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

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EARTH'S SHIFTING CRUST
movement until the arrival of an oceanic area (in this case,
the Arctic Ocean) at the pole. As to the second fact that, ac-
cording to Coleman, was established by Low, I shall suggest
an explanation later (Chapter VIII).
). The Cause of the Oscillations of
the Cause of the Climatic Optimum
the Ice Sheet and
But what about the alternating phases of retreat and readvance
of the ice sheet? The retreats can be explained, of
course, by the assumption that the icecap was moving slowly
into lower latitudes with the displacement of the crust. But
how are the readvances to be explained? Up to the present
there has been no explanation for these.
I have already suggested that a corollary of any crust dis-
There have
placement is an increase of volcanic activity.
been times in the past, however, when the quantity of vol-
canic action has been extraordinary (231:629). As an exam-
ple of this, there appears to be evidence that in a small area
of only 300 square miles in Scandinavia during Tertiary
times there may have been as many as 70 active volcanoes at
about the same time. Bergquist, who cites the evidence, re-
marks, "Volcanic activity on this scale, erupting through
about 70 channels, and concentrated in a relatively short
period, must have been very impressive" (31:194).
It seems likely that a phase of intense volcanism would be
favored where a sector of the crust was moving
toward the
equator, and undergoing stretching (or "extension") together
with widespread fracturing, for we must remember that this
pulling apart of the crust would permit the release of many
pre-existent strains, the upward or downward adjustment of
blocks that had been held out of isostatic adjustment for a
longer or shorter time. There would certainly be a general
rise of igneous matter into millions of new fractures, and
occasionally this could result in overflows at the surface, in-
cluding, as has already been pointed out, vast lava floods.