The topological fits between the continental shelves
on opposing sides of the various oceans, and particularly the Southern Atlantic, would seem to be too close for pure
chance. That the sediments immediately above the first basalt layers get older
as the distance from the mid-oceanic “spreading zone” increases, strongly
supports the idea of new ocean crust being formed from an upwelling of magma
into the fissures being created when the “plates” are torn apart. Evidence of
matching bands of new crust either side of the “spreading zone”, located in
time by changes in magnetic signatures that have been locked-in when the magma
hardened, is by many considered the pivotal evidence that the “plates” are
being pulled apart to allow the creation of new mid-ocean crust. The
concentrations of seismic and volcanic activity around the spreading zones and
their complementary “subduction zones”, where the newer ocean crust is thought
to be pushed beneath the relatively older continental crust, is consistent with
the fundamental ideas of PT. So too are the matches in certain floral and
faunal fossil remains within the continental crusts on opposing sides of oceans
believed to have once formed a larger continental land mass split asunder by
the processes of PT. In some cases there are even matches in existing living
species on continents too far apart to have allowed natural spreading. All of
this and much other carefully gathered data, creates a model that is beguiling
in its simplicity and convincing in its consistency. And yet there are
increasingly recognised factors that do not seem to fit into this apparently
self-consistent and compelling model.
In the following posts some of the serious geological
evidence that does not appear to fit in with the basic ideas of PT will be
briefly summarised. This critique has relied heavily upon the excellent
summaries of critics such as Pratt (2000) and Meyerhoff et al (1996). It has
also been bolstered by the increasing body of evidence being presented by Choi,
Dickins, Smoot et alia in the publication New Concepts in Global Tectonics (NCGT),
an e-publication explicitly set-up to allow the airing of evidence that is
contrary to the ideas of PT and which it seems has too often been
suppressed by the dominant publications in the field. Some of the alternative explanations that have
been put forward for the source of energy required to drive the dynamic
processes of the Earth’s crust will be briefly touched upon. However, the main
purpose of this and the following posts is to put forward an alternative model for the processes that
might have been and continue to be at work in shaping the Earth’s crust. It
will be argued that this new model is not only able to account for most of the
processes and observations currently cited as evidence in support of PT but is
also seemingly able to overcome most of its identified serious deficiencies. In
particular, this new model will be demonstrated to be consistent with the
evidence that vertical crustal motions are and have been as critical as
horizontal motions in shaping our planet. Furthermore, the horizontal movements
required for this new explanation are considerably less than those needed for
PT. At temporal and spat ial scales
many orders less it has already been suggested that similar dynamic processes continue
to shape periglacial environments both on Earth and some of the other planets
and their satellites within the solar system.
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