EARTHQUAKES!

[jonesdecaptain of 1,000]

So, where is the strength in EQ shock waves of less than one hertz? How does a frequency of less than one hertz "signal?" earthquakes in distance areas as the map above supposedly shows? It would seem to me that if the supposition is true that frequencies of a percentage of less than one would have to have a big increase in power to effect areas of the distance shown on the map, and I don't see how that is possible!

I guess that I'm have trouble understanding how an EQ frequency of .50 hertz, or a sub hertz frequency, is more powerful than frequencies at 1 or above (one) hertz! Radio frequencies are not applicable here. As I understand it earthquake S and P waves are shock waves. On a seismograph when S and P waves flat line, there are no more waves, so how do weakened "sub hertz" waves trigger earthquakes at the distances claimed in the map above?

Bob

The frequency is different from the amplitude of the wave. The amplitude is the height or magnitude of the wave. Both frequency and amplitude have an effect on the "power" or energy in the wave, and a higher frequency (changing or moving faster) means more energy.

Earthquakes are usually so slow that the frequency doesn't make a big different in the power, so they mostly measure amplitude.

I think what it was saying above is not that lower frequency quakes have more power, but that they carry further through the earth, ie the waves are not dampened as much by stable material as high frequency waves would be.

[buffalo_girlcaptain of 1,000]

The frequency is different from the amplitude of the wave. The amplitude is the height or magnitude of the wave. Both frequency and amplitude have an effect on the "power" or energy in the wave, and a higher frequency (changing or moving faster) means more energy.

Earthquakes are usually so slow that the frequency doesn't make a big different in the power, so they mostly measure amplitude.

I think what it was saying above is not that lower frequency quakes have more power, but that they carry further through the earth, ie the waves are not dampened as much by stable material as high frequency waves would be.

So...is it also the amplitude which enables ELF communication? Do ELF waves also travel through the earth's surface?

http://www.vlf.it/submarine/sbmarine.html

[jonesdecaptain of 1,000]

The frequency is different from the amplitude of the wave. The amplitude is the height or magnitude of the wave. Both frequency and amplitude have an effect on the "power" or energy in the wave, and a higher frequency (changing or moving faster) means more energy.

Earthquakes are usually so slow that the frequency doesn't make a big different in the power, so they mostly measure amplitude.

I think what it was saying above is not that lower frequency quakes have more power, but that they carry further through the earth, ie the waves are not dampened as much by stable material as high frequency waves would be.

So...is it also the amplitude which enables ELF communication? Do ELF waves also travel through the earth's surface?

http://www.vlf.it/submarine/sbmarine.html

ELF is an electro-magnetic signal that behaves partly like a wave and is often described in terms of wave mechanics, but is a different sort of wave than the mechanical motion of an earthquake.

In terms of propagation at low frequencies, that's a good question and I'm not sure. They do seem to be similar concept and may have some underlying principles in common.

EM/Radio signal propagation is an interesting topic, especially for communications. This is one of the more valuable things you learn with HAM radio study and practice, though is one of many topics on the licensing tests. Lower frequencies behave very different from high frequencies. There is a huge difference in antennas and propagation through materials for waves 2 meters long (around 144 Mhz) compared to a 30 hertz wave that is 10,000,000 meters long!

[A Random Phrasecaptain of 1,000]

San Andreas is a threat, but remember - California claims only three of the 20 most powerful earthquakes in the US, and doesn't appear on the list until #13 with the Fort Tejon quake of 1857. Excluding Alaska and Hawaii, the 15 strongest US quakes see 7 being in California, with the others shaking Oregon/Washington coast, Missouri, Montana and South Carolina.

While California is inevitably going to get a big one they are mostly prepared with some decent seismic codes. In terms of disruption I fear a large quake in Missouri most (the New Madrid quakes are responsible for the "heel" that you can see on the US maps today) because I just don't think that St Louis is ready. A quake in California is bad and might shut down one port for awhile. A quake in the Midwest can shut down the Mississippi and/or Missouri rivers for months. Do you realize how much of a disruption that is on commerce? And if a bridge or two fail cutting off East/West travel.... how quickly could they get the trains running again?

