22
Table 5
Hierarchy of the geodynamic systems (Smyslov, 1983)
Types of
Geodynamic
Systems
Polygonal
Linear
Global
Continental plates
and their segments
( N. American plate )
Oceanic plates
and their segments
( W. Pacific plate )
Mid oceanic ridges,
georiftogenals
( Atlantic MOR )
Trans-
regional
Continental
megacratons
(Russian
platform)
Oceanic
megacratons
(West Pacific)
Folder areas
(Kazakhstan-
Mongolian)
Marginal deep-see valleys
(Okhotsk-Japanese)
Volcanogenic belts
(Hawaiin islands)
Island arcs
(Japanese)
Regional
Cratons
(Ukrainian shield)
Median massives
(Kolyma massive)
Deep uncompencated
depression
(Sub-Kaspian)
Continental rifts
(Baikal rift)
Sutural zones
of spreading
(Ural)
Transformic faults
(Clarinton)
Local
Synclines
(Moscowian)
Anteclises
(Volga-Uralian)
Intermountain
depression
Avlacogenes
(Uachita)
Oceanic ridges
(East Pacific)
Plutonic faults
23
The geodynamic systems of the Earth, concerning their thermodynamic
regimes, were subdivided in three types: have been stabilized ( had cooled),
are still stabilizing (are cooling) and active (warming up).
Three following types of lithosphere have been distinguished that appear in
various stages of the development of the Earth, and which are typical for
different geodynamic systems with consideration of duration and evolution of
the substance and energy of the mantle-crust blocks on the continents and
oceans:
1. ancient (Archean-Proterozoic) consolidated lithosphere and sharp
differentiated continental earth’s crust of salic type with thickness 35-60 km;
2. ripen (Riphean-Paleozoic ) consolidated lithosphere with differentiated
earth’s crust of salic-femic type with powerful about 20-35 km;
3. young (Mesozoic – Cenozoic) generating lithosphere of oceanic
femic type, that began forming in Mesozoic and continued up to the present
time along the georiftogenal, with earth’s femic crust of thickness near 6-10
km. The Sub-Caspian uncompensated depression is the example that before
regards to the cover of Russian platform. Such type of depression is probably
antipodes of median massives that have advantage to elevation. Peculiar
feature of all types of polygon systems is the dominance of the crust material
differentiation at the mantle energetic and dynamic supply, determining long-
lived stable and directional elevation of structures or their depression.
Essentially another processes and activing forces are peculiar for linear
geodynamic systems, distinguished in independent groups, for which are
characteristically extension (rifts, pull-aparts), more seldom compression
(pulls) or combined moves (compression – extension), conventional by
horizontal movements of geological bodies. However, in these structures at the
dominant role of vertical moves of matter in the next stages are fixed vertical
movements. For example, the downing in central parts of zones pull-apart
(rifts) is combined with powerful accumulation of sediments and / or intrusion
of mantle magmatic matter ( Smyslov, 1998 ).
The linear geodynamic systems are usually disposed at the center or on
the periphery of polygon mosaic structure, forming sutured zones of different
scale. For example, the global spreading georiftgenalic zones are found in the
center of oceanic depressions with the identical type of lithosphere. The
transregional Benioff zones, the island arcs and the volcanic belts are disposed
on boundaries of mantle-crust blocks. The regional and local continental rifts,
plutonic faults, avlakogenes are usually located at the periphery of polygon
geodynamic systems. The sutured zones of pulling apart are widely developed
among the linear systems, along which the intrusions of mantle matter, such as
hyperbasits, basic vulcanites, protrusions of ophiolites are impregnated. In
some cases the rift’s depressions take place the powerful sedimentation and
with the subsequent folding and forming of riftogenal-folded zones. As a
whole, the linear geodynamic systems have a major vertical extension, and
they swish the Earth’s crust on all its power and go away with their roots to
considerable depth (100-200 km) in the upper mantle. Such systems on the
features of differentiating of the matter and the nature of energetic and
geodynamic supply can be regarded as mantle-crust.
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