My post of 02/04/2004 04:57 AM identified a NASA article about "mobile charges" and related issues. A
question about "mobile charges" was brought up on another forum.
The ELFRAD technical forum (
http://www.elfrad.org/ ) had identified unusually large "in-earth" pulses
that had opened fuses on an earth antenna protection circuit. There were a number of questions
concerning the source of the "pulse" and I mentioned that a "mobile charge" identified in the NASA
report could appear as a pulse to the receiver. Unknown to me, the author of the NASA report was a
"quiet" member of this forum, Friedemann Freund. The following is the discourse concerning the "pulses".
Quote:
Some comments on the pulse that opened 250 mil fuses.
It has to be local to the site to pop the fuses, but the actual intensity, origin and
bounds of the pulse are unknown.
The following site discusses a NASA report on "mobile" charge clusters
moving through the earth.
http//earthobservatory.nasa.gov/Newsroom/NasaNews/2001/200112076296.html
A quote from the article, '"These charges are not easy to pin down. They move with
impressive speed, as fast as 300 meters (1,000 ft.) per second," he said.'
The article did not state how the "charges" were detected, but a fast moving charge
cluster could appear as a pulse to a detector in its path. The pulse could have a
different origin than what is being described in the NASA article. There are some complex
processes going on in the subsurface that we do not fully understand.
FrankM
|
The reply on the forum from Friedman Freund is as follows:
Quote:
I'm responding to your message sent to the Elfrad group (of which I am
a happy, though mostly silent member). I want to clarify two things
that were mentioned in this 2001 piece with reference to my work
(1) the "impressive speed" of the positive hole charge carriers and
(2) how the speed was measured.
(1) Since 2001 we have done a lot of additional work along these lines
and seem to understand now that the "speed" is the speed with which the
signal travels, i.e. the speed with which a charge pulse travels. It is
NOT the drift velocity due to the physical displacement of the charge
carriers.
(2) The measurements were done during impact experiments where we shot
a projectile at rock cylinders or rectangular blocks of rock and
measured the time it took after the impact for the positive charge
cloud (several hundred mV) to reach a series of capacitive sensors.
When we used quartz-bearing rocks like granite we, the piezo-electric
response enabled us to "see" the passage of the P and S waves
(compressional and translational), which travel at close to 6 km/sec
and 3.4 km/sec, respectively. The propagation of the positive hole
charge signal was much slower.
I should note that I'll have the opportunity to repeat the impact
experiments in the near future and hope to thus learn more about the
elusive positive hole charge carriers in rocks.
I should also mention that I followed with great interest the damaging
EM "pulses of unknown origin", which Charlie reported. It's fascinating
and puzzling.
Friedemann Freund
|
What should be noted is that electron drift, the conventional process for conduction, is different from the
"charge" propagation noted in the NASA report. Note the statements,
"The propagation of the positive
hole charge signal was much slower." and
"the elusive positive hole charge carriers in rocks".
One of my earlier questions was ,"how much do these extra free electrons contribute to earth conductivity
in the upper crustal area?". Now I can add, "How much do the positive hole charge carriers contribute
t