It seems like a big one in the Midwest could shut down our country to a large degree.

[minganocaptain of 1,000]

Let's make the Hz thing easier to understand.

I give you a uniCYCLE. (cycle. Get it?) It is a learning unicycle so the wheel only turns in one direction.

I put a red dot on the wheel and when you get on the unicycle the dot is at the top of the wheel.

You start to pedal.

Every time the red top comes back to the top of the wheel that is one cycle. If the red dot hits the top of the wheel exactly every second then that is 1 Hz. If the red dot hits the top of the wheel twice ever second that is 2Hz, and if the dot takes two seconds to make one complete turn that is 0.5Hz. And so on.

There is also the concept of amplitude - a wheel 5 feet in diameter can still go around once per second but the red dot is going to move up and down more than a wheel 1 foot in diameter.

Then consider that all other things being equal, the unicycle will have its forward speed changed depending if it is moving through air, water or jello.

[bobhenstracaptain of 1,000]

The frequency is different from the amplitude of the wave. The amplitude is the height or magnitude of the wave. Both frequency and amplitude have an effect on the "power" or energy in the wave, and a higher frequency (changing or moving faster) means more energy.

Earthquakes are usually so slow that the frequency doesn't make a big different in the power, so they mostly measure amplitude.

I think what it was saying above is not that lower frequency quakes have more power, but that they carry further through the earth, ie the waves are not dampened as much by stable material as high frequency waves would be.

Well. they did say hertz and not amplitude, but amplitude probable does answer the question. The depth of the big EQ would have to be well into the mantel, no such amplitude would be sent through many miles of water----- or jello!

Thanks!

Bob

[DrJonescaptain of 1,000]

Good discussion.
Right, Bob, jonesde and others -- there is a big difference between frequency and amplitude; quite well explained above.

ELF is an electro-magnetic signal that behaves partly like a wave and is often described in terms of wave mechanics, but is a different sort of wave than the mechanical motion of an earthquake.

In terms of propagation at low frequencies, that's a good question and I'm not sure. They do seem to be similar concept and may have some underlying principles in common.

EM/Radio signal propagation is an interesting topic, especially for communications. This is one of the more valuable things you learn with HAM radio study and practice, though is one of many topics on the licensing tests. Lower frequencies behave very different from high frequencies. There is a huge difference in antennas and propagation through materials for waves 2 meters long (around 144 Mhz) compared to a 30 hertz wave that is 10,000,000 meters long!

jonesde
captain of 100

Correct -- ELF is an EM wave. As we learn from ham radio operations, LONGER wavelength (implies LOWER frequency) tends to travel further for the same "strength" - amplitude. ELF has "extremely low frequency" and travels long distances, through the earth, through oceans etc.
20-meter band in ham radio likewise travels longer than 2-m (higher freq, shorter wavelength) at the same amplitude (basically the power of the transmitting ham radio -- 5 watts will have greater amplitude than 1/2 watt).

Sound waves and seismic waves also tend to transmit further through the earth; sub-hertz waves should travel farther than higher-frequency waves, at the same amplitude (the Richter scale provides one common scale for e-quakes).

And yes, one can combine two focused ultra-sound (high-freq) beams at slightly different frequencies, in order to generate "beat frequencies" at much lower frequencies. This "trick of physics" has been discussed as a means to beam energy in such a way as to generate "man-initiated" earthquakes, especially at pre-existing fault zones.

[buffalo_girlcaptain of 1,000]

Dr. Jones, are you familiar with Clifford Carnicom's research on ELF/VLF use combined with aerosol spraying?

He helped me understand what I was observing here in North Dakota throughout the summer of 2002. Below is one article on the use of ELF and the beginning of his own research into phenomena he was observing in New Mexico at that time:

http://www.carnicominstitute.org/articles/elf3.htm

Here is a list of Carnicom's observations beginning at the bottom of the list from 1999. His observations on ELF/VLF start in mid-to-late 2002.

http://www.carnicominstitute.org/html/a ... _date.html

[Stella Solariscaptain of 1,000]

This makes the 3rd earthquake my son has felt while on his mission in Chile.

