Earth - tectonics and geology

[jjohnson]

Sonic booms and thunder can both register on seismometers. Many universities have a department of seismology or instruments of that type that record seismic events. You might try making a few phone calls to local higher ed institutions and see if they can correlate an event on their equipment with the time frame you heard the phenomenon.

About 2 years ago a pair of F-15's were scrambled from Portland Oregon to investigate an intrusion into a temporary "no-fly" zone set up in Seattle for a visit from the President. As usual, they hurried north above mach 1, and laid down a sonic boom carpet almost the entire way. The boom was heard widely throughout Seattle, and numerous phone videos were aired on the evening news, of course. It was mentioned that such disturbances can be picked up on ground-measuring equipment, and were, as this is a seismically dangerous place to live and the U. of Washington and other agencies monitor constantly at many locations. It's be worth asking around about in your area.

Jim

[phyllotaxis]

That was my firs thought too- but in the story linked at the top of the original post, the newspaper contacted the Wilmington office of the national weather service, and they were told there was no registered earthquake at the time of the incidents. The day before, in Virginia, there was a Magnitude 1.8 recorded, but nothing on the day of the event in NC.
In 2010, the news article recording that event specifically mentions the Geological service being contacted and them saying there was no event.
HERE is that article


The mystery remains...

[kell1990]

Do seismographs measure relative motion or absolute motion? I'm pretty sure they measure relative motion. Is it possible that some of the sonic phenomena we hear are caused by major "ripples" in the earth's crust, which could be the source of the types of sounds being reported?

Imagine a long-wavelength wave moving across the water. That is the type of movement that I think might be consistent with both the reported movement on land, yet the lack of registeration on siesmographs.

What could cause such an anomolous movement of the earth's crust? An ourside influence. Which outside influence? The Sun and the cosmos. How? By the manipulation of the earth's magnetic field, which in turn causes the ferric materials in the earth's crust to react, according to flux levels. The earth and everything on it moves simultaneously in this situation.

If this conjecture is right, then there should be corresponding increases in the temperature of the ionosphere and the stratosphere as these waves of EM current move through the earth's space.

[Drethon]

Seismographs have a weighted object on a spring typically, more modern versions may use electronic accelerometers. The measurement occurs when the object on the spring stays relatively still while the rest of the equipment moves around it, or in accelerometers I believe a compression occurs when the "free standing" object inside tries to stay still while everything else moves. The two ways I can think of to prevent movement are a movement slower than the resistance of the material (ex move slowly and the spring will stay with the machine) or gravitational acceleration which affects both the stationary and moving parts.

To produce a booming noise, I don't think either cases are relevant to normally understood situations.

[phyllotaxis]

Well let me be clear- the ground moved.
The windows rattled.
The sound was secondary to the rumble- subtle, but absolutely present.

I can not understand how these instruments *didn't* pick up the events.

It flies in the face of reason, and highlights the bizarre nature of these widely-felt occurrences.

[Drethon]

Us feeling the ground move and seismographs detecting it work on the same principle, namely a suspended object that should stay still when everything moves around it. So if you felt the ground rumble but no seismographs did, it had to either be a very localized movement that did not reach any seismographs or... WTF?

[ElecGeekMom]

Do the sounds start before you notice the movement of the ground/doors/windows? I'm wondering about the timing of the sounds relative to the motion.

[webolife]

My son lives in Virginia and has heard these sounds as well.
I favor an atmospheric disturbance explanation -- similar to the dry lightning hypothesis offered above by Sparky, I wonder if it is possible that downbursts [or "microbursts"] usually associated with thunderstorm or other turbulent activity might be found to occur in relatively clear air conditions as well under the right circumstances... the regionality of these occurrences certainly bears another look at this. Phyllotaxis stated that the ground moved on at least some occasion of the "guns" events... under this view that would have to be a narrowly local occurence.

[seasmith]

Webo,

Given the proximity of the 'Carolina Bays', i wouldn't rule out a telluric conduction

s

[phyllotaxis]

Us feeling the ground move and seismographs detecting it work on the same principle, namely a suspended object that should stay still when everything moves around it. So if you felt the ground rumble but no seismographs did, it had to either be a very localized movement that did not reach any seismographs or... WTF?

Exactly. This is felt for miles and miles- my parents live over 10 miles away to the north of my office and felt it- and Southport is over 10 miles south- these are experienced by a great area. It's just bizarre that these are never apparently recorded by seismographs.

Do the sounds start before you notice the movement of the ground/doors/windows? I'm wondering about the timing of the sounds relative to the motion.

Imagine a huge semi trailer/dumptruck loaded to the hilt with rock passing you at high speed just outside your house at on a poorly paved road. The "sound" you pick up is more the rumble of your building/ground than a distinct audio effect. As I mentioned earlier, we thought it was a semi slamming too hard into the dock area of our warehouse- a rumbling lurch-- but it continued too long-- several seconds, maybe five or six.

