Depletion of Earth's Magnetic Field | The Institute for Creation Research

IMPACT
Depletion of Earth's Magnetic Field

There are three important force fields associated with planet
earth, a gravitational field, an electric field, and
a magnetic field. The gravitational field attracts us to
the earth, preventing us from flying off into space as the earth
rotates. The earth's electric field is very unstable, producing
electric storms from place to place and at unpredictable times.

The earth's magnetic field is due to a huge electric, current,
billions of amperes, circulating in the core of the earth. But
the main complication lies in the fact that there are a multitude
of extraneous sources which produce distortions in the magnetic
field. As a consequence, the earth's magnetic field is very complex.
The instability sometimes shows up as tremendous magnetic storms,
blocking out transoceanic radio transmissions. There are all kinds
of anomalies resulting from distortions in the magnetic field.
There are many unpredictable variations in the magnetic field
with time and location.

Navigators do not depend on their magnetic compass as much now
as in early days. When navigators do use the magnetic compass
they have up-dated magnetic charts to provide corrections for
gross deviations in the earth's magnetic field from place to place
over the globe. This helps them correct their bearings for "false"
directions indicated by the compass, but the charts can not correct
for all the distortions.

In spite of all the distortions of the magnetic field there are
modern data-reductions methods of taking an epoch of worldwide
data and "washing" out the "noise" (distortions)
and obtaining the basic field. The basic field is that field produced
by the current circulating in the core of the earth. This basic
field is called the dipole field. It is similar to the
magnetic field of a single magnet located near the center of the
earth and having a north and south pole, hence the name dipole.
It is sometimes referred to as the earth's main magnetic
field.
The dipole magnetic field is the magnetic field of
interest in this paper.

RAPID DECAY OF THE EARTH'S MAGNETIC FIELD

It is known that the earth's magnetic field is decaying faster
than any other worldwide geophysical phenomenon. A comprehensive
ESSA Technical Report1 gives the values of the earth's
magnetic dipole moment (the vector which gives the strength and
direction of the magnet) ever since Karl Gauss made the first
evaluation in 1835. The evaluations have been made about every
10 or 15 years since then. Each evaluation required accurate worldwide
readings over an epoch (a year or so) and special mathematical
reduction to "wash" out the "noise." These
reliable data clearly show this relatively rapid decay. The report
stated that on a straight line basis the earth's magnetic field
would be gone in the year 3991 A.D. But decay is exponential and
in this case has a half-life of 1400 years.

A relatively recent NASA satellite preliminary report shows a
rapid decay in the earth's magnetic field. No knowledgeable scientist
debates the fact of the rapid decrease in the earth's magnetic
field, nor does he question that the associated electric current
in the core of the earth is using up energy. The present rate
of loss is seven billion kilowatt hours per year. The earth is
running out of that original energy it had in its original magnetic
field.

PREDICTABLE DEPLETION OF

THE EARTH'S MAGNETIC FIELD

The original source of the earth's magnetic field was the original
electric current circulating in the core of the earth. No one
knows how that electric current got started any more than one
knows why the earth was originally spinning on its axis. The two
are not related but they are both original states of the earth.

The electric current and its associated magnetic field have been
decaying ever since the origin of the earth. One might ask why
the current did not die out faster? Faraday's induction law prevented
it from dying out faster. As the magnetic field diminishes it
induces a voltage which opposes the decay, extending its life-time.
The large scale of this phenomenon accounts for such an extended
life. The radius of the core of the earth is 3.473 x 106
meters. The total physics of this problem is formidable but it
has been solved.2,3 The solution predicts the decay.
It yields the half-life equation:

Half-Life = 2.88 x 10 -15
(Conductivity) (Radius)

where the half-life is in years, the radius in meters, and the
conductivity is in mhos/meter.

Sir Horace Lamb came up with the equivalent of this equation
in 1833. As mentioned in the previous section, statistical analysis
of the data yields a half-life of 1400 years. Lamb did not have
a good value for the conductivity and therefore could not make
a good prediction, but he did know that it would last for thousands
of years, and that it was a plausible explanation of the earth's
magnetic field. It is still the only good theoretical/mathematical
explanation. Now it can be used to evaluate the electric conductivity
of the core of the earth, because the data show a 1400 year half-life.
The value of the electric conductivity of the core is, from this
equation, equal to 4.04 x 104 mhos/meter. This is a
very reasonable value for molten iron under the temperatures estimated
for the earth's core. This is the only good means of making that
evaluation of the conductivity of the earth's core.

Working backwards in time many thousands of years, this equation
yields an implausibly large value of the magnetic field and of
the electrically generated heat stored in the earth's core. (See
ICR Technical Monograph: Origin and Destiny of the Earth's
Magnetic Field
4) A reasonable postulate was shown
therein to yield an upper age limit of 10,000 years.

REFUTATION OF THE REVERSAL HYPOTHESIS

To protect their long-age chronology, evolutionists hold to a
reversal hypothesis. The magnetic field is said to have remained
at essentially the same value during geologic time, except for
intervals in which it went through a reversal, dying down to zero
and rising up again with the reverse polarity. The last reversal
is supposed to have taken place 700,000 years ago.