Region: VALPARAISO, CHILE
Geographic coordinates: 32.692S, 71.448W
Magnitude: 6.5 Mw
Depth: 25 km
Universal Time (UTC): 17 Apr 2012 03:50:14
Time near the Epicenter: 16 Apr 2012 23:50:14

Location with respect to nearby cities:
48 km (30 miles) NNE (25 degrees) of Valparaiso, Chile
116 km (72 miles) NW (321 degrees) of SANTIAGO, Chile

[Stella Solariscaptain of 1,000]

Region: EASTERN NEW GUINEA REG., P.N.G.
Geographic coordinates: 5.482S, 147.101E
Magnitude: 7.0 Mw
Depth: 201 km
Universal Time (UTC): 17 Apr 2012 07:13:50
Time near the Epicenter: 17 Apr 2012 17:13:50

[AGalagaChiasmuscaptain of 100]

When an earthquake goes off (or even if you hit a boulder with a large hammer), various mechanical waves of different frequencies are generated. The earth itself, however acts as a "low pass filter", whereby it dampens the higher frequency stuff and allows the low-frequency stuff pass. The frequency(ies) that pass through are called the "resonant frequency" of the earth. So when an earthquake goes off, after a certain distance from the epicenter is traveled, you will find only these low frequency mechanical waves.

Mythbusters explored this concept when they tried to bust a myth whereby using the mechanical resonant frequency of a bridge could collapse it. High grade steel and concrete (because of the rigidity) allow faster frequencies to pass through (like say in the kilohertz) where the earth's crust is more "loose" and allows the long sub-hertz through.

So in this regard, the point that is that the M8.6 in Indonesia acted like hitting a bell with a hammer, it will only resonate at a certain frequency (resonate frequency). The earth is a giant bell and when two plates smack each other and create mechanical oscillations, the only thing that will travel is the resonant frequency, which I think is somewhere around 0.6 Hertz. This can and will cause catastrophic failure.

read more:

http://en.wikipedia.org/wiki/Resonant_frequency
http://en.wikipedia.org/wiki/Mechanical_resonance

[AGalagaChiasmuscaptain of 100]

On a personal note, when the M5.6 hit Oklahoma, I was standing in my living room and at first felt the high frequency burst, kind of like a vibration or buzzing. It tickled my feet. After that sensation died away, my entire house was left swaying back and forth at around this sub-hertz frequency, which was like standing on a skateboard slowly rolling back and forth. This continued for about a minute, then died away. The chandelier absorbed this energy from the house and it started swinging at the same rate. I filmed it

[Jerry J Fletchercaptain of 100]

Today was particularly active.
http://theextinctionprotocol.wordpress.com/

[DrJonescaptain of 1,000]

Thanks for comments -- very interesting.

Buffalo Girl, thanks for the pointer to Carnicom's site -- I visited it. Some intriguing material and ideas.
Yes, I've before noticed Sec'y of Defense Cohen's remarks confirming the existence of earthquake-generation devices... This leads to the possibility of "undeclared warfare" on a particularly large scale... Last-days stuff for sure!

[DrJonescaptain of 1,000]

17 April KSL news:
http://www.ksl.com/?sid=20036872&nid=148

SALT LAKE CITY — Had that seven magnitude earthquake really hit the Salt Lake Valley Tuesday morning, what would we have experienced?

Keith Koper, who directs the University of Utah Seismograph Stations, said the energy released from a magnitude 7.0 shaker along the Wasatch Fault is analogous to a 20 kiloton atomic bomb - similar to the one dropped over Hiroshima in World War II. But instead of the energy from a single bomb, imagine several.

Koper said that "a magnitude seven quake would be about a factor of 25 times larger than that. It would be equivalent to 25 bomb detonations. It would be enormous."

In our case the weapon is not a bomb but the infamous Wasatch Fault. It's 240 miles long, extending from Malad City, Idaho south to Fayette, Utah.

The Brigham City, Weber, Salt Lake, Provo and Nephi segments of that fault run through the most populated areas of our state.

Enlarge image
"P" waves are sharper, and might actually be audible. "S" waves on the other hand come later in a quake and cause the real damage.

At least 23 magnitude seven quakes have hit these segments over the past 6500 years - an average of a big shakeup every 300 years.