I hope this helps describe the perception.

[Drethon]

Imagine a huge semi trailer/dumptruck loaded to the hilt with rock passing you at high speed just outside your house at on a poorly paved road. The "sound" you pick up is more the rumble of your building/ground than a distinct audio effect. As I mentioned earlier, we thought it was a semi slamming too hard into the dock area of our warehouse- a rumbling lurch-- but it continued too long-- several seconds, maybe five or six.

I hope this helps describe the perception.

Subsonic sounds, right on the edge of what you can hear but you can feel it really well....

Human beings can detect sounds in the frequency range 20-20,000 Hertz. If a P wave refracts out of the rock surface into the air, and it has a frequency in the audible range, it will be heard as a rumble. Most earthquake waves have a frequency of less than 20 Hz, so the waves themselves are usually not heard. Most of the rumbling noise heard during an earthquake is the building and its contents moving.

When an earthquake occurs, seismographs near the epicenter are able to record both P and S waves, but those at a greater distance no longer detect the high frequencies of the first S wave

Just throwing out some uneducated thoughts. If earthquakes are typically below 20 Hz, below the level of normal hearing, and you are hearing these sounds just barely it seems like the frequencies are at or above 20Hz. Maybe this rumble is slightly higher frequency than seismometers are designed to detect. A stiff enough spring on a mechanical seismometer would dampen out higher frequencies.

Also a higher frequency sound could indicate an event occurring at or above the surface, preventing the filtering out of higher frequencies that occurs with a below ground earth quake.

Note: Little scientific background supports any of these claims, consider at your own risk

[phyllotaxis]

Sounds reasonable to me on the face of it-- and it does remind me of the quite scientific research on infrasound--

Infrasound is sound that is lower in frequency than 20 Hz (Hertz) or cycles per second, the "normal" limit of human hearing. Hearing becomes gradually less sensitive as frequency decreases, so for humans to perceive infrasound, the sound pressure must be sufficiently high. The ear is the primary organ for sensing infrasound, but at higher levels it is possible to feel infrasound vibrations in various parts of the body.

The study of such sound waves is sometimes referred to as infrasonics, covering sounds beneath 20 Hz down to 0.001 Hz. This frequency range is utilized for monitoring earthquakes, charting rock and petroleum formations below the earth, and also in ballistocardiography and seismocardiography to study the mechanics of the heart. Infrasound is characterized by an ability to cover long distances and get around obstacles with little dissipation.

and here-- look at this:

Infrasound sometimes results naturally from severe weather, surf,[6] lee waves, avalanches, earthquakes, volcanoes, bolides,[7] waterfalls, calving of icebergs, aurorae,lightning and upper-atmospheric lightning.[8] Nonlinear ocean wave interactions in ocean storms produce pervasive infrasound vibrations around 0.2 Hz, known as microbaroms.[9] According to the Infrasonics Program at the NOAA, infrasonic arrays can be used to locate avalanches in the Rocky Mountains, and to detect tornadoes on the high plains several minutes before they touch down.[10]

Infrasound can also be generated by man-made processes such as sonic booms and explosions (both chemical and nuclear), by machinery such as diesel engines and older designs of down tower wind turbines and by specially designed mechanical transducers (industrial vibration tables) and large-scale subwoofer loudspeakers[11] such as rotary woofers. The Comprehensive Nuclear-Test-Ban Treaty Organization Preparatory Commission uses infrasound as one of its monitoring technologies (along with seismic, hydroacoustic, and atmospheric radionuclide monitoring).

Whales, elephants,[12] hippopotamuses,[13] rhinoceros,[14][15] giraffes,[16] okapi,[17] and alligators are known to use infrasound to communicate over distances—up to hundreds of miles in the case of whales. In particular, the Sumatran Rhinoceros has been shown to produce sounds with frequencies as low as 3 Hz which have similarities with the song of the humpback whale.[15] The roar of the tiger contains infrasound of 18 Hz and lower,[18] and the purr of felines is reported to cover a range of 20 to 50 Hz.[19][20][21] It has also been suggested that migrating birds use naturally generated infrasound, from sources such as turbulent airflow over mountain ranges, as a navigational aid.[22] Elephants, in particular, produce infrasound waves that travel through solid ground and are sensed by other herds using their feet, although they may be separated by hundreds of kilometres.

