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An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Cantelever a sheet of glass. Put a bucket on it and trickle water in,An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Some inventor came up with sensor that could save money on helicopterAn earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Cantelever a sheet of glass. Put a bucket on it and trickle water in,
drop by drop. Predict which drop will break the glass. Show your work.
My hope was that since the earthquake dissipated a lot of energy, thenAn earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Cantelever a sheet of glass. Put a bucket on it and trickle water in,
drop by drop. Predict which drop will break the glass. Show your work.
Some reading for you: http://tinyurl.com/ylckk3aAn earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Since rotor failure during normal flight within the operating limitationsAn earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Cantelever a sheet of glass. Put a bucket on it and trickle water in,
drop by drop. Predict which drop will break the glass. Show your work.
Some inventor came up with sensor that could save money on helicopter
rotors. It gave about 3 seconds warning before the rotor failed.
It didn't sell.
Or try dropping sand grains on to a pile...with enough grains the sideOn Sun, 4 Apr 2010 22:27:52 -0700 (PDT), Bret Cahill
Bret_E_Cah...@yahoo.com> wrote:
An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Cantelever a sheet of glass. Put a bucket on it and trickle water in,
drop by drop. Predict which drop will break the glass. Show your work.
John
The stressed rocks are 10's of kM deep and spread over an area of 1000 ofAn earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Some reading for you: http://tinyurl.com/ylckk3a
If they could work in something like a piezo effect it would have more
credibility.
Bret Cahill
If they could work in something like a piezo effect it would have moreAn earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Some reading for you: http://tinyurl.com/ylckk3a
The real problem may be that even shallow earthquakes are just deepAn earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Cantelever a sheet of glass. Put a bucket on it and trickle water in,
drop by drop. Predict which drop will break the glass. Show your work.
John
Or try dropping sand grains on to a pile...with enough grains the side
becomes unstable and there is a mini-avalanche. Predict the size and
time of the avalanche.... (I think the answer is one of these fractal
things... or goes as 1/f...)
An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Good analogy, but a little off. You know the displacement but not the"Bret Cahill" <BretCahill@peoplepc.com> wrote in message
news:0a971335-8a95-442d-bdc4-8e62c19ca02b@q23g2000yqd.googlegroups.com...
An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Some reading for you: http://tinyurl.com/ylckk3a
If they could work in something like a piezo effect it would have more
credibility.
Bret Cahill
The stressed rocks are 10's of kM deep and spread over an area of 1000 of
sq. kM. Any measurable piece of that rock like that down a bore hole has
very little strain across it. Remember, in 50 kM of rock the strain may be 3
meters. While a tremendous amount of energy is stored, the amount in any
measurable piece rock is nearly nothing.
The piezo effect is very difficult to measure as a DC charge because of the
very small strain in a small sample and the difficulty in determining what
the zero charge is. If the forces were in motion an AC signal could be
measured but then it's too late.
A laser beam across a fault line can measure the strain or displacement. Of
course the beam can only measure the change over the time it was in place.
There is no known way to determine zero. Also GPS can measure displacements
and determine the change in strain.
Even when you know the collective strain it doesn't tell you anything about
a pending quake. You're looking at a bent spring but an earth quake only
occurs when the rocks holding the spring in position break loose.
Determining when it is about to break has proven to be impossible, to date.
On Tue, 6 Apr 2010 11:25:55 -0700, "Bob Eld" <nsmontassoc@yahoo.com
wrote:
"Bret Cahill" <BretCahill@peoplepc.com> wrote in message
news:0a971335-8a95-442d-bdc4-8e62c19ca02b@q23g2000yqd.googlegroups.com...
An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you
need
to switch to another field.
Bret Cahill
Some reading for you: http://tinyurl.com/ylckk3a
If they could work in something like a piezo effect it would have more
credibility.
Bret Cahill
The stressed rocks are 10's of kM deep and spread over an area of 1000 of
sq. kM. Any measurable piece of that rock like that down a bore hole has
very little strain across it. Remember, in 50 kM of rock the strain may
be 3
meters. While a tremendous amount of energy is stored, the amount in any
measurable piece rock is nearly nothing.
The piezo effect is very difficult to measure as a DC charge because of
the
very small strain in a small sample and the difficulty in determining
what
the zero charge is. If the forces were in motion an AC signal could be
measured but then it's too late.
A laser beam across a fault line can measure the strain or displacement.
Of
course the beam can only measure the change over the time it was in
place.
There is no known way to determine zero. Also GPS can measure
displacements
and determine the change in strain.
