]

@OUdarling If you are referring to the Yellow circle, that's just the location where the graph on the bottom is coming from.

[Saukko31]

Simply amazing, thanks for sharing.

[keihinv]

Hard rock = good propagation and clearly defined wave patterns.  Very cool visualization.

[rednecktrucker1969]

We had a quake hours before in NM/CO boarder, no one is mentioning that. :)

[manouky]

We felt it in Montreal, Quebec !!

[thedevil549]

@manouky no u didnt jerkoff, i didt feel it in ct

[endtoNWO]

@thedevil549 I live in Westfield Massachusetts and i felt it.

[MarcJX8P]

Wow, that is amazing. It's interesting to see how the shockwave seems to keep reverberating longer in certain coastal regions than others.

[rneville101]

Cosmic. No, I mean terrestrial.

[LadyMyara]

nice march! JK!

[shaithesm0ck]

why does the activity stay longer in texas?

[graey42]

@shaithesm0ck I'd like to know, too. Anyone?

[iamgoddard]

Awesome!

When it hit us, I ran out of my house, thinking it was going to collapse on me. I'm not sure I was ever so bewildered, never having experienced anything like it, being an east-coaster all my life.

[angelikad34]

This should show all the waves, including the ones in Canada. Its only part of a pic. How can you see the full pic of something like this, leaving part of it out. Its wrong.

[SkepticalAaron]

@angelikad34

Blame Canada for not building and funding their own array.

[thasupremeoverlord]

Get Your Asses Out Of The New Madrid Seismic Zone! That shit looks trifely!!!!!!!

[lennyhipp]

@keiwon13 "Come on now ?? Get real .!"

come on now, get educated

[transistic]

What kind of vibes?

[AnotherPostcard]

Can anyone that knows more than me tell my why there were so many more vibes in Texas and California? Just a thing I noticed. :)

[AnotherPostcard]

@keiwon13 There are fault lines in Virginia you know. Quakes happen, however infrequently, just like anything else.

[toechesse]

Was there a full moon and what planet was aligned with the moon at the moment of the quake?

[transistic]

Good Question toechesse



[shawmutt]

I knew this would happen.

[leaf16nut]

Crazy, I felt it in Northern Ontario...

Hell of a long way to travel, it was subtle, but thats 2 in the last 2 years I've felt here.

[frustratedlogician]

this is great. i'm in the metro boston area, and i felt nothing...but a handful of my friends felt it in this area :/

[guitarboy12]

Dont hate.. but is this because of ELEnin???

[frustratedlogician]

@guitarboy12 NO! WRONG! not hating, just correcting.

[guitarboy12]

@frustratedlogician Alright, Thanks.

[Mathview]

Non-geophysicist takes a look: Back-of the-envelope gives a group velocity of ~350 miles per second for the fast wave. Interesting. Looks like there is a slower wave at 150 mps speed, perhaps. Sustained oscillations during the last 10 seconds suggest standing waves. Which raises the question are these observed seismic waves reflected by something, to make standing wave activity? Or?

[geoffball]

@Mathview Earthquakes generate 2 waves. A higher frequency P (primary) wave which generates motion horizontal to the surface and a lower frequency S (secondary) wave vertical to the ground (this is the rolling one feels during an earthquake). Due to the different frequencies the two waves travel at different speeds and hence disperse as the move away from the epicenter.

[Mathview]

@geoffball Yes, thanks I've heard of the terminology. Video data suggests a fast wave phase velocity roughly ~ 350 mps, and slow wave phase velocity roughly ~150 mps. (strictly speaking group velocity of the wave packet.) Theory of elastic solids gives the wave dispersion relation in terms of the acoustic speed C in the medium. Simple sound waves are non-dispersive in uniform media. Why are there two wave modes? Do our wave speeds agree with theory? Do standing waves cause the activity 10<t<20?

[Mathview]

@Mathview Thanks again for posting this fascinating quake sensor data. Examination of the graphic data display immediately engages the curiosity. Makes us almost wish for another large earthquake. Almost, I said.