This seems like a good set of candidates for explaining the mechanism--

[TOROID]

I'll go with Kell1990's idea.
It would be interesting to know if these Seneca Guns coincide with solar flares.
The cause has to be above ground to be able to avoid seismic detection.
The fact that the rumble was physically felt just means that the air itself was being made to move around in waves.
This shows the power moving air can have on solid, and not so solid objects.
http://www.youtube.com/watch?v=IyAyd4WnvhU
So it could be the effect of a solar flare slamming into the upper atmosphere, or even the Earth's magnetic field.
Gaps (low intensity areas...the mainstream call them gaps), do occur in the Earth's magnetic field allowing charged solar particles to stream in. The magnetic wave could be transmitted down to the atmosphere magnetically / electrically, almost instantly, and when it reaches the gas of the atmosphere, it ionises and heats the gas causing almost instant expansion and therefore a very high speed pressure wave of extreme low frequency. Possibly creating several waves over the course of several seconds or even minutes as the flares can last a long time, with sharp increases in energy causing more atmospheric pressure waves.

What was that nurse? My medication is ready? Is it that time already?

[phyllotaxis]

Here's another series of strange events popping up---

What Is Causing The Strange Noises In The Sky That Are Being Heard All Over The World?

During the second half of 2011, a lot of people all over the planet started reporting hearing really strange noises coming from the sky. In some instances the noises produced a loud rumbling such as a train, a thunderstorm or the slamming of a heavy door would make. In other instances, the noises sounded more like "groaning". In yet other instances the noises sounded almost as if a trumpet was playing. Dozens of videos went up on YouTube purporting to document this phenomenon, but the truth is that you can fake almost anything on a YouTube video and many dismissed these strange "strange sounds" as an Internet hoax. However, now entire towns in the northern part of the United States are hearing strange noises in the sky and the mainstream media is reporting on it. In fact, one U.S. town is planning to spend thousands of dollars to hire an engineering firm to investigate where these strange sounds are coming from. At this point a lot of theories about these strange noises are being floated, but so far scientists have not been able to give us a definitive explanation for the source of these strange noises. So exactly what in the world is going on?

This phenomenon made national news again this week because of what has been going on in Clintonville, Wisconsin. Hundreds of residents of Clintonville reported hearing incredibly loud noises coming from the sky for several nights in a row. Even CBS News is reporting on what is happening in Clintonville....

Since Sunday, the residents have been disturbed by "booming" noises loud enough to wake them from their sleep.

Last night, hundreds of people attended a public meeting to get to the bottom of booms. But they aren't any closer to the truth.

One resident told CBS News, "The last few days we've been having (a) booming shaking noise."

Another resident said, "(For) a lot of people the house is rattling, you can feel the ground rattling, and it's booming all the time. It's kind of like, what's going on? You don't know what's happening."

So what is causing these noises that are so loud that even the ground is shaking?

According to Fox News, the town has investigated every possible explanation that they can think of for these strange noises....

City officials say they have investigated every possible human cause. They checked water, sewer and gas lines, contacted the military about any exercises in the area, reviewed permits for mining explosives and inspected a dam next to City Hall. They even tested methane levels at the landfill in case the gas was spontaneously exploding.

So far no explanation has been found.So Clintonville has decided to spend $7,000 to hire an engineering firm to investigate the cause of these strange noises.

According to geologists, the town does not sit on any fault lines and the ground beneath the town is very solid. Some geologists are claiming that "micro-quakes" could have been responsible, but others find this explanation to be very unsatisfying.

For many town residents, solving the mystery is not as important as getting these strange noises to stop so that they can get some sleep.

The following comes from the recent Fox News article mentioned above....

"My husband thought it was cool, but I don't think so. This is not a joke," said Jolene Van Beek, who awoke early Sunday to a loud boom that shook her house. "I don't know what it is, but I just want it to stop."

But Clintonville is not the only town in Wisconsin where strange sounds are being reported.

Mysterious noises are also being reported in a town called Montello which is 80 miles away from Clintonville.

Posted below is a local news report that discusses the strange noises that are being reported in Clintonville and Montello....

[kell1990]

The Clintonville event has been ascribed by some media sources to a M 1.8 earthquake that happened in the area. Obviously this happened over a period of several days, so a one-time earthquake isn't the answer here. It also happened over a fairly wide area, sensed by many people. I think the earthquake is a sideshow to the real event.

The earthquake was caused by the same force that caused the Clintonville event, not the other way around.

The way I see this is that the solar system is moving into the ecliptic of the Milky Way galaxy. Forces in this region move at almost a 90 degree angle to normal, almost like an reverse "L" shape, with time on the x axis and force on the y axis, drawn on a Cartesian grid. The closer to the y axis, the stronger the force gets, approximately x^6 or something like that, maybe higher. Almost a vertical slope.

This force, as I imagine it, also envelopes the Sun. The Sun will also exhibit many unusual characteristics, including a dark period when it is in the zone of "verticalitity" (near the y axis), but this will pass after a couple of weeks. As I see it, this is a very sharp increase in external pressure on the Sun, causing its outout to be significantly diminished for a short period.

Many other tectonic movements and other seemingly random geodedic and atmospheric events will occur within this period.


This post may belong in the NIAMI forum, but that's not up to me,