The reversal hypothesis has no valid theoretical support. That
is acknowledged in a recent Scientific American article: "No
one has developed an explanation of why the sign reversals take
place. The apparent random reversals of the earth's dipole field
have remained inscrutable
."5 Neither are there
any dependable data to support the reversal hypothesis. Reference
has already been made to the multitude of magnetic disturbances,
"noise," that make it so difficult to evaluate the earth's
magnetic dipole moment, even when using absolute measurements
over the whole earth. Yet it is absolutely essential that one
evaluate the earth's magnetic moment if he is to claim to know
the state of the earth's magnet at that time.

The tremendous amount of data on magnetic anomalies is important
in exploration because they are evidences of the nonuniformities
where one might expect minerals, etc. But they are useless insofar
as history of the earth's dipole magnet is concerned.

In reference to the claims that the magnetization patterns on
the sea floor relate to a history of the earth's magnetic field
and continental drift, A.A. and Howard Meyerhoff give a lengthy
refutation and very firmly conclude: "The so-called magnetic
anomalies are not what they are purported to be—a 'taped record'
of magnetic events during the creation of the new ocean floor
between continents
."6

One of the factors that makes rock magnetization completely undependable
as evidence for the so-called reversals is the self-reversal
process that is known to exist in rocks, totally independent of
the earth's magnetic field. Richard Doell and Alan Cox state that:
"The reversed magnetization of some rocks is now known
to be due to a self-reversal mechanism. Moreover, many theoretical
self-reversal mechanisms have been proposed … However, in order
definitely to reject the field-reversal hypothesis it is necessary
to show that all reversely magnetized rocks are due to self-reversal.
This would be a very difficult task since some of the self-reversal
mechanisms are difficult to detect and are not reproducible in
the laboratory
."7 It is interesting to note
that these authors attempt to shift the burden of proof to the
opponents of the reversal hypothesis but in so doing they demolish
the reliability of the very data upon which they depend.

J.A. Jacobs states that: "Such results show that one
must be cautious about interpreting all reversals as due to a
field reversal and the problem of deciding which reversed rocks
indicate a reversal of the field may in some cases be extremely
difficult. To prove that a reversed rock sample has been magnetized
by a reversal of the earth's field, it is necessary to show that
it can not have been reversed by a physico-chemical process. This
is a virtually impossible task since physical changes may have
occurred since the initial magnetization or may occur during certain
laboratory tests
."8

A strong conflict is exposed when a direct comparison is made
between 1) the real-time evaluations of the magnetic dipole field
by Gauss et al, and 2) the magnetic "field" evaluations
deduced following evolutionary assumptions about the magnetization
in rocks and artifacts.

Over the last two centuries the work of Gauss et al has shown
a continuous depletion of the earth's magnetic field. That is
generally accepted as fact, whereas the magnetized rock-artifact
method fails to show any trace of this trend. 9

CONCLUSION

The only valid theoretical mathematical explanation and the only
tenable data support the conclusion that the earth's magnetic
field was created with a sizable amount of original magnetic energy
and has been continuously decaying ever since and that it is headed
for extinction in a few thousand years. Looking backwards in time
there is a limiting age because there is a limit as to how much
magnetic energy the earth could have had originally. Reasonable
postulates as to the maximum magnetic field the earth could have
had limit its age to a few thousand years.

The reversal hypothesis which has been proposed to extend the
magnetic field back billions of years has neither a valid theoretical/mathematical
basis nor observational support. The paleomagnetic data upon which
it depends for support do not correlate with the state of the
earth's magnetic field, namely its magnetic moment.

REFERENCES

1. McDonald, K.L. and R.H. Gunst, Earth's Magnetic
Field 1835
to 1965, ESSA Tech. Rept. U.S. Dept. Com., 1967,
pp. 1 & 5.

2. Lamb, H., Phil. Trans., London V. 174, 1883, pp. 519-549.

3. Barnes, T.G., Creation Research Society Quarterly, Vol. 9 (1),
1972, pp. 47-50.

4. Barnes, T.G., Origin and Destiny of the Earth's Magnetic
Field,
ICR Tech. Mon. No. 4, 1973.

5. Carrigan, C.R. and David Gubbins, "The Source of the Earth's
Magnetic Field," Sci. Amer., Feb. 1979, p.
125.

6. A.A and Howard Meyerhoff, "The New Global Tectonics",
Amer. Assoc. Petr. Geolo., Bul. V. 56 (2), 1972,
p. 337.

7. Doell, Richard and Allan Cox, Mining Geophysics, V.
11, Soc. Expl. Geophysicists, 1967, p. 452.

8. Jacobs, J.A., The Earth's Core and Geomagnetism, MacMillan,
pp. 105-106.

9. Burlatskaya, S.P., "Change in Geomagnetic Intensity in
the Last 8500 Years," Inst. of Terrestrial Physics, USSR
Acad Sci., 1969, p. 547.