Even when you know the collective strain it doesn't tell you anything
about
a pending quake. You're looking at a bent spring but an earth quake only
occurs when the rocks holding the spring in position break loose.
Determining when it is about to break has proven to be impossible, to
date.
Good analogy, but a little off. You know the displacement but not the
strength of the spring OR it's spring constant. Just knowing the
displacement
you don't know either when it's going to break OR the amount of energy
stored.
Obviously it would need to be from well to well, not just one well.An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
Some reading for you:http://tinyurl.com/ylckk3a
If they could work in something like a piezo effect it would have more
credibility.
Bret Cahill
The stressed rocks are 10's of kM deep and spread over an area of 1000 of
sq. kM. Any measurable piece of that rock like that down a bore hole has
very little strain across it.
That might be enough distance to measure _something_.Remember, in 50 kM of rock the strain may be 3
meters.
The problem is everything is going on _below_ where you can placeA laser beam across a fault line can measure the strain or displacement. Of
course the beam can only measure the change over the time it was in place..
It should give actuarials a clue.There is no known way to determine zero. Also GPS can measure displacements
and determine the change in strain.
Even when you know the collective strain it doesn't tell you anything about
a pending quake.
The ultimate yield strength of rocks isn't precise but it isn't aYou're looking at a bent spring but an earth quake only
occurs when the rocks holding the spring in position break loose.
Apparently they aren't going to condemn the neo colonial MexicoDetermining when it is about to break has proven to be impossible, to date.
How is this basic electronics?k...@att.bizzzzzzzzzzzz> wrote in message
news:mudnr5t7627tntcbji5331ah46qg5ujdir@4ax.com...
On Tue, 6 Apr 2010 11:25:55 -0700, "Bob Eld" <nsmontas...@yahoo.com
wrote:
"Bret Cahill" <BretCah...@peoplepc.com> wrote in message
news:0a971335-8a95-442d-bdc4-8e62c19ca02b@q23g2000yqd.googlegroups.com....
An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you
need
to switch to another field.
Bret Cahill
Some reading for you:http://tinyurl.com/ylckk3a
If they could work in something like a piezo effect it would have more
credibility.
Bret Cahill
The stressed rocks are 10's of kM deep and spread over an area of 1000 of
sq. kM. Any measurable piece of that rock like that down a bore hole has
very little strain across it. Remember, in 50 kM of rock the strain may
be 3
meters. While a tremendous amount of energy is stored, the amount in any
measurable piece rock is nearly nothing.
The piezo effect is very difficult to measure as a DC charge because of
the
very small strain in a small sample and the difficulty in determining
what
the zero charge is. If the forces were in motion an AC signal could be
measured but then it's too late.
A laser beam across a fault line can measure the strain or displacement.
Of
course the beam can only measure the change over the time it was in
place.
There is no known way to determine zero. Also GPS can measure
displacements
and determine the change in strain.
Even when you know the collective strain it doesn't tell you anything
about
a pending quake. You're looking at a bent spring but an earth quake only
occurs when the rocks holding the spring in position break loose.
Determining when it is about to break has proven to be impossible, to
date.
Good analogy, but a little off. You know the displacement but not the
strength of the spring OR it's spring constant. Just knowing the
displacement
you don't know either when it's going to break OR the amount of energy
stored.
All true but you can make some educated guesses. The spring constant can be
roughly determined by testing rock samples from depth in the region of the
faults. I suspect every rock type anywhere near the San Andreas has been
studied to death. I claim you really don't know the displacement (strain)
because you really don't know where zero is and it's hard to measure at
depth. And you sure as hell don't know what the stress (force/area) is in
the rocks at depth. But, after a major slippage as we just had, near zero
strain can be assumed where the slip occurred at the surface and
displacement measurement taken from there forward in time. And, of course it
is generally known how much the two tectonic plates move with respect to
each other. That's the engine that drives the whole enchilada.
Correct, you don't know where it is going to break if it is to break fresh
rock but most slippage occurs on the various faults where slippage has
occurred countless times in the past. Friction between the fault boundaries
locks the "spring" in position allowing stress to accumulate. While you can
know a lot of things, just when and where it will fail next time is unknown
and unknowable with present technology.
An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you need
to switch to another field.
Bret Cahill
That might be true if the crust was homogenous. I think it's a lot morekrw@att.bizzzzzzzzzzzz> wrote in message
news:mudnr5t7627tntcbji5331ah46qg5ujdir@4ax.com...
