New Madrid Quake

[K Frame]

Yellowstone is another critter entirely. Its earth quake activity is caused by a mid-plate volcanic hot spot, not a plate subduction zone (Ring of Fire) or an intraplate fault (New Madrid and Washington, DC, earth quakes).

[Ron]

https://earthquaketrack.com/

Check out your location and see if the end is near 

[MillCreek]

In my part of western Washington, we would have earthquakes and wildfires to worry about.  At 540 feet of elevation I am not worried about a tsunami from Puget Sound.  All of that pales in comparison to living seven miles, as the ICBM flies, from the Jim Creek Naval Radio Station. Jim Creek does very low frequency communication to the submerged missile and attack submarines, so you have to figure that it will be a prime communication, command, and control target if we have any sort of strategic nuclear exchange.

[BobR]

I have always been fascinated by the New Madrid quake. Where I grew up in SW Oklahoma we would have an occasional quake, usually reported and not felt. When I lived in Santa Clara CA I could almost tell you how strong the quake was by how much my dresser drawer pulls rattled. I even felt one in PA one time, no where is safe from those things but most people don't realize that.

bob

[charby]

Another thing that is weird is the Midcontinent Rift and it could have the ever so slight potential to do something interesting.

https://eos.org/features/new-insights-into-north-americas-midcontinent-rift

[charby]

In my part of western Washington, we would have earthquakes and wildfires to worry about.  At 540 feet of elevation I am not worried about a tsunami from Puget Sound.  All of that pales in comparison to living seven miles, as the ICBM flies, from the Jim Creek Naval Radio Station. Jim Creek does very low frequency communication to the submerged missile and attack submarines, so you have to figure that it will be a prime communication, command, and control target if we have any sort of strategic nuclear exchange.

There is another active VLF naval antenna buried in near the middle of Iowa. When it was declassified, it became a talking point as part of the spiel on the Boone Scenic Valley Railroad Excursion.

[230RN]

Very interesting video.

I've been through two "felt" earthquakes, one supposedly due to pumping of water into fault zones at the old Rocky Mountain Arsenal.  First was in Boulder, and I was sitting on the pot and got splashed by my own effluent, ick.  Second was in Denver in a building which had a six or seven story atrium with lamps hanging down from the ceiling to various floor levels.  They swung kind of crazily because of their differing pendulum lengths.  After I observed this, I realized that I had felt something a minute before.

Terry

[K Frame]

In my part of western Washington, we would have earthquakes and wildfires to worry about.  At 540 feet of elevation I am not worried about a tsunami from Puget Sound.  All of that pales in comparison to living seven miles, as the ICBM flies, from the Jim Creek Naval Radio Station. Jim Creek does very low frequency communication to the submerged missile and attack submarines, so you have to figure that it will be a prime communication, command, and control target if we have any sort of strategic nuclear exchange.

Dude, I live within spitting distance of the Pentagon, White House, Capitol, and a gazillion other high priority assets.

In the event that *expletive deleted*it gets real, it's not just going to be my personality that's glowing...

[K Frame]

https://earthquaketrack.com/

Check out your location and see if the end is near 

It's interesting looking at the data on that tracker...

The majority of the quakes listed all happened at a depth of roughly 10 KM, or well within the confines of the crust.

A couple have happened between 18 and 90 KM, also generally with in the crust zone, or not far off it.

Then there's the one that happened at 400 KM. Hello subduction zone earthquake!

[230RN]

Intel is (supposedly) going to build a giant semiconductor fab in Ohio, and one of the reasons was "very low seismic activity".

Well, compared to California...

Re microquakes and Intel, at one point I was operating a delicate vacuum gauge which relied on the slowing down of a spinning ball suspended magnetically in the vacuum.  It was called "the spinning rotor gauge" and was touted by NBS/NIST as a possible new transfer standard for measuring ultra high vacuums.

Seemed like almost every day the damned thing would give crazily impossible results around three o'clock-ish.  It took a while before I realized that this was due to a coal train rumbling by about half a mile from the lab building at about that time-ish every day-ish.  The apparatus would vibrate slightly, while the rotor ball would tend to stay in the same place by some Newtonian law or another, and would therefore yield the crazy readings.

The -ishes explain why it took so long to figure it out.

Oh, those damned intervening variables!

Terry, 230RN

NOTE Many semiconductor MFRing operations are under vacuum.

[K Frame]

So, it wasn't your balls that were jiggling...

Interesting...

[grampster]

We live in SW Michigan.  In my lifetime, we've had 3 or 4 quakes that I have experienced.  All of them were just a feeling you got that was really odd, hard to explain, and then maybe a few rattles of dishes.  Then media would confirm during the next news hour.

[Bogie]

I was thinking that I was getting some nasty tinnitus...
 
Deep bass stuff at times.
 
I'm guessing that my house's poured concrete slab foundation is built fairly close to rock, if not directly on rock.
 
There's a MAJOR freight yard around a mile to a mile and a half north of me.
 
I think I'm hearing the occasional train. Either that, or the Old Ones are tunneling beneath the house.
 
(and STL has a LOT of very large tunnels and some sizable cave systems that have been used for industrial purposes)

[230RN]

So, it wasn't your balls that were jiggling...

