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

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EARTH'S SHIFTING CRUST
side may have been nonglacial. Thus sediment of both kinds
could be deposited in different parts of the Ross Sea at the
same time, depending, perhaps, to some extent, on the local
peculiarities of bottom topography and bottom currents. It
cannot be assumed, of course, that the outlines of the continent,
or the depths of the surrounding oceans, were the same
at that time as they are now. However, those who may still
be inclined to discount the theory presented in this book
must be reminded that all the phenomena discussed in this
chapter and all the principal phenomena discussed in this
book have been hitherto unexplained. It is not a question
of choosing between explanations. There is, at the present
time, no other explanation than ours of these facts.
a. Cores from the San Augustin Plains
A good deal of evidence from other cores supports this suc-
cession of polar positions in Greenland and Hudson Bay.
Let us consider first a very interesting study recently made in
New Mexico. There a group of scientists have been studying
a very long sedimentary core taken from the San Augustin
Plains. On these plains, sediments have accumulated to a
great depth without consolidating into rock, so it has been
possible to bore down about 645 feet and get a cross section
of all the deposits to that depth. These sediments contain
pollen of various trees and plants, which, as is well known,
does not easily disintegrate, but remains preserved in the soil
for very long periods. In this core, different kinds of pollen
in the different layers indicated changes in the species of trees
and plants growing in the region, and of course changes in
the kinds of plants growing in a region indicate changes of
climate. For the upper and most recent part of the core, it
was possible to use the radiocarbon method to date the
changes in pollen types, and therefore in climate.
Figure VIII (opposite page), prepared by Drs. Clisby and
Sears (84), shows the climatic curve for the upper 330 feet
of the core. The radiocarbon date at 27,000 years ago plus