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

21 - 25 May, 2013 Baku, Azerbaijan

Fuad Aliyev

fuad_al@yahoo.com Institute of Geology, ANAS

Relation between seismicity and tectonic structures within Azerbaijan part of the Greater Caucasus.

Objectives

• Studying of relationship between recent tectonic movements with seismicity

• Revelation of active parts of tectonic faults

• Spatial distribution peculiarities of earthquakes

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 pseudo-subduction 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 Seismicity Seismology DatabaseSeismology Database : :

NEIC USGSNEIC USGS – National Earthquake Information Center of – National Earthquake Information Center of US Geology SurveyUS Geology Survey

IRISIRIS – – Incorporated Research Institutions for Seismology

CTBTOCTBTO – – Comprehensive Nuclear-Test-Ban Treaty OrgComprehensive Nuclear-Test-Ban Treaty Org..

RCSS ANASRCSS ANAS – Seismology Survey Center, Azerbaijan – Seismology Survey Center, Azerbaijan

ISCISC – – InternationalInternational Seismological CentreSeismological Centre

Seismicity of the territory of a republic has been analyzed on the basis of the earthquakes’ catalogue

Unified catalogue of earthquakes for Unified catalogue of earthquakes for 427-20427-201010

Totally Totally 960 960 seismic events seismic events ..

RepresentationRepresentation, М, М≥4 ≥4 for for 427-1902427-1902

RepresentationRepresentation, М, М≥3 ≥3 forfor 1903-20 1903-201010

Seismicity Seismicity

Seismology DatabaseSeismology Database : :

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 Fi La H M Region

427 40,5 46,5 12,0 6,7 Ganja

735 7 2121 39,60 45,40 12 7.0

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

1869 40,7 48,7 5,0 Shemakha

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

4 5 4 6 4 7 4 8 4 9 5 0 5 1 5 2

3 9

4 0

4 1

4 2

4 . 5

5

5 . 5

6

6 . 5

7

7 . 5

8

8 . 5

9

22

5.3)(5.34.1

xhR

RlgMI

Riznichenko Yu. V. Seismic shakability of USRR territory.1979

Map of maximum intensity distributionOne 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

4 5 4 6 4 7 4 8 4 9 5 0 5 1 5 2

3 9

4 0

4 1

4 2

4 . 5

5

5 . 5

6

6 . 5

7

7 . 5

8

8 . 5

9

Map of Maximum Earthquake intensities for the period 427-2010

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 Kizilagaj-Vandam, Kura and Fore-Lesser Caucasus faults.

4 5 4 6 4 7 4 8 4 9 5 0 5 1 5 2

3 9

4 0

4 1

4 2

4 . 5

5

5 . 5

6

6 . 5

7

7 . 5

8

8 . 5

9

45 46 47 48 49 50 51 52

39

40

41

42

4.5

5

5.5

6

6.5

7

7.5

8

8.5

9M -K

ГКНК-В

КУРП М К

НАХ

АГД

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

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.

GPS horizontal motion rates for Azerbaijan and adjacent areas

Distribution of Seismic Energy released from zones

0

1E+15

2E+15

3E+15

4E+15

5E+15

I II III IV Zones

Energy (J)

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 Geological-geophysical section through focal zone of Zagatala earthquakes