"I don't want to say we're overdue, but based on this paleo-seismic evidence and the geologic evidence from trenching the fault, it would not be unexpected for one to happen soon," Koper said.

Tomorrow, five, fifty, a hundred years from now? The experts don't know but say it will happen.

It might not be just one segment of the fault. Researchers now know a big earthquake on one segment might trigger movement on another.

"It could actually increase the stress of adjacent segments and could lead not really to an aftershock but a big damaging earthquake on one of these adjacent segments," Koper said.

So exactly what is under us?

Let's take the 25-mile-long stretch of the Salt Lake segment of the Wasatch Fault along our east bench. It dips at about 50 degrees, angling to a depth under the center of the valley floor of up to 9 miles. In a big earthquake, the fault plane ruptures. The land mass drops away from the east bench.

If the rupture is deep enough, portions of the valley floor could tilt. That could alter the shoreline of the Great Salt Lake, allowing surges of water to flow eastward, perhaps flooding portions of the Salt Lake International Airport, maybe at about knee length.

Because the city is located on an old prehistoric lake bottom, unconsolidated silts and sands will almost surely amplify the shock waves.

"It will be a very terrifying experience. There's no other way to put it."
–Keith Koper, director of the the University of Utah Seismograph Stations

The first wave is called the "P" wave. As Koper described, "people might hear it. It might be a sharp jolt. You might think something hit the building."

Next comes the "S" waves or shear waves and the enhanced surface or long period waves.

"When the "S" waves and surface waves arrive, everybody's world is going to be turned upside down," Koper said.

With these shock waves, expect severe destruction, landslides in the canyons and something called liquefaction.

In the valley where the water table is high, shaking can mix the water and surface soil together liquefying it until the consistency is almost like mush. Heavy buildings on the surface can sink. Sometimes they even tip over.

Scientists know the Great Basin is slowly stretching westward. In fact, all kinds of land masses around us are moving like pieces of taffy.

Is the Wasatch Fault feeling the stress. If so, when will it break loose?

The quake will happen, Koper said, and with a seven magnitude "it will be a very terrifying experience. There's no other way to put it."

[DrJonescaptain of 1,000]

KSLnews again, 17 Apr 2012

SALT LAKE CITY — Utah could soon be hit with a major earthquake. And all across the state people practiced what to do in such an emergency with the Great Utah ShakeOut.

Roughly 900,000 Utahns participated in a simulated earthquake Tuesday morning - schools, hospitals, military personnel, businesses and families. KSL followed the stories of the the ShakeOut all across the state to show what it would be like for the many people in the state, and how best to prepare.

Click down the left side of the page or on videos up at the top to see what happened around the state, as well as learn more about how to be prepared in the event of a major disaster.

In the meantime, here are some interesting stats about what could happen in a 7.0 magnitude earthquake.

* An estimated 30,000 homes could collapse

* There would likely be billions of dollars in damages across the state.

* 23,000 people could be killed.

* Another 30,000 could be injured.

* Upwards of 100,000 people could be displaced from their homes.

[bobhenstracaptain of 1,000]

Were such an earthquake to happen I suspect we'd see President Monson suggesting "OK folks, lets show them how its done!"

I suspect the fast recovery from EQ damage by we the Mormon people would shock the nation!

Bob

[AGalagaChiasmuscaptain of 100]

KSLnews again, 17 Apr 2012

SALT LAKE CITY — Utah could soon be hit with a major earthquake. And all across the state people practiced what to do in such an emergency with the Great Utah ShakeOut.

Roughly 900,000 Utahns participated in a simulated earthquake Tuesday morning - schools, hospitals, military personnel, businesses and families. KSL followed the stories of the the ShakeOut all across the state to show what it would be like for the many people in the state, and how best to prepare.

Click down the left side of the page or on videos up at the top to see what happened around the state, as well as learn more about how to be prepared in the event of a major disaster.

In the meantime, here are some interesting stats about what could happen in a 7.0 magnitude earthquake.

* An estimated 30,000 homes could collapse

* There would likely be billions of dollars in damages across the state.

* 23,000 people could be killed.

* Another 30,000 could be injured.

