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

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EARTH'S SHIFTING CRUST
occurred in comparatively narrow areas. The Hawaiian
Islands, for example, represent a long, narrow segment of the
crust. Obviously the crust can support loads with small span
more easily than loads with a very great span. These devia-
tions, therefore, may not tell us much about the gravitational
status of the Antarctic icecap, which, of course, has an enormous
span, since it covers a whole continent. Since they are
insignificant quantitatively as compared with the possible
effect of the continental icecap of Antarctica, they will not,
of themselves, answer Einstein's question.
Of more importance are isostatic anomalies of broad span,
and these are, surprisingly, quite plentiful. Daly mentions
one along the Pacific coast. This is a negative anomaly
a deficiency of mass. Daly explains that according to one
formula (the "International Formula"), it covers an area
2,100 miles long, and 360 to 660 miles wide; according to
another formula (the "Heiskanen"), it is reduced to one half
both in intensity and in extent (97*371). Taking the lesser estimate,
the deficiency of mass over this large area still amounts
to the equivalent of a continuous ice sheet 1,000 to 1,200 feet
thick. So it appears that over this large span the crust can bear
that amount of negative weight (that is, of pressure from with-
in the earth) without giving way, at least for a short period of
time. In other parts of the United States there are positive
anomalies of the same magnitude, and these obtain over large
areas.
A far more extraordinary case is an enormous area of nega-
tive mass that covers part of India and most of the adjacent
Arabian Sea. The width of the negative area in India is 780
miles. Daly, after noting the challenge presented by this
fact to the whole theory of isostasy, goes on to say:
The situation becomes even more thought provoking when we
remember that Vening Meinesz found negative Hayford anomalies
all across the Arabian Sea, 2500 kilometers in width. Apparently,
therefore, negative anomalies here dominate over a total area much
greater than, for example, the huge glaciated tract of Fenno-Scandia
[Finland and Scandinavia]. And yet there is no evidence that the