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

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EARTH'S SHIFTING CRUST
the United States Geological Survey. They were also studied
by Dr. Cesare Emiliani, who used a technique developed by
Dr. Harold C. Urey for determining ancient water temperatures.
This technique makes use of an isotope of oxygen
(Oi 8 ) the proportion of which in sea water is affected by
temperature. The temperature of the water at which ancient
shells grew (or, in this case, at which foraminiferal micro-
organisms grew) can be determined by the proportion of
Ois in the remains. This determination is independent of
time, and the temperature at which a shell grew 200,000,000
years ago (but not the date) can be determined just
as well
as if the shell grew last year. Emiliani used this technique to
establish temperature curves for the sedimentary cores for
the period within the range of radiocarbon. Then, using this
as a base, he extrapolated to the older parts of the cores.
There is reasonably good agreement between temperature
curves arrived at in this way and those obtained by the
ionium method.
Of the three cores taken from the North Atlantic and
dated by the ionium method, one extends back to only 1 1,800
years ago, one to 24,300, and one to 72,500. The longest core
will have the greatest interest for us (Figure IX).
Core P- 12 6(5) was taken in mid-Atlantic, approximately at
the latitude of Nova Scotia, in about three miles of water.
Since it extends back to 72,500 years ago, it should be able
to throw some light on the question of our assumed polar
positions, including the Alaskan.
The story of this core, as we recede into the past,
is as
follows: There is first a layer of volcanic glass shards, dated
about 12,800 years ago, then a layer of nonglacial sediment,
then glacial sediment from 14,700 to 23,700 years ago, then
nonglacial sediment but with evidence of cold water, back
to 60,700 years ago. This period of cold water is interrupted
by three brief intervals of glacial deposition, by two layers of
confused ("anomalous") sediments, and by a layer of volcanic
glass shards between 51,400 and 55,400 years ago. Then, between
60,700 and 68,000 years ago, the North Atlantic water