"Phenomenal Variations in the Self-Potential of Rocks"
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April 15, 1985
Catalina Island Monitoring Station
Avalon, Catalina
Copyrighted © by The Townsend Brown family. All rights reserved.
The following report describes a simplified version of a class
of experiments which have been conducted over a period of years. The
findings are of interest for the reason that there is, as yet, no adequate
explanation.
Discussion:
It has been found that certain basaltic and granitic rocks
exhibit a self-potential which undergoes large cyclic variation not related
to temperature, pressure, humidity or other local variables. Long-time
monitoring has revealed periods of the year when the self-potential
correlates consistently with sidereal time, reaching maximum and minimum
values vectoring on the galactic center (17
h43
mRA).
At other times, solar cycles predominate and sidereal component disappears.
Even so, a circadian pattern nearly always exists which cannot be correlated
with ambient laboratory conditions.
Hence, it is of interest not so much that a self-potential
exists but that it varies with a cosmic pattern. It has been found further,
that complete reversals of electrical polarity occasionally take place (See
figure 5, Encl. B) and this suggests that magnetic reversals as with the
tetanohematite lavas may also be present.
The Experiment:
An oval-shaped basaltic rock, approximately 3" x 5" x 8", from the
rim of the ancient Koolau volcano on Oahu, Hawaii, is thoroughly oven-dried
and copper electrodes are painted on opposite sides. The rock is then
covered with an insulating plastic sheath and enclosed in several layers
of aluminum foil, which is grounded. A 5-megohm wire-wound precision
resistor (Shallcross) is attached to provide an electrical load. The load
causes the freely-floating self-potential of the rock to drop from
approximately 300 mV. The rock and resistor are encased in an electrically
shielded, constant temperature box controlled to .1
oC.
BNC shielded cable connects the rock to a double-throw one-hour
timing switch, thence to a strip-chart recorder as shown in the diagram.
When the switch is in position 1 for one minute, the recorder is directly
connected to the rock. When in position #2, for the remaining fifty-nine
minutes, the recorder is connected to a fixed 50 mV constant (battery-fed)
source.
Experience has shown that most recorders have a feed-back
potential which causes them to drift when free. "Clamping" the recorder
to a fixed 50 mV battery during the rest position prevents such drift.
The same result could be achieved by simply shorting the recorder (to zero)
during the rest period, but with ordinary strip-chart recorders the margins
are so tight that problems occur with the ranging scales when the pen is
required each time to return to zero. Hence, the indicated arrangement is
preferred. When the switch is in position 1, which occurs only for one
minute each hour, the dwell time is insufficient for drift to occur, and
the recorder accurately indicates the voltage of the rock.
Graphic -
Figure 1
Results:
1.) The chart shows a succession of vertical lines one hour apart, the
tops of which indicate the rock voltage at that hour.
2.) It is interesting to note the surprising activity and the change of
voltage with time.
3.) It is the cyclic behavior, with its' cosmological implication, which is
significant and requires explanation.
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