EUROPEAN GEOSCIENCES UNION GENERAL ASSEMBLY 2014
Vienna, Austria, 27 April – 02 May 2014
DENSITY VARIABILITY - FUNDAMENTAL BASIS OF STRUCTURE
FORMATION AND TECTONIC-GEODYNAMIC EVOLUTION OF THE EARTH
Hatam Guliyev1, Ibrahim Guliyev1, Gurban Yetirmishli2
Geology Institute of Azerbaijan National Academy of Sciences1
Republican Seismic Survey Center of Azerbaijan National Academy of Sciences2
E-mail: hatamguliyev@gmail.com
DENSITY VARIABILITY - FUNDAMENTAL BASIS OF STRUCTURE FORMATION
AND TECTONIC-GEODYNAMIC EVOLUTION OF THE EARTH
Abstract
It was shown that there are some common geomechanical basis of processes of consolidation,
deconsolidation, phase transitions, formation of zones of small shear stiffness (waveguides), realization of
material and energetic mass flow in the internal structures of the Earth based on fundamental properties of
basic systems of equations of nonlinear mechanics of the deformed bodies, data and results of Green,
Ringwood, Liu’s known experimental studies.
Its instability for different geological media was shown studying the distribution of medium density
depending on deformation changes.
It was shown that distinguishing various forms of instability there is general deformation mechanism of
consolidation process of compressible medium according to which transfer to deconsolidation occurs at certain
stages due to specific change of equilibrium states.
Instability of deformation process contributes to emergence of geometric structures in composition of
geological medium which are favorable to form deconsolidation zones and zones of small shear stiffness.
Destruction by delamination at various depth of the Earth's interior can lead to formation of voids of
various scale. Various forms of instability can be realized in the process of further evolution in the vicinity of
these free surfaces, and voids can be filled by the loosened mass, i.e. deconsolidation process occurs under
compression conditions.
More hard bodies of local scale in the form of rod, strips, plates, cylindrical bodies, voids etc. can exist
at different depth of mantle. These bodies can lose the stability within compression conditions. Therefore, part
of their material and environment are loosened and deconsolidation process occurs again.
The above described cases significantly depends on the realized form of deformation. Unevenness of
deformation has a great value.
Partial melting and magma formation can occur in these deconsolidated zones depending on mineral
associations, petrochemical properties, thermobaric conditions and depth. This process becomes more feasible
in case, when water appears as a result of dehydration in the considered zones.
Some of these zones of deconsolidation can turn to focus of liquefied mass and give the beginning to mass
flow on various directions in further evolution.
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Problem statement
a)
b)
Diagram of the matter density distribution of the Earth on depth:
a) the existing notion b) the proposed notion
Distribution of the medium density depending on its arbitrary deformation (Hatam Guliyev,2007-2008).
1

4
*
2
3
 I 3 2 ; I 3  1  2 A1  2( A1  A2 )  (2 A3  3 A2 A1  A1 );
3

A1  1   2   3 ; A2  12   22   32 ; A3  13   23   33 .
* – current density;  – initial density;  – the main components of Green deformation tensor
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In case of homogeneous deformation:
1  0 ;  2  0 ;  3   0 ,
then
1
*
2
3 2
 1  A 0  B 0  C 0  ; A  2     ;

B  4     ;
C  8 .
Comprehensive deformation (      1)
3
*

 1  2 0  2

For elastic body under compression
3
*

 1  x  2 ;

21  2 
x
P.
E
Р – pressure;  – Poisson’s ratio; Е – elasticity modulus
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Influence of deformation non-uniformity
*

1
1; 0.01
1; 0.1
1; 0.5
1; 1.5
1; 2
12
10
8
6
4
2
0
0
Dependence
 * on

0
Lin-Gong Liu’s experimental results on phase transition of orthopyroxene (90% MgSiO3Al2O3).
Phase transitions of orthopyroxene  garnet; garnet  ilmenite; ilmenite  perovskite occur at a
relative change in volume, respectively – 7,8%; - 8,0% and – 6,9%.
*
,%

28
24.55
21
17.14
14
8.44
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Enstatit
Enstatite
Garnet
Ilmenit
Ilmenite
Perovskit
Perovskite
0
Dependence
*
on

2
0
2.64
4
5.34
6
7.69
8
 0 ,%
and sequence of phase transitions for orthopyroxene
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Instability of deformation process
Instability of deformation process is one of sources of inhomogeneity
Various possible variants
Diagram of half-space loading in the
vicinity of the cylindrical void
Dependence of critical pressures on the thin-walled parameter.
Peu . -
Pcr .
Euler’s critical load (uniaxial compression along axis of the cylinder);
- Critical value under comprehensive compression, when an external impact
on the cylindrical surface is given in the form of conservative loads.
x1

H
P
2h
0
x2
P
P
l
Instability in the structure
Subsurface instability
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Instability in contact zones of various media
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Some numerical results
*
in case of comprehensive deformation of the medium

in the presence of the cylindrical void in it
.
Critical values  0 and

-(0)*, %
-(0)*, %
 * 
  ,%
 
 *
*
 * 
  , %
 
0,2
14,72
5,82
14,16
27,55
16,38
24,96
68,71
20,40
64,78
232,48
81,37
182,16
0,3
10,36
4,87
9,32
20,35
12,15
15,36
41,85
16,63
36,26
119,04
51,86
73,42
0,4
5,82
1,98
4,54
12,15
5,82
7,14
20,39
6,25
15,35
51,86
20,40
26,00
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Alternative magmatic foci
As a result of the instability, walls of the reformed voids and
disturbances are "went-off" as in mines and the medium fills voids by
shattering. At the same time, in case of dehydration, water may also appear
here. It`s also necessary to take into account the fact that such zones are
transformed into natural "pumps". They attract the temperature of the
medium, accumulate along and partial melting starts at a relatively low
pressure. Various variants of magma formation can be implemented at various
depths.
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CONCLUSION
1. The new approach that allows studying processes of non-uniform
deformation under high pressures considering appropriate phase transitions
for various rocks was developed basing on non-linear theory of deformation
of the continuous medium.
2. It was shown that specific deformations that differ from processes of
comprehensive deformed homogeneous media occur due to inhomogeneity
of structural constructions of the Earth interior and a variety of impact
systems.
3. Consolidation processes can turn into deconsolidation process - a
density variation can occur with the growth of the Earth's depth. Voids,
zones of small shear stiffness (waveguides) can form due to the deformation
at various depths; foci of the diluted mass can form in these zones in
certain cases which can become a source of mass flow in further evolution.
THANK YOU FOR YOUR ATTENTION!
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