74
potassium and uranium. In the light of what has been stated above, it should
be connected, as far as the ores matter, to axial parts of oceans, with process
of silication intermetalic joints of the upper mantle. Admit the community of
sources for these elements and ores matter, and also the same cause of
conditionality of characteristic "failures" on the curve evolution potassion and
radiogenic strontium in Mesozoic-Cenozoic, it is possible to involve the data
of isotopic strontium for defining the time of the beginning of entrance ores
matter through the axial zone of oceanic couch. According to the curve,
reflecting variation of the relation strontium at ocean during the Phanerozoic
(Figure 7), the first portions of ores matter could begin to enter from the
end of late Jurassis time (150-140 Ma), and from the
beginning of Cenozoic the process of endure of ores matter has become more
intensive. However, we should keep in mind, that the given estimate is
received on waters of the World Ocean and, apparently, reflects the time of
occurrence ores matter in the Pacific Ocean depression. It was established
before other oceans and, accordingly, earlier in it the processes of ores
generation were caused by approach to the surface of the planet, the zone of
silication should have started. Other oceans could enter this stage of
development much later, therefore the fields of iron - manganese formations,
copper-nickel-cobalt, sulphide-polymetalic and others ores are less
developed.
Finishing the brief review of evolution of the oceans, it is necessary to
dwell on the problem of sources of water in the Earth. Some researchers
assume that water has space origin; other scientists admit the jevenilic source
of waters connected with the magmatic processes and volcanic degasation.
However, the appearance of oceans on the Earth since the middle Riphean
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time, their intensive development in Paleozoic and, especially in the
Mesozoic-Cenozoic period, makes it difficult to connect it to the mentioned
above sources of water. According to the hydridic conception, free water
would appear only in the degassing fluids when the silicate-oxide layer of the
planet was completely formed. This most probably occurred at the end of the
Archean, when the early, areal granulite, anhydrous metamorphism was
completely replaced by hydrous amphibolites. Thus, the superficial
hydrosphere had appeared and could permanently exist only from the end of
Archean. Since then the hydrosphere has steadily grown.
The scale of this growth in the Mesozoic and Cenozoic can be evaluated
with the aid of oxygen isotopes. Ocean water isotope distribution at present
is usually taken as the standard:
18
O=0 in seawater. If we make the
assumption that during the Mesozoic and Cenozoic, a 200 meter thick layer
of marine sediments with
18
O= +30 o/
oo
had accumulated, then 1000 meter deep layer of juvenile
water with
18
O= +6 o/
oo
should be added to the hydrosphere in order to
preserve the oxygen isotope distribution in the ocean water at the observed
lever. Thus, ocean volume would have had to increase approximately fifty
percent during this period (Larin, 1993).
From the positions of the hydridic conception, the cause of appearance
huge quantity of ocean water is the intensive decomposition of the hydridic
core in Phanerozoic and degasation of hydrogen, which during the process of
rising to the surface of the planet took out from mantle and lithosphere
oxygen. Both of these elements in the upper surface condition are connected
together forming the water, that filling the oceanic depressions, arising during
the expansion of the Earth.
CONCLUSION
The reduction of time intervals of the geological-tectonic cycles and stages
from the protoplanet stage until nowdays, based on the conception of the
primordial hydridic Earth, is explained by gradual decrease of volume the
hydridic core. Each cycle begins by warming up and decomposition of
hydrides in the external sphere of the internal core, that causes warming up
and increase the pressure of hydrogen in the external core. This process
causes degassation of hydrogen and subsequent decompression the external
zone of the core. Therefore, with each cycle the borderlines of the external
and internal core remove to the center of the planet at some certain interval.
But the volumes of matter involved in decomposition of the hydridic core
have shortly decreased from early cycles to the latest cycles. Consequently
the time of degasation and decompression should be reduced, to wit the
continuance of cycles of decomposition of hydridic core and correspondingly
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the tectono-magmatic cycles should be decreased. Nowadays, the internal
core makes less than 1 % of the volume of the planet, and it is natural to
suppose, that the faster expense of hydridic reserves in the core necessarily
will cause the contravention of habitual cycles in future of the Earth. In this
plan it is possible, that the Alpine cycle are the last full processed
geodynamic cycle of the development of the Earth. One may be suppose that
the present stage is transitive to a new type of the geodynamic regime, which
will come from the moment of complete depletion of the hydridic reserves of
the planet, to wit from the moment of disappearance of the internal core of
the Earth.
The concept of the primordial hydridic Earth, that is developed by
V.N.Larin (1980) represents highly perspective, since it is based on the
precise cosmochemistric laws and will be coordinated to the modern data on
physics of the core and mantle of the planet, simplifies the solution of the
problem of geomagnetism and cycles of development the planet. Most
important, that on the basis of one leading process of cyclic degasing
hydrogen at the warm up and decomposition of the hydridic core, it is enable
to coordinate all the wide spectrum of the global geological phenomena
(formation of oceans, geosynclines, platforms, epochs of tectono-magmatic
activities and processes of oregenesis, connected to them), and come closer to
the understanding of the reasons of evolution of the geodynamic regime
during entire geological history of the Earth, from the earliest stages to the
modern time. Especially, it is necessary to emphasize, that the hydride
hypothesis "forces to work " globe in all its volume - from the internal core
up to terrestrial crust. This realization opens grandiose prospects in its
practical application to research the past, present and predict the future of our
planet. The task of the new ХХI century will be the creation of any uniform
theory of evolution of the Earth, on the basis of which, the problems of
metallogeny and searches of mineral deposits will be decided.
The " Metallogenic map of the geodynamic systems of the pulsating-
expanding Earth " and the “Explanatory note", proposing to the attention of
the geologists, is the first attemption to the solution the problems of
metallogeny on the basis of hydridic concept of the Earth.
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