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

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EARTH'S SHIFTING CRUST
pears to suggest that displacements may have amounted, on
the average, to no more than a third of the distance from a
pole to the equator. If this is true, then the resulting uplift
to be expected should be of the order of about one third of
the uplift he suggested, or from 400 to 500 feet. We shall see,
later, how well this agrees with the evidence.
There is another factor that would operate in the same
direction as the effect mentioned by Gutenberg, to alter the
elevation of land areas and sea bottoms. Unlike the gravitational
effect, however, this second factor would tend to a
permanent change in sea levels, and might therefore, cumulatively,
result in important changes in the distribution of
land and sea. It is a question of the permanent consequences
of the stretching or compression of the crust. As we have
seen, an area displaced poleward must undergo compression
because of the shortened radius and circumference of the
earth in the higher latitudes. This compression must result
in the folding of rock strata, which will be likely to occur
mainly in areas where the crust has already been weakened
by the formation of geosynclines. The effect of the folding
will be to pile up the sedimentary rocks that have been
formed from sediments deposited in the geosynclines, caus-
ing them to form thicker layers. These thicker layers of
lighter rock will tend, even after gravitational adjustments
have taken place, to stand higher above sea level. The effect
of one displacement in this respect would be slight, but the
accumulation of the effects of many displacements through
millions of years could lead to extremely important changes
in the distribution of land and sea areas. Numerous displacements
of the earth's crust could, in fact, constitute an essen-
tial, and perhaps even the basic, mechanism for the growth
of continents.
Equally important for the general question of sea levels
are the effects to be expected from a displacement of a sector
of the crust toward the equator. Here the crust will be sub-
jected to tension, or stretching. We have already noted that
in this process innumerable fractures will be created in the