Thomas Barnes wrote:
"On the other hand, the presumed dynamo theory has no substantive theoretical
basis and no definitive predictive value. Its presumed reversal mechanism
has admittedly remained inscrutable." Thomas Barnse, "Earth's Magnetic Age:
Impact No. 122, August 1983, p. iv.
Other creationists picked up the argument. Henry Morris wrote:
"The analysis developed by Dr. Barnes is based on sound physics
careful calculations, and solid data. The dynamo theory, and the
fluctuating and reversing magnetic field concept (except on a localized
basis), are little more than ad hoc notions, with no sound basis in either
theory or measurement. The only real reason for rejecting the
first and accepting the second is that the first supports recent
special creation; the second tries to salvage a bankrupt
evolutionary uniformitarianism."~ Henry M. Morris and John D.
Morris, Science, Scripture, and the Young Earth, (El Cajon:
Institute for Creation Research, 1989), P. 55
Scott Huse wrote:
"Unfortunately for evolutionary scientists, the reversal hypothesis
has absolutely no valid scientific theoretical basis. Furthermore,
rock magnetism cannot be used to support these so-called reversals
because there is a self-reversal process known to exist in rocks,
completely independent of the earth's magnetic field."~Scott M.
Huse, The Collapse of Evolution, (Grand Rapids: Baker Book House,
1983), p. 22
With such certainty one would naturally assume that scientists would be
unable to come up with a mechanism for geomagnetic reversals. But, they
finally have one. But I might point out, that the sun reverses its magnetic
field every 11 years so such a phenomenon has been observed.
Glatzmaier and Roberts of their earth magnetic dynamo model, write:
"A three-dimensional, self-consistent numerical model of the
geodynamo is described, that maintains a magnetic field for over
40,000 years. The model, which incorporates a finitely
conducting inner core, undergoes several polarity excursions and
then, near the end of the simulaiton, a successful reversal of
the dipole moment. This simulated magnetic field reversal shares
some features with real reversals of the geomagnetic field, and
may provide insight into the geomagnetic reversal
mechanism."~Gary A. Glatzmaier and Paul H. Roberts,"A Three-
Dimensional Self-Consistent Computer Simulation of a Geomagnetic
Field Reversal," Nature, Sept. 21, 1995, p. 203.
**
"Our present solution, with a finitely conducting inner
core, spans > 40,000 years, more than three magnetic diffusion
times, with no indication that it will decay away, which is
suggestive evidence that our solution is a self-sustaining
convective dynamo. The solution begins with random small-scale
temperature perturbations and a seed magnetic field. After an
initial period of adjustment (~10,000 years) during which the
dipole part of the field gradually becomes dominant, our time-
dependent solution maintains its dipole polarity until near the
end of the simulation, when it reverses in little more than 1,000
years and then maintains the new dipole polarity for roughly the
remaining 4,000 years of the simulation."~Gary A. Glatzmaier and
Paul H. Roberts,"A Three-Dimensional Self-Consistent Computer
Simulation of a Geomagnetic Field Reversal," Nature, Sept. 21,
1995, p.204
**
"The field at the surface has a dominantly dipolar structure
before and after the reversal, with the dipole axis nearly
aligned with the rotation axis, which is vertical in Fig. 1.
During the polarity transition the field structure at the surface
is much more complicated and the dipole axis passes through the
equatorial plane."~Gary A. Glatzmaier and Paul H. Roberts,"A
Three-Dimensional Self-Consistent Computer Simulation of a
Geomagnetic Field Reversal," Nature, Sept. 21, 1995, p. 205-206
**
To compare our simulated reversal with the palaeomagnetic
reversal record we now describe how our reversal appears as
observed locally at different sampling sites at the surface....By
monitoring the rate of change of our surface field direction at
these 50 sites we find the largest rate (at one site, at one
time) to be 0.1o per day. But most sites have a maximum rate of
~0.01o per day during the reversal, which is larger than the rate
observed in the secular variation of the present-day geomagnetic
field but much less than the impluse of 6o per day inferred from
the Steens Mountain record, the largest rate seen in the
palaeomagnetic reversal record."~Gary A. Glatzmaier and Paul H.
Roberts,"A Three-Dimensional Self-Consistent Computer Simulation
of a Geomagnetic Field Reversal," Nature, Sept. 21, 1995, p. 208
**
To base our rejection of evolution on a "lack of mechanism" may lead to the
same type of disproof as the "lack of reversal mechanism."
That argument is very weak.
glenn