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and independent of one another. Their preferential positioning on the
continent-ocean margin defines a discontinuity in the mantle that penetrates
far into the planetary interior. The existence of a continental margin
discontinuity is, in fact, supported in geophysics (Toksoz & Anderson,
1966). By dividing the mantle into suboceanic and cubcontinental blocks,
the discontinuity comprises a network of important paths for the migration
of hydrogen from the Earth’s core. Where it conducts a strong flow of
hydrogen, the conjunction between continent and ocean, involving marginal
seas and island arcs, is said to be of Pacific type of active transital. Lacking
a strong hydrogen flow, the coast is described as Atlantic type of passive
transital (Larin, 1993).
The singularities of metallogeny of active transital are being reviewed
above at the performance of East - Asian and Australian-Pacific megabelts.
Here, it is necessary to add, that the oil-and-gas-bearing basins near the
coasts of Sakhalin, Indochina, Indonesia, Philippine, California and the bay
Cook on Alaska, are dated as the active transital, but on reserves they are
considerably yielded to oil-and-gas-bearing provinces on passive shelfs.
The significant feature of the active transitals is disposing them
basically to most ancient and mature on the planet Pacific Ocean, thus all of
them are separated from the ocean by deep-water trenches. The same
extended deep-water seismic active trenches are located immediately along
western beaches of Northern and Southern America. Thus, it is necessary to
point out, that metallogeny and magmatism of the West-American
continental belt, is practically, similar to metallogeny and magmatism of
East – Asian arc-island belt. Many geologists refer
marginal seas and island
arcs of active transitals to modern geosynclinal systems. Therefore, it is
possible to assume, that when there will be the inversion, folding and
orogeny of the East-Asian geosynclinal belt, the Asian continent will be
increased at the expense of the territory of the Pacific ocean, now restricted
by deep-water trenches, and to be turned into mountain-plait belt, similar to
West-American Cordilleras and Andes. In our opinion, the presence of the
deep-water seismic active trenches, confining active transital, testifies about
mature stage of geodynamic development of the Pacific Ocean, than it
explains especially rich mineralization in comparison with other, younger
oceans.
V.4. O c e a n s. Under оceanic geodynamic systems we understand
the bottom of the World Ocean behind exterior limits of the continental
decline, which includes the couch of oceans and mid-oceanic ridges, or
more specifically the oceanic platforms and georiftogenals. Underwater
oceanic platforms are named in the scientific literature as thalasso-cratons,
meaning under these tectonically stable areas of ocean bottom, undergoing
predominantly downward vertical movement and practically aseismic. They
occupy 193.8 million km
2
that makes about 38% of the surface of the
planet. Georiftogenals include mid-oceanic ridges and their slopes, forming
oceanic crust while moving apart. Together they generate the planetary belt
of linear elevations. Its communal extension is more than 70,000 km, which
occupy the area of 55.4 million km
2
or about 11 % of the entire surface of
54
the planet. Separate mid-oceanic ridges have stretch up to 10, 000 km
in length, with width of 1,000-4,000 km and height of 2-4 km. The axis of
ridges have in plan characteristic rectangular-cranked design, composed of
alternate lengthwise rifts sites and crosscut to them shift transformal faults.
The rifts and transformal sites of tallasids arise simultaneously
throughout at the expansion of the Earth and the breaking of the initial
megablock of the earth crust. These zones are reasonably seismic active
with infrequent epicenters of strong earthquakes. There is a permanent
reproduction of oceanic crust in the axises of georiftogenal, accumulating at
the spreading moving in counter parts of the boundary megablock, where
the power of oceanic crust reaches 6-8 km. The extension of the bottom of
oceans in axles parts of these ridges takes place in horizontal direction with
the speed of 1-12 sm/year during the Pliocene and Holocene (Leontyev,
1982
). The relative dispersion of the squares of continental and oceanic
crust demonstrates that for the score of formation the oceans, it is possible
to suppose the increase of the surface of the Earth approximately in 2.5
times and the decrease the gravity to 1g for the last geodynamic cycle of
development of the planet by duration about 200 Ma (Larin, 1980).
According to our model, the ocean was a simple and, most likely, a
shallow, marine basin in the first (juvenile) stage of basin evolution. This
period lasted until continuity of the asthenosphere was disrupted. As soon
as that happened, oceanic structure changed, and there appeared along its
axis a median uplift, as if reflecting the pattern of the newly forming ultra-
deep diapirs flanked by the young silicate buffer, and rising nearer and
nearer to the surface of the planet. While in the “youth” stage the mid-
oceanic ridge was produced by the forcing out of old mantle blocks through
the overlying cover. A piston-like action by deep sub-oceanic diapirs is
envisioned. At later stages the newly formed silicate buffer comes to the
surface, and the “mature” stage of oceanic evolution begins. No further
structural change is envisioned, but dimensional increases, owing to
spreading transverse to the ridge, and growth of the extension component in
transform faults are possible. The interpreted deep structure of the ocean
corresponds to the mature stage of its evolution (Larin, 1980).
In the light of hydridic conception, the deep-seated processes that
brought about formation and evolution of oceans can be traced to origins in
the extension zones at the base of the mantle and above the planetary
decompaction front, through which plastic matter in the form of diapirs
ascends to the upper geospheres from the shell that envelops the Earth’s
core. This plastic substance consists of metal made liquid by protonic
hydrogen. The first pulse of tectonism presaging chimneys of weakness
should have occurred at the base of the mantle at the interface with the
decompaction front. Form there is should have spread upward and
simultaneously filled with substances elevated from the deepest layer of the
mantle. This layer may contain residual hydrogen in the diffuse form of a
proton gas, its concentration already insufficient to compact metals but
perhaps still sufficient to cause a sharp drop in viscosity, and thusly to
provide effective plastic flow. The existence of a plastic layer at the base of