On Tue, 6 Apr 2010 11:25:55 -0700, "Bob Eld" <nsmontassoc@yahoo.com
wrote:
"Bret Cahill" <BretCahill@peoplepc.com> wrote in message
news:0a971335-8a95-442d-bdc4-8e62c19ca02b@q23g2000yqd.googlegroups.com...
An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you
need
to switch to another field.
Bret Cahill
Some reading for you: http://tinyurl.com/ylckk3a
If they could work in something like a piezo effect it would have more
credibility.
Bret Cahill
The stressed rocks are 10's of kM deep and spread over an area of 1000 of
sq. kM. Any measurable piece of that rock like that down a bore hole has
very little strain across it. Remember, in 50 kM of rock the strain may
be 3
meters. While a tremendous amount of energy is stored, the amount in any
measurable piece rock is nearly nothing.
The piezo effect is very difficult to measure as a DC charge because of
the
very small strain in a small sample and the difficulty in determining
what
the zero charge is. If the forces were in motion an AC signal could be
measured but then it's too late.
A laser beam across a fault line can measure the strain or displacement.
Of
course the beam can only measure the change over the time it was in
place.
There is no known way to determine zero. Also GPS can measure
displacements
and determine the change in strain.
Even when you know the collective strain it doesn't tell you anything
about
a pending quake. You're looking at a bent spring but an earth quake only
occurs when the rocks holding the spring in position break loose.
Determining when it is about to break has proven to be impossible, to
date.
Good analogy, but a little off. You know the displacement but not the
strength of the spring OR it's spring constant. Just knowing the
displacement
you don't know either when it's going to break OR the amount of energy
stored.
All true but you can make some educated guesses. The spring constant can be
roughly determined by testing rock samples from depth in the region of the
faults. I suspect every rock type anywhere near the San Andreas has been
studied to death.
I don't think that's a good assumption either. The slippage will stop whenI claim you really don't know the displacement (strain)
because you really don't know where zero is and it's hard to measure at
depth. And you sure as hell don't know what the stress (force/area) is in
the rocks at depth. But, after a major slippage as we just had, near zero
strain can be assumed where the slip occurred at the surface and
displacement measurement taken from there forward in time.
That gives a gross rate, I suppose. Subtracting the real from the expectedAnd, of course it
is generally known how much the two tectonic plates move with respect to
each other. That's the engine that drives the whole enchilada.
Agreed. Too many variables, too little known. Given the consequences it'sCorrect, you don't know where it is going to break if it is to break fresh
rock but most slippage occurs on the various faults where slippage has
occurred countless times in the past. Friction between the fault boundaries
locks the "spring" in position allowing stress to accumulate. While you can
know a lot of things, just when and where it will fail next time is unknown
and unknowable with present technology.
How is your post (sans snipping) basic electronics? Don't you read subjectOn 7 Apr, 00:56, "Bob Eld" <nsmontas...@yahoo.com> wrote:
k...@att.bizzzzzzzzzzzz> wrote in message
news:mudnr5t7627tntcbji5331ah46qg5ujdir@4ax.com...
On Tue, 6 Apr 2010 11:25:55 -0700, "Bob Eld" <nsmontas...@yahoo.com
wrote:
"Bret Cahill" <BretCah...@peoplepc.com> wrote in message
news:0a971335-8a95-442d-bdc4-8e62c19ca02b@q23g2000yqd.googlegroups.com...
An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you
need
to switch to another field.
Bret Cahill
Some reading for you:http://tinyurl.com/ylckk3a
If they could work in something like a piezo effect it would have more
credibility.
Bret Cahill
The stressed rocks are 10's of kM deep and spread over an area of 1000 of
sq. kM. Any measurable piece of that rock like that down a bore hole has
very little strain across it. Remember, in 50 kM of rock the strain may
be 3
meters. While a tremendous amount of energy is stored, the amount in any
measurable piece rock is nearly nothing.
The piezo effect is very difficult to measure as a DC charge because of
the
very small strain in a small sample and the difficulty in determining
what
the zero charge is. If the forces were in motion an AC signal could be
measured but then it's too late.
A laser beam across a fault line can measure the strain or displacement.
Of
course the beam can only measure the change over the time it was in
place.
There is no known way to determine zero. Also GPS can measure
displacements
and determine the change in strain.
Even when you know the collective strain it doesn't tell you anything
about
a pending quake. You're looking at a bent spring but an earth quake only
occurs when the rocks holding the spring in position break loose.
Determining when it is about to break has proven to be impossible, to
date.
