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New Challenges in the European Area:
Young Scientist’s 1st International Baku Forum
New Challenges in the European Area:
Young Scientist’s 1st International Baku Forum
Relation between seismicity and tectonic structures
within Azerbaijan part of the Greater Caucasus.
Fuad Aliyev
[email protected]
Institute of Geology, ANAS
21 - 25 May, 2013
Baku, Azerbaijan
Objectives
• Spatial distribution peculiarities of earthquakes
• Studying of relationship between recent tectonic
movements with seismicity
• Revelation of active parts of tectonic faults
Allocation of accretionary prism within Caucasus structure
The Greater Caucasus has formed during last stage of the tectogenesis in a
geodynamic condition of the lateral compression, peculiar to the zone of pseudosubduction interaction between Northern and Southern Caucasian continental
microplates.
Collision of Arabian plate with Eurasian plate
Azerbaijan is located within active collision zone of Arabian and
Eurasian plates. Actually observing continental collision
characterized by the movement of Arabian plate to North direction
and displacement of Anatolian plate to western, and Iranian plate to
eastern direction and compression of the Great Caucasus.
Earthquakes that occur in
Azerbaijan territory give us
information about dynamics of
deep faults, structure of earth’s
crust, allow tracing active zones
of the faults, and can reveal
peculiarities of spatial distribution
of strong earthquakes.

Plate tectonic reconstructions provide broad
constraints on the timing of the initial collision of
the Arabian Plate with Eurasia, and indicate that
the rate of northward motion of Arabia relative to
Eurasia has remained more or less constant at
about 20 mm/yr since collision began.
 Earthquakes that occur in Azerbaijan territory give
us information about dynamics of deep faults,
structure of earth’s crust, allow tracing active
zones of the faults, and can reveal peculiarities of
spatial distribution of strong earthquakes.
Seismicity
Seismology Database :
Seismicity of the territory of a republic has been analyzed on the basis of
the earthquakes’ catalogue

NEIC USGS – National Earthquake Information Center of
US Geology Survey
 IRIS – Incorporated Research Institutions for Seismology
 ISC – International Seismological Centre

CTBTO – Comprehensive Nuclear-Test-Ban Treaty Org.

RCSS ANAS – Seismology Survey Center, Azerbaijan
Seismicity
Seismology Database :

Unified catalogue of earthquakes for 427-2010

Totally 960 seismic events .