* Upwards of 100,000 people could be displaced from their homes.

This is .

These graphics, to me, illustrate the danger here. Because the valley floor was the bottom of Ancient Lake Bonneville, it's mostly fill, like DrJones stated.

Even a 6.0 would cause considerable damage:

Salt Lake valley M6.0:


And Salt Lake valley M7.0:


That orange and red is "unable to stand or walk" level of shaking.

For comparison, here's the M7.0 New Zealand EQ (note the difference in scale, but the substantially larger IX shaking in the SLC map, even at over twice the depth):

[DrJonescaptain of 1,000]

Thanks, Agalaga.

This yesterday:

A 7.0-magnitude quake struck off the northeast of Papua New Guinea on Tuesday, the US Geological Survey said, but there was no tsunami warning issued.
The quake hit at 5:13 pm (0713 GMT) 141 kilometres (88 miles) north of the country's second largest city of Lae and 443 kilometres from the capital Port Moresby at a depth of 201 kilometres, it said.

"A destructive tsunami was not generated based on earthquake and historical tsunami data," the Pacific Tsunami Warning Center said in a statement.
Geoscience Australia measured the quake at 6.8 magnitude and at a depth of 215 kilometres but agreed it was unlikely to generate dangerous waves in the developing Pacific island nation.
"It's pretty deep so it's not a tsunami threat we believe, even though it's slightly offshore," Geoscience Australia seismologist Clive Collins told AFP.
Collins said there had been reports of the quake being felt as far away as Goroko, a highland region about 250 kilometres from the epicentre.
"There would be quite some shaking to the areas close by... because it's about 20 kilometres offshore," Collins said.

"So it's obviously been felt in a wide area around Papua New Guinea, which you would expect from something that big."
Quakes of such magnitude are common in impoverished PNG, which sits on the so-called "Pacific Ring of Fire", a hotspot for seismic activity due to friction between tectonic plates.
"That northern part of Papua New Guinea is subject to quite strong earthquakes reasonably frequently," Collins said, adding that the biggest risk in the mountainous country was generally from landslips caused by tremors.

"There are very steep valleys and if it's been wet you get landslides which generally cause trouble. But I think this being a little bit offshore it may not be such a problem," he said.
"Of course it will be a while before we know that."
A giant tsunami in 1998 killed more than 2,000 people near Aitape, on the country's northwest coast.

[AGalagaChiasmuscaptain of 100]

M5.0 just now off Baja:

http://earthquake.usgs.gov/earthquakes/ ... 009g8f.php

[Reginacaptain of 10]

Does anyone know where there is an active LDS Community with abundant water available, not on a fault line, or in a probable earthquake zone, and not subject to violent weather patterns?

[minganocaptain of 1,000]

Michigan is one of the only states that meets that description. No active LDS communities though.

[jonesdecaptain of 1,000]

Does anyone know where there is an active LDS Community with abundant water available, not on a fault line, or in a probable earthquake zone, and not subject to violent weather patterns?

Joel Skousen's book has some good information about these things, with recommendations:

http://joelskousen.com/strategic.html

There are parts of Utah with minimal earthquake threat (ie outside the main Wasatch fault zone), but the better places that match your description are probably best found in Idaho or far western Montana. Land with surface water and that is livable year-round is tougher and tougher to find these days though, and it is pretty expensive.

If you want good water, minimal earthquakes, inexpensive land, but can tolerate a few tornados (sturdy bermed structures are far better for many reasons anyway, and are great against the high winds and debris of tornados) then there are some great areas in the midwest. If family circumstances were different for me, that's probably where I'd be.

[karen2cruisecaptain of 100]

So, theoretically, how can you just up and move? Are y'all independently wealthy or something? "I mean most "safe" places are far from humanity, so what do you do for a job? I mean if the Lord said gather some stuff and go, we'd go..but I havent gotten that dramatic of a response in my prayers yet. Mostly the promptings are more along the boy scout kind of answer of "be prepared".

[buffalo_girlcaptain of 1,000]

Does anyone know where there is an active LDS Community with abundant water available, not on a fault line, or in a probable earthquake zone, and not subject to violent weather patterns?

