The Earth's Shifting Crust by Charles Hapgood - wire of information

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EARTH'S SHIFTING CRUST
unsolved problems of geology. It is connected with our phase
of equatorward crust displacement. It has to do with the
filling of the fractures by molten magma from below. Camp-
bell considers that this filling of the fractures is the first step
in mountain building, or at least in the formation of a
geosyncline. Obviously, it is possible to start the process at
other points; this is therefore only a matter of convenience,
and for the purpose of drawing a clear picture of the process
for the reader. But Mr. Campbell points out that the process
of the filling of the cracks, and the later solidification of the
intruded material, adds extension to the crust; there is now
more surface. When, in future shifts of the crust, this area
passes over the equator toward a pole, or moves poleward
from where it is, the extended surface has to yield to the
resulting compression by folding more than it would have
had to do had there been no molten intrusions in the first
place. It is, therefore, reasonable to call this the first step in
mountain building, although there is as yet no folding, and
no uplift of the rock strata.
But this question of molten intrusions into the crust raises
another sore point. It has been, until now, a very difficult
thing to explain the rise of molten matter into the crust.
Geologists have speculated as to what force could have shot
up the molten matter that formed the innumerable "dikes"
and "sills," as the resulting veins are called. They have not
been able to agree upon the question. No reasonable ex-
planation of these millions of magmatic invasions of the crust
has been found.
Of course, it is realized that the crust of the earth is, in a
sense, a floating crust. The materials of which it is composed
are lighter, it is assumed, than the materials below, and are
solid, as compared with the plastic or viscous state of the
underlying layers. The crust can be thought of as floating
in hydrostatic balance in the semiliquid lower layer. This is
generally understood among geologists. It follows logically
from this that, if two or more blocks of the crust got separated
with cracks between them, the "molten" material