[GB: Readers have been asking
us to review the Expanding Earth Theory. Although that is a bit removed from
our usual focus on regressive physics and cosmogony, PSI member Bill Howell, a
professional geologist, has consented to do the job. His review consists of
three parts.]
Bill Howell
Part 3: Possible Synthesis of the EET
and PTT Models
5) Assessment
of the Expanding Earth and Plate Tectonic Models
It seems to me that the only
reason for Maxlow to propose that solar plasma somehow created an additional 50
percent of the Earth’s mass (in only the past 200 million years) and the only
reason to ignore the seismic evidence for deep crustal subduction, is to
support the hypothesis that the Earth’s radius has expanded. But it also seems to me that the only reason
to even need that hypothesis is because the continents can seem to be fitted
together into a single landmass that encompasses the globe by reducing the
Earth’s radius in half.
Although this causal chain of
thought is not irrational, it reminds me of the Ptolemaic method of building
epicycles upon epicycles. There is a
simpler ‘alternative interpretation’ than an expanding Earth radius that can
account for the existence of such a single landmass, but which also accepts
subduction and a constant Earth radius.
In the remainder of this essay I will describe this alternative
interpretation and provide some facts, interpretations, and speculation that
support its validity. But it does get a
little complicated...
During the 1950’s, there was
no professional consensus on how the ocean basins had formed nor any consensus
that the continents had once been joined together, and mantle convection was
considered a radical hypothesis not widely accepted by geologists and
geophysicists. But new geophysical data
forced the geological community to reconsider Alfred Wegner ’s
continental drift hypothesis, which had previously been dismissed because a
possible mechanism for moving the continents across the ocean basins could not
be found.
During this period of
reassessment, serious scientific consideration was also given to the concept of
an expanding Earth by Australian geologist Warren Carey (who
subsequently inspired Dr.
Maxwell ’s interest in EET). Carey
had initially supported the concept of continental drift but later proposed
that an expanding Earth could also explain the data. Interestingly, Carey
believed that only a cosmological perspective would provide a final solution to
the problem [4].
Some of the new data that were obtained during this time were collected by the geophysicist Vening Meinesz . Meinesz conceived of a model that H. H. Hess later developed into a 1962 paper titled History of
Ocean Basins [7]. This paper
subsequently acquired the nickname: ‘An Essay in Geopoetry’ and it is credited
with leading the scientific community toward the theory of Plate
Tectonics.
The Meinesz-Hess model
involved a unique event early in the history of the Earth that Hess called the
“great catastrophe”. It proposed that a
single convective cell within the Earth’s interior had overturned. This resulted in the formation of a
nickel-iron core as denser materials descended toward the core, and
lower-melting and lower-density silica-rich material was extruded onto the
surface to form a single primordial continent. An apt analogy is slag that will rise to the
surface of a vat of molten material when metal is being extracted from ore by
smelting. Another analogy, which
incorporates the effect from the Earth’s rotation, is what occurs when a fluid
is spun in a centrifuge and the lighter materials are separated out. Figure 5, which is taken from Hess ’s
1962 paper, illustrates his concept of the “great catastrophe”.
Figure 5
Single cell (toroidal) Convective Overturn of Earth’s
Interior
(After Vening
Meinesz , 1952, from H.
H.
Hess, 1962: History of Ocean Basins)
In this ‘essay in geopoetry’,
Hess wrote: “It is postulated that this heat and a probably much larger amount
of heat resulting from the energy involved in the accumulation of the Earth
were not sufficient to produce a molten Earth... The proposed single-cell overturn brought
about the bilateral asymmetry of the Earth, now possibly much modified but
still evident in its land and water hemispheres. After this event, which segregated the core
from the mantle, single-cell convection was no longer possible in the Earth as
a whole”. (Note: in using the term
‘bilateral symmetry’, Hess is referring to the
topographic elevation difference between the continents and ocean basins).
Hess went on to write that:
‘On the basis that continental material is still coming to the surface of the
Earth from the mantle at the rate of 1 km3/year, accepting Sapper's
(1927, p. 424) figure on the contribution of volcanoes over the past 4
centuries, and assuming uniformitarianism, this means 4 x 109 km3
in 4 aeons or approximately 50 per cent of the continents. So we shall assume that the
other half was extruded during the catastrophe’ (emphasis added).
By removing the ocean basins,
Dr. Maxlow ’s model
can reduce the present radius of the Earth by 50 percent; however, Dr. Maxlow
has also constructed models that join continental crust together that are much
older. These models are based on the
continental cratons that are the oldest crustal material found. Cratons are billions of years old and are
thought to be the original nucleus of all continental landmasses. Dr. Maxlow writes (on page 57) that by
removing all seafloor volcanic, continental sedimentary basin sediments and
magmatic rocks, and any remnant Proterozoic orogenic rocks, his model can be
extended back to the early Archaean (1,600 million years ago), and the
remaining cratonic landmasses can be assembled into a single landmass
encompassing the globe that reduces the size of the Earth by another 50
percent, or to about 27 percent of the Earth’s present radius.
What Dr. Maxlow
is saying then, is that the aerial extent of the continental landmasses during
the Archaean is about 50 percent of the aerial extent that we see today. Interestingly, this 50 percent reduction
coincides with the volume of the primordial landmass that Hess
assumed had originally been extruded during the ‘great catastrophe’. So both Hess and
Maxlow are suggesting that the original primordial cratonic landmass of the
Earth was about 50 percent of the landmass that presently exists. In order for this landmass to encompass the
globe, Maxlow interprets this to mean that the Earth’s radius during the
Archaean was even smaller than it was during the Jurassic, while Hess
interprets this to represent the volume of landmass that was extruded from the
Earth during the ‘great catastrophe.’ In other words, Hess and Maxlow simply
have different interpretations about what the data mean.
6) Conclusions Regarding
the Validity of the Expanding Earth Theory
It seems to me that the
fundamental factor that drives the EET is that it’s possible to reassemble the
continents into a single primordial landmass, and that these ‘data’ are what led
to the interpretation that the Earth’s radius has expanded over time. The Meinesz-Hess model indicates that an
overturning of the Earth interior could account for the same primordial
landmass without requiring an expanding Earth.
Although the idea of a single primordial landmass is apparently a current
controversy within PTT, such a concept is not a fundamental problem. PTT simply interprets the ‘data’ (and
evidence) to explain the shapes and positions of the continents using the
process of subduction instead of interpreting it to mean that the Earth’s
radius has expanded.
So it seems to me that the
EET and PTT models are not in conflict with regards to the continents having
once been assembled into a single landmass.
And if the Meinesz-Hess model is accepted, then there is also not even a
controversy regarding whether a primordial continental landmass once
existed. The controversy then, is
actually about how to interpret the data.
In my opinion, the evidence from deep earthquake foci, seismic
tomography, geodetic and gravimetric data, paleontology, and the missing mass
problem clearly support the interpretation of the PTT model and clearly
discredit the interpretation of the EET model.
End of Part 3
The synthesis proposed above
could resolve the controversy among expanding Earth believers. Of course, acceptance of the Meinesz-Hess
model requires that there was once a single “great catastrophe”. Meinesz developed his concept during the
1950’s based simply on the mathematics and geophysics of spherical
harmonics. He did not have any physical
evidence to support it. The study of the
rocks brought back from the Moon landings appears to provide that supporting
physical evidence. But that is a
Geostory for another day.
References
[7] History of Ocean Basins, H. H.
Hess , Petrologic Studies - Princeton University , 1962
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