Good analogy, but a little off. You know the displacement but not the
strength of the spring OR it's spring constant. Just knowing the
displacement
you don't know either when it's going to break OR the amount of energy
stored.
All true but you can make some educated guesses. The spring constant can be
roughly determined by testing rock samples from depth in the region of the
faults. I suspect every rock type anywhere near the San Andreas has been
studied to death. I claim you really don't know the displacement (strain)
because you really don't know where zero is and it's hard to measure at
depth. And you sure as hell don't know what the stress (force/area) is in
the rocks at depth. But, after a major slippage as we just had, near zero
strain can be assumed where the slip occurred at the surface and
displacement measurement taken from there forward in time. And, of course it
is generally known how much the two tectonic plates move with respect to
each other. That's the engine that drives the whole enchilada.
Correct, you don't know where it is going to break if it is to break fresh
rock but most slippage occurs on the various faults where slippage has
occurred countless times in the past. Friction between the fault boundaries
locks the "spring" in position allowing stress to accumulate. While you can
know a lot of things, just when and where it will fail next time is unknown
and unknowable with present technology.
How is this basic electronics?
On Tue, 6 Apr 2010 16:56:31 -0700, "Bob Eld" <nsmontas...@yahoo.com> wrote:
k...@att.bizzzzzzzzzzzz> wrote in message
news:mudnr5t7627tntcbji5331ah46qg5ujdir@4ax.com...
On Tue, 6 Apr 2010 11:25:55 -0700, "Bob Eld" <nsmontas...@yahoo.com
wrote:
"Bret Cahill" <BretCah...@peoplepc.com> wrote in message
news:0a971335-8a95-442d-bdc4-8e62c19ca02b@q23g2000yqd.googlegroups.com...
An earthquake ain't something subtle.
If you are having problems tracking the stresses in the earth you
need
to switch to another field.
Bret Cahill
Some reading for you:http://tinyurl.com/ylckk3a
If they could work in something like a piezo effect it would have more
credibility.
Bret Cahill
The stressed rocks are 10's of kM deep and spread over an area of 1000 of
sq. kM. Any measurable piece of that rock like that down a bore hole has
very little strain across it. Remember, in 50 kM of rock the strain may
be 3
meters. While a tremendous amount of energy is stored, the amount in any
measurable piece rock is nearly nothing.
The piezo effect is very difficult to measure as a DC charge because of
the
very small strain in a small sample and the difficulty in determining
what
the zero charge is. If the forces were in motion an AC signal could be
measured but then it's too late.
A laser beam across a fault line can measure the strain or displacement.
Of
course the beam can only measure the change over the time it was in
place.
There is no known way to determine zero. Also GPS can measure
displacements
and determine the change in strain.
Even when you know the collective strain it doesn't tell you anything
about
a pending quake. You're looking at a bent spring but an earth quake only
occurs when the rocks holding the spring in position break loose.
Determining when it is about to break has proven to be impossible, to
date.
Good analogy, but a little off. You know the displacement but not the
strength of the spring OR it's spring constant. Just knowing the
displacement
you don't know either when it's going to break OR the amount of energy
stored.
All true but you can make some educated guesses. The spring constant can be
roughly determined by testing rock samples from depth in the region of the
faults. I suspect every rock type anywhere near the San Andreas has been
studied to death.
That might be true if the crust was homogenous. I think it's a lot more
difficult than that because of earlier faults.
I claim you really don't know the displacement (strain)
because you really don't know where zero is and it's hard to measure at
depth. And you sure as hell don't know what the stress (force/area) is in
the rocks at depth. But, after a major slippage as we just had, near zero
strain can be assumed where the slip occurred at the surface and
displacement measurement taken from there forward in time.
I don't think that's a good assumption either. The slippage will stop when
the friction becomes greater than the force, i.e. when the fault locks up
again. That doesn't imply zero force.
And, of course it
is generally known how much the two tectonic plates move with respect to
each other. That's the engine that drives the whole enchilada.
That gives a gross rate, I suppose. Subtracting the real from the expected
rate might give some information. It still doesn't give empirical numbers for
the other variables. It's a crap shoot.
Correct, you don't know where it is going to break if it is to break fresh
rock but most slippage occurs on the various faults where slippage has
occurred countless times in the past. Friction between the fault boundaries
locks the "spring" in position allowing stress to accumulate. While you can
know a lot of things, just when and where it will fail next time is unknown
and unknowable with present technology.
Agreed. Too many variables, too little known. Given the consequences it's
still worth studying.