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

382
EARTHS SHIFTING CRUST
on account of this that Einstein regarded the theory of isos-
tasy as itself unreasonable (128). According to our theory,
Greenland possibly was deglaciated during the period of the
Wisconsin icecap in North America, and therefore the ice-
cap there may be recent, and isostatic adjustment poor,
There are a few indications that the pressure of the Ant-
arctic cap (possibly reinforced by the Greenland cap) has
already begun to disturb the stability of the earth's crust.
These consist of recent seismic movements.
In the study of earthquakes, specialists have distinguished
between them not only according to their scale but also by
a qualitative difference that appears to exist between those of
minor and those of major magnitudes. Minor earthquakes,
which occur daily in considerable numbers, are considered
to be of local origin. They are merely episodes in the perpetual
process of adjustment of strains
arising from local causes.
in the earth's crust
Some of the major earthquakes, on the other hand, are
considered to be qualitatively different. Benioff, for example,
suggests that these major earthquakes are not related to local
causes of any sort, but result from the operation of what he
calls "world-wide stress systems" (29) in other words, from
pressures applied
to the earth's crust as a whole. So far as I
know, no geologist has advanced an explanation for these
world-wide pressures; it seems quite possible that they may
be related to the icecap pressure that, according to our view,
has been increasingly exerted on the crust for thousands of
years.
Benioff draws attention to a fact that appears to confirm
this supposition. He points out that in recent decades there
has been an increasing tempo of major earthquakes; they
appear to be coming closer together and increasing in violence.
He cites especially the great quakes of 1904, 1924,
1 935> 1 94> and 1950 (29:335). If the Antarctic icecap is the
major cause of these quakes, we can understand the increase
in their frequency and intensity, which may result either
from the increase of the quantity of Antarctic ice or from