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

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EARTH'S SHIFTING CRUST
upper atmosphere to be distributed around the world. Apparently,
the amount of dust produced by the eruption of
Mt. Katmai in Alaska in 1912 was sufficient slightly to lower
the temperature of the whole earth's surface for a period of
two or three years (87:270; 231:569). For long-range effects
a continuous series of explosions would be necessary, because
volcanic dust settles out of the atmosphere in periods of the
order of three years. Humphreys presents a great deal of evi-
dence correlating variations in average annual global tem-
peratures through the nineteenth century, with specific volcanic
eruptions. He establishes the fact that the eruptions
certainly had an important influence.
If this is true of our times, what should we expect to result
from the activation of very great numbers of volcanoes dur-
ing a displacement of the crust? Not only would the temperature
fall, and perhaps very drastically, but continuing vol-
canic outbursts would keep it low. At the same time, the
alternation of periods of massive outbursts with periods of
quiet would produce violent variations of the climate, between
extremes of cold and warmth.
Here we have our explanation of the five or six major
readvances of the Wisconsin ice sheet (there were, appar-
ently, many more minor ones). In all probability, they resulted
from the long continuation of massive outbursts of
volcanism. The readvances of the ice are explained by vol-
canism, and the volcanism is explained by the displacement
of the crust.
It is not necessary, however, for us merely to assume with-
out evidence that there must have been unusual volcanic
activity at the end of the ice age. On the contrary, there is a
rather remarkable amount of evidence of excessive volcanism
It comes from
during the decline of the Wisconsin icecap.
many parts of the earth. For North America it is particularly
rich. From radiocarbon dating we have learned that during
the last part of the ice age there were active volcanoes in our
northwestern states. One of the greatest eruptions was that
of Mt. Newberry in southern Oregon less than 9,000 years