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

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EARTH'S SHIFTING CRUST
might, under other circumstances, produce a doming up of
the crust in a local area or a lava flood.
p. Changing
Sea Levels
An important problem closely related to that of mountain
building is that of the cause of very numerous, and in some
cases radical, changes in the elevations of land areas rela-
tively to the sea level. Umbgrove finds that mountain folding
has been related, in geological time, with uplift of land areas,
or with withdrawal or regression of the sea (430:93). How-
ever, it is clear that the uplifts were not confined merely to
the folded areas, that is, to the mountains themselves, but
affected large regions. Such uplifts, where whole sections of
the earth's crust were elevated without being folded, are re-
ferred to as epeirogenic uplifts, to distinguish them from the
uplifts of the folded mountain belts which may have resulted
from the folding itself, and which are referred to as
orogenic uplifts. As to the extent of the resulting changes in
sea level, Umbgrove says:
. . . The most important question concerns the depth to which
the sea-level was depressed in distinct periods of intense regression,
in other words, the extent of the change to which the distance be-
tween the surface of the continents and the ocean floors was subjected
during the pulsating rhythm of subcrustal processes. Joly was the
only one who approached this question from the geophysical side,
and he arrived at an order of 1000 meters. . . . (430:95).
It becomes necessary, therefore, to find a connection be-
tween the cause of the folding of the crust and the cause of
general, or epeirogenic, changes
of elevation of continents
and sea floors. Fortunately, this problem is not really so diffi-
cult as it may seem at first glance. That it can be solved in
terms of the assumption of displacements of the earth's crust
is, I think, clear from the following considerations.
Gutenberg has pointed out that if a sector of the crust, in
gravitational equilibrium at the equator, is displaced pole-