[davenquinn]

The density of sensors in the middle is because the array is slowly moving across the country, west to east. We're essentially doing a complete seismic survey over a period of about 20 years using a fifth of the seismometers that would otherwise be required.

[Zuurkool1]

@davenquinn

My english is better than alot of native speakers, but you started your sentence with saying "the density of sensors in the middle is because..." and i am still not sure why that was... can you explain it to me?

[davenquinn]

@Zuurkool1 I am referring to and attempting to explain the fact that in the central U.S., there is a grid of very closely spaced data points even though coverage is sparse for the rest of the country. I could have phrased it better probably.

[Zuurkool1]

@davenquinn

Allright, but why is that? 

[MateoJH]

@Zuurkool1 because of money and resources

[6violet6]

@Zuurkool1

The readings are from seismometers that are in a "Transportable Array". When the quake happened, the devices were in Oklahoma and Texas. I'll bet that the scattered devices are stationery. There are many in Southern California because we study earthquakes there all the time. In another year, the Array will be further east and we would see the dots clustered in a different place.

[snoopsnoop5]

@davenquinn layman's terms? I see your point but the sensors in the middle are responding to the wave sensitively than the other up north for example? because I saw that the other sensors stopped responding with high density while the down middle ones are still active. thx in advance.

[davenquinn]

@snoopsnoop5 So lemme see - you're asking about the sensors in the gulf coast area, why they're oscillating like crazy while the ones northward die down. It's all about the local geology where the sensors are: The reason this earthquake produces such clear waves is that the geology in VA is dominated by hard rocks like granite. Gulf Coast geology is dominated by loose sediments from the Mississipi River. Those "muddy up" the signal but shake a lot more in quakes...hence the prolonged randomness.

[hypersapien]

@davenquinn thank you, I was going to ask about this specifically.

[neilpquinn0]

@davenquinn Bad geology, Daven, bad geology.

[fegolem]

That was fantastic! Why do the waves persist along the Gulf Coast for so long?

I didn't know the measurements were so precise within microns. Neat!

[theservman]

I'm surprised at the density of sensors in the middle...

[olcorral]

Is that coast to coast in 10 minutes, right?

[vspqbd]

I felt it.

[shanedk]

I just missed it here. My sister ~10 miles north felt it.

[SaintZ42]

I blame Elenin! Or Cuthulu. I forget which one.

[minazumi]

stupid quake woke me up! and I was having sucha good day off here in DC :P

[AlicethePattern]

Thank you so much for submitting! This is a great way to see exactly what happened, I'll spread this around!

[EvannRachel]

Awesome! This brings out the geology nerd in me. Such fascinating stuff. I made a humorous video about the quake, I'll submit it as a response!

[Cyrathil]

It seemed to be that after the wave passed through, the sensors on the U.S.-Mexico border (I was mainly seeing it in Texas, but it also appeared in California) there was still a large amount of activity. Was that just an aftershock (if so why did it seem less on the Eastern coast), or did the quake in Virginia cause the faults in those areas to go haywire after passing through?

[GuyFromCoby]

This took Al Jazeera off the air for a little bit, I was disappointed.

Also, felt in Toronto.

[sfg911]

clearly..... Virginia did something bad to deserve this. What else could cause earthquakes??

[viva0la0life]

@sfg911 Tectonic Plates...

[astrophonix]

@viva0la0life Tectonic Plaits?

[audiophile71]

@sfg911 Hehe! In the words of Christopher Hitchens, "A fault is not a sin."

[sfg911]

@audiophile71 Great quote! gotta remember that

[TifffyCullen1910]

I live in Virginia. :D

I was in science class when this happened.

[astrophonix]

Amazingly clear seismic wave patterns! Science rocks the world!

[tr0n001]

@astrophonix Russia says it was their HAARP that rocked the Pentagon's underground tunnels.

[dreadpiratedan]

woah.

[aMondia]

Oh wow, that was cool. :O

[SCAREDBANANA]

Cool.