43
Earth and degassing protonal hydrogen along depressed flatness zones in
mantle and in the earth’s crust. The plutonic processes leading to formation
of oceans, in the light of hydridic concept of the Earth, added up to location
zones of extension on the base of mantle. Hereof the diapirs of plastic
metals, «liquefaction» by protonic hydrogen, are pressed out through mantle
to the upper geospheres. The new silicate crust of oceanic type is shaped on
both sides of them, starting from central riftogenal zone. In reference to the
decompress of the exterior core and mantle, the midlle gravity of the Earth
in Paleozoic was diminished up to 2.0 g, and the radius was 1.6 times less
than the modern (Larin, 1980).
In late Riphean – Vend all types of geodynamic systems and regimes
have developed. The new continents are isolated; the orogenic belts, mainly
in Gondwana, have formed. The disparity of geodynamic regimes of
southern and northern supercontinents can be clearly traced. In Gondwana
the eocratons are consolidated and soldered under the influence of
panafrican orogeny. On the contrary Lavrasia is disintegrated at the expense
of the origination a new riftogenal belts and oceans. The large platforms
such African and East-Siberian were shaped, on which intensive
sedimentation in the syneclises and avlacogenes took place. The trapp
syneclises and intracratonal geosynclinal’s troughs of ensialic and ensimatic
types were formed. The marginal miogeosynclinals originated on the
peripheries of the continents and eugeosynclinals on the oceanic crust
formed in South-East Asia. The active edges of Ands type developed on
continents in Vend. It is remarkable, that the regimes of tectono-magmatic
activating of Protodiva type were widely exhibited on supercontinent
Gondwana, while in Lavrasia they are almost absent (Khain, Seslavinskiy,
1991).
Wide development on the peripheries of continents the marginal
vulcanogenic belts, island arcs and ophiolites, testifies to the disintegration
of Pangea II and the formation oceans on the Earth in late Riphean-middle
Paleozoic. At the same time there were isolated platform areas and
geosynclinal’s belts, bordering or sectioning them. The North American,
East Europe, Siberian, Chine-Korean platforms were generated in the
Northern hemisphere. On the supercontinent Gondwana the following
platforms were formed: African, South American, East Antarctic,
Australian and Hindustan.
The mobile geosynclinal’s belts of Caledonian and Hertzinian
tectonogenic stages in the northern hemisphere were represented by
Appalachian, East Greenland, Innuit, Britan-Scandinavian, Taymyr, Ural-
Ochotsk, Gobi-Khingan systems, and also West- and East-Pacific belts. On
the continent Gondwana there was some number of narrow geosynclines in
late Riphean, for example, Rybaro-Damar, Mauritanian, West-Kongo,
Libya-Nyger, Mozambique, Cape Town. Along the mobile Paleozoic belt
of Prototetis ocean there were Аrmorycan, West-European, Каvkaz-
Pamyrean, Byrmean geosynclinals systems have formed. West-Brazilian
and Argentinean Paleozoic geosynclines had existed in Southern America.
44
Beside them Trans-Antarctic and East-Australian geosynclines belts had
formed.
The metallogeny of late Riphean – Paleozoic cycle of the development
of the Earth had differed by very major variety of genetic types and specific
mineral deposits, since they are related to different geodynamic systems,
cardinally discrepant as for their geological conditions of formation, starting
from vulcano-sedimentary plate covers of platforms up to geosynclinal-
folded systems and finishing by oceanic basins.
The metallogeny of platform’s geodynamic system we shall consider on
the example of the Russian platform. It holds the leading position
according to reserves and mining in Russia of such mineral resources as
iron, phosphorus, potash and halite salt, sulfur, phlogopite, vermyculite,
titan, manganese, mercury, bauxites, nepheline, diamonds, black and brown
coals, fuel shales, gas and oil. In their crystalline foundation, the giant
deposits of iron, nickel and copper, muscovite and graphite have been
discovered. Some particular types of mineral resources are typical for each
stage of tectono-sedimentary development of this platform. So, the
sedimentary deposits of iron, manganese, titanium, and phosphorites and
also placers of gold and diamonds are typical to the transgressive stage. The
fuel schist with the impurity of iron, lead, zinc, barite, fluorite and
phosphorites are peculiar for inundation stage of stability depression. The
formation of giant deposits of potash and halite, iron and hard coal are
typical for the regressive stage. The emersive stage of elevation of the
platform and epochs of chemical weathering are specified by deposits of
iron, bauxites, sulfur, vermiculite, black and brown coals, placers of titanic
minerals and zircon. The periods of tectono-magmatic activating are
characteristic for the emersive stage of elevation platform, with which the
deposits of titanemagnetite, nickel and copper (trapp formation); magnetite,
apatite, nepheline and rare-earth elements (nepheline-syenite formation),
phlogopite and vermiculite (carbonatite formation); diamond (kimberlitic
formation) are connected (Staritskiy et.al., 1989).
The Siberian platform differs by the largest deposits of Vend, middle
Paleozoic and early Mesozoic epochs of tectono-magmatic activating. They
are represented by diamond’s kimberlite pipes of Yakut; copper-nickel with
platinum and gold ores of Norilsk trapps; phlogopite–apatite-magnetite
deposits of Коtuy-Maymechin carbonatite province; niobium-yttrium-
scandium terra-rare of giant deposit of Tomtor carbonatite; iron-ore
scarnoides of Angaro-Ilim province and the hard coals of Tunguska
province (Krutoyarskiy, 1958; Malich et. al., 1997; Frolov et.al., 2003).
On the African platform richest stratiformal deposits of copper, cobalt
and uranium with the impurity of nickel and infrequent metals are
connected to Vend- early Cambrian sandstones and dolomitic shales of
Katanga formation in Zair, Zambia, Congo and Namibia. The copper-zinc-
lead deposit Tzumeb rich of germanium are known in dolomites of the
system Otavy. Similar of the genesis and age the giant deposits of zinc-lead
ores with the impurity of germanium, cadmium, platinum and vanadium are
available on the Brazilian platform (Jenuaria and Vazanti).
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