Sure! North Dakota. We even have a small temple in Bismarck along with two Wards. There are Wards in Fargo, Minot & Williston. There are Branches in Dickinson, New Town, Rugby, Fort Yates, and Jamestown.

Last winter was the mildest anyone can recall. We have LDS people moving into western North Dakota, including Bismarck, Dickinson, Williston, and Minot from all over the United States.

[jonesdecaptain of 1,000]

So, theoretically, how can you just up and move? Are y'all independently wealthy or something? "I mean most "safe" places are far from humanity, so what do you do for a job? I mean if the Lord said gather some stuff and go, we'd go..but I havent gotten that dramatic of a response in my prayers yet. Mostly the promptings are more along the boy scout kind of answer of "be prepared".

The question was in the context of making a move, but clearly that isn't an option for everyone.

As for being wealthy, you don't have to have lots of money to move to a remote area... you just have to have lots of money to do that and maintain a posh standard of living. If you're really flexible about standard of living and you don't have much money or obligations, there are always ways of working with other people to live just fine in remote areas. I suppose worst-case scenario you could join up with one of the intentional communities (ic.org) that is looking for people to join them in exchange for labor.

But yeah, I suppose like anything in life moving to such an area would require hard work and/or sacrifice, like I suppose any other aspect of preparing "every needful thing" would involve... especially if you're one of us who hasn't been blessed financially to excess.

[karen2cruisecaptain of 100]

The question was in the context of making a move, but clearly that isn't an option for everyone.

As for being wealthy, you don't have to have lots of money to move to a remote area... you just have to have lots of money to do that and maintain a posh standard of living.

We arent talking a "posh standard of living" just a living. Husband hasnt grown up to know about farming and ranching. I spent my summers on a farm and could handle that side. But really..he's not an author or a speaker, we arent independently wealthy, If we sold our home I doubt we could afford a home with "acreage" and we arent about to go into debt again. So we will hav to ride out the coming calamity where we are and help and strengthen those aorund us with what humble means we have.

[A Random Phrasecaptain of 1,000]

Does anyone know where there is an active LDS Community with abundant water available, not on a fault line, or in a probable earthquake zone, and not subject to violent weather patterns?

This area of Arizona has everything but the water in abundance. (If you can get a well to give you water, sometimes it is salty/undrinkable. There is a river nearby but the Apaches downstream lay claim to it. But the White Mountain area might fit the bill - Show Low area.)

[Reginacaptain of 10]

Thank you all for your replies which are most appreciated

[jonesdecaptain of 1,000]

The question was in the context of making a move, but clearly that isn't an option for everyone.

As for being wealthy, you don't have to have lots of money to move to a remote area... you just have to have lots of money to do that and maintain a posh standard of living.

We arent talking a "posh standard of living" just a living. Husband hasnt grown up to know about farming and ranching. I spent my summers on a farm and could handle that side. But really..he's not an author or a speaker, we arent independently wealthy, If we sold our home I doubt we could afford a home with "acreage" and we arent about to go into debt again. So we will hav to ride out the coming calamity where we are and help and strengthen those aorund us with what humble means we have.

On a tight budget I'd recommend the book "Dirt-Cheap Survival Retreat: One Man's Solution" (maybe you've already heard of it):

http://www.amazon.com/gp/product/1581607474/

I think he lives in a dry area, but for really cheap and productive land it's hard to beat the midwest. In many areas you can get good farmland for under $2000 per acre... which isn't enough for water rights for an acre of farmland in Utah!

For a while I had some land in northern MO like this, but it was just too far away from my son who lives with his mother in Utah, and other family and friends in Utah. So, now I'm back here on dry land that was still around $7000 per acre and attempting to eek out some food production with animals (goats for now) and dry-friendly plants (nanking cherries, goji berries, jerusalem artichokes) that I water a bit with grey water.

Anyway, even on a budget there are many options. You might also enjoy Mike Oehler's "The Fifty Dollar and Up Underground House Book":

http://www.amazon.com/gp/product/0442273118

For structures that is my favorite book, and I've now built a few structures with variations on plans from that book.

Honestly most of this stuff requires more work than money, but I've been grateful to have a bit of extra money here and there to save myself a lot of labor.