Interesting...

Roffle.  Nope, as Newton said, a spinning ball at rest tends to stay at rest.  There were three-plus magnetic operations going on with that gauge.  The field(s) set up to suspend the ball (actually two magnetic interactions there), the field(s) set up to rotate the ball, and the magnetic sensor to sense its RPM slowdown (due to friction with the remaining gas molecules in the vacuum.)

I guess you can make a gauge out of any related effect if you want to get ridiculously complicated about it.

But I guess by now they've got most of the kinks worked out of it ("We can correct that in the software.") because it's now a viable gauging system:

https://www.jlab.org/accel/inj_group/vacuum/SRG-2_manual.pdf

I don't know how they're getting various earthly tremors out of the system... including from trains going by.

[Ben]

You're definitely in an intraplate area. The entirety of Idaho is intraplate.

But, being in an intraplate area does NOT mean that you don't get earthquakes. They just tend to be smaller and a whole lot less destructive.

Yes, generally we get many smaller quakes. The one I referred to from 2020 was a 6.5, which even back in CA we considered a decent shaker. I can't remember the predominant waveform, but it had a VII intensity, which is pretty severe. I recall there was some moderate damage around the epicenter in the Sun Valley area. Since then, there have been ongoing microquakes at a much higher than normal incidence, so maybe something is slowly shaking loose in these parts.

[RoadKingLarry]

Biggest I've felt in Oklahoma was the 5.8 quake in 2016.
We.get quite a few 4.5 range shakers, including a 4.8 a few.days ago, blamed on fracking but I've never noticed them.
The 5.6 got my attention, it only lasted a few seconds but long enough to begin evacuation of the house.

[charby]

Biggest I've felt in Oklahoma was the 5.8 quake in 2016.
We.get quite a few 4.5 range shakers, including a 4.8 a few.days ago, blamed on fracking but I've never noticed them.
The 5.6 got my attention, it only lasted a few seconds but long enough to begin evacuation of the house.

I was on wilderness trip in the boundary waters and I set up camp on a old lava flow, sometime after midnight I woke up from the ground shaking. When I was heading for home in the vehicle, I heard on the news that there was a minor earthquake in Oklahoma the same night that I felt the shaking.

[Hawkmoon]

The 2011 Washington, DC, metro earthquake was an intraplate event. Did a fair amount of damage, but sure as hell shocked the *expletive deleted*it out of me.

That was the one that damaged George Washington's monument to white supremacy, wasn't it?

[Boomhauer]

During the 2011 Virginia/DC  quake we didn’t feel it being 350 miles away but I was working in the visitor center and gift shop at one of the parks I worked at and a large metal butterfly wall decoration started vibrating for a couple of minutes I immediately thought it was an earthquake and sure enough found out where it was a few mins later.

Then a couple years later we had a nearby earthquake from the next park I was working at and felt and heard it. It only lasted for a few seconds but was a little disturbing because it was mild shaking and I had never felt one anywhere close to it.

[Regolith]

You do live near some giant sleeping volcanos. I'm not sure how far you are from the Three Sisters but I saw an article about about a bulge growing on one of them. Then you have Yellowstone.

He's slightly closer to Yellowstone than the Three Sisters. The Three Sisters aren't much of a threat to anyone not in the immediate area anyway. I'm way closer to them than he is and I'm still not anywhere near the danger zone.

[K Frame]

I was on wilderness trip in the boundary waters and I set up camp on a old lava flow, sometime after midnight I woke up from the ground shaking. When I was heading for home in the vehicle, I heard on the news that there was a minor earthquake in Oklahoma the same night that I felt the shaking.

You sure you didn't just have a double helping of chili for dinner?

[K Frame]

That was the one that damaged George Washington's monument to white supremacy, wasn't it?

Yep, the very one.

I was at the office on the 4th floor when the initial pulse hit. I was pretty sure that a truck or something similar had hit the building. That was the P wave hitting.

Then the S waves hit. I still wasn't sure WTF was going on but a coworker had been through earthquakes before, so she knew.

[K Frame]

"I'm guessing that my house's poured concrete slab foundation is built fairly close to rock, if not directly on rock."

Doesn't even need to be built on or near rock, it could just be that the soil type in your area transmits the vibrations. Clay soils do a much better job at transmitting vibrations than sandy or loamy soils.

You're in the greater St. Louis area, right?

https://www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/missouri/StLouisMO_1982/StLouisMO_1982.pdf


Soil/rock type and age is is one of the reasons why the DC earthquake in 2011 was felt so far and wide (it was felt up into New England and Canada and as far south as Georgia and as far west as Illinois), while far more powerful earthquakes in California aren't felt nearly as widely.

[K Frame]

Another thing that is weird is the Midcontinent Rift and it could have the ever so slight potential to do something interesting.

https://eos.org/features/new-insights-into-north-americas-midcontinent-rift

Wow. I'd not heard anything about the mid continent rift since my geology courses in college in the mid 1980s. Interesting to see how different the research is today from what they used to say.

[Ron]

I think Isle Royale in Lake Superior is a result of the mid continent rift.

Up in da UP, the area I camp, backpack and do winter sports is comprised of some of the worlds oldest exposed rock.