Greinar (Vísindafélag Íslendinga) - 01.01.1977, Blaðsíða 133

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gressions and global stresses of climatic origin, on the other.
These stress fields can express themselves in phases of moun-
tain building and in many other tectonic ways, as well as in
volcanic manifestations, Chapter 3.
The idea is not new that at depth there must be some medi-
um, which has the capability of alternately expanding and con-
tracting, and so cause extensive uplifts or lowerings, especially
of continents but possibly of ocean bottoms too. Du Toit (99)
speaks of the paramorphic zone, a concept going back to
Fermor in 1913. It is postulated that in this zone polymor-
phism is possible, but that was not found to be in agreement
with laboratory work, when the latter came to the fore. Lester
King (87) also postulates a medium that causes wide wave-like
uplifts on continents, and calls the process cymatogeny (87,
p. 191). V. V. Beloussov (100) has also stressed the fact,
that certain large areas within the USSR have repeatedly
been uplifted between periods of lower stand, and one must
be completely ignorant of geology, not to understand how such
conclusions can be based on solid facts and sound reasoning
by reference to fundamental principles of geology. Beloussov
has insisted upon some process in the Upper Mantle, capable
of explaining this phenomenon. He has also stressed that cer-
tain seas with a typical oceanic crust, i.e. a shallow Moho,
were not so long ago parts of continents. Due to our intro-
duction of dense nanocrystals this would now be no violence
of isostasy.
Beloussov (l.c.) also points out areas, where isostasy is
apparently not valid: “Bulges without roots” into the mantle,
and depressions without corresponding “antiroots” or eleva-
tion of the Moho. In this connection one should keep in mind
that changes of the oscillating nanocrystalline state are practi-
cally momentuous, whereas the attainment of isostatic equili-
brium takes a considerable time, even tens of thousands of
years, and thus lags behind the changes of the Moho. The lack
of a root of a bulge, may just mean that the bulge is sinking,
perhaps not measurably, when a seashore does not reach it.
The lack of an “antiroot” could similarly mean unmeasurable