Representation, М≥4 for 427-1902

Representation, М≥3 for 1903-2010
Map of seismicity with М≥3 for 427 – 2010
Map of Strong earthquakes occurred in Azerbaijan historically
Strong earthquakes occurred in Azerbaijan historically
Year
Month
Day
427
21
Fi
La
H
M
Region
40,5
46,5
12,0
6,7
Ganja
39,60
45,40
12
7.0
735
7
1139
9
40,3
46,2
23,0
7,7
Ganja
1235
10
40,4
47,0
20,0
6,3
Ganja
1667
40,9
48,2
20,0
7,0
Shemakha
1668
41,0
48,0
6,8
1828
40,7
48,4
5,7
Shemakha
1842
1
2
40,5
50,0
0,0
4,7
Mashtaga
1859
6
12
40,7
48,5
12,0
6,1
Shemakha
1868
3
21
40,2
46,8
30,0
6,3
Zurnabad
40,7
48,7
5,0
Shemakha
1869
1872
1
29
40,6
48,7
7,0
6,0
Shemakha
1875
3
22
39,2
47,6
11,0
6,5
Iran
1902
2
16
40,7
48,5
18,0
6,9
Shemakha
Map of Strong earthquakes occurred in Azerbaijan (427-2010)
Map of maximum intensities
42
9
8.5
41
8
7.5
7
40
6.5
6
5.5
39
5
4.5
45
46
47
48
49
50
51
52
Map of maximum intensity distribution
One of the most important aspects of seismic hazard estimation is the
calculation of earthquake occurrence possibility with different intensity
values in any place without indication of time, whenever any seismic event
may take place (Riznichenko Yu. V., 1979). Such analyzes and calculations for
Azerbaijan territory have been conducted before (Kadirov F.A., et al., 2008),
using data from instrumental registered earthquakes. So far as the data about
intensities for pre-instrumental earthquakes haven’t been used before, we
have included those too for our calculations.
For the plotting of a map of maximal intensity, the area of
study has been equally gridded by 20x20 km cells of 0.5
degrees . By the use of combined catalogues, for each
cell, the intensity value from each earthquake has been
calculated using the following equation
I 1.4M  3.5lg(R)  3.5
R  h x
2
2
Riznichenko Yu. V. Seismic
shakability of USRR
territory.1979
42
9
8.5
41
8
7.5
7
40
6.5
6
5.5
39
5
4.5
45
46
47
48
49
50
51
52
Map of Maximum Earthquake intensities for the period 427-2010
42
9
8.5
41
8
7.5
7
40
6.5
6
5.5
39
5
4.5
45
46
47
48
49
50
51
52
From the map of maximum intensities of earthquakes we can observe that
the zones subjected to strong earthquakes distributed irregularly. The
isolines of high intensity of earthquakes comply with the regional deep
faults. This conformity can be observed in collision zone along Main
Caucasus Thrust, located on the Southern slope of the Greater Caucasus
in Shamakhy-Ismailli seismic zone, and then alongside the fault, in a
Caspian Sea basin southward from Absheron peninsula. The same
situation is also observed in a Lesser Caucasus along the KizilagajVandam, Kura and Fore-Lesser Caucasus faults.
42
9
M-K
8.5
41
8
7.5
АГД
ГКН
40
КУР
7
К-В
ПМК
6.5
6
НАХ
5.5
39
5
4.5
45
46
47
48
49
50
51
52
Map of Maximum Earthquake intensities for the period 427-2009
Earthquakes distribution within 1º area for 1902-2010
Collision of Arabian plate with Eurasian plate
GPS horizontal motion rates for Azerbaijan and adjacent areas

Cureently running GPS
network of Azerbaijan,
establuished by the
Institute of Geology,
ANAS in cooperation
with MIT in different parts
of a pepublic, and two
continious real-time GPS
stations.
Distribution of Seismic Energy released from zones
Energy (J)
5E+15
4E+15
3E+15
2E+15
1E+15
0
I
II
III
IV
Zones
Map of Earthquake foci zones of the North-West Azerbaijan (I –
Zagatala, May, 2012, II – Balaken, October, 2012, III – Sheki, May, 2012
This fact of recent seismic activity is particularly proved by earthquakes which
have taken place between May and December, 2012 in Zagatala, Sheki and Balakan.
Geological-geophysical section through focal zone of Zagatala
earthquakes
Focal zone of the earthquake is confined to a complex intersection knot of
different strike faults, and is located in Pre-Jurassic basement. The very seismic
event is mainly related with activity of Zagatala fault with northwestern strike
which caused activation of connected dislocations.
Geological-geophysical section through focal zone of Balakan
earthquakes
Focal zone of the earthquake is confined to a complex intersection knot
of the faults with various strike, and is located in the upper part of
Pre-Jurassic basement.
Fig.19. Geological-geophysical section through focal zone of
Sheki earthquakes
Earthquake's focal zone is situated in the upper part of Pre-Jurassic basement.
Seismic event is connected with activity of subvertical faults with northeastern dir.
Conclusions.
- According to the distribution of GPS rates along MCT, there exist 4 zones with
different values of tectonic stress.
- From the map of maximum intensities of earthquakes we can observe that the
zones subjected to strong earthquakes distributed irregularly.
- At the junction of MCT with K-V fault zone, located in Shamakhy region we
observe earthquakes with maximum intensities.
- Hypocenters of major seismic events (М = 4,5-5,7) and absolute majority of
aftershocks are confined to a pre-Jurassic basement's surface or its' depths of up
to 20 km (from 2012 events);
- In general the seismic activity of a mentioned period is explained by
accumulation of lateral compression stresses and their later discharge in an
underthrust articulation line of Middle Kur and Vandam tectonic zones along
Ganikh-Ayrichay-Alat deep overthrust.
Thanks for Attention !!!
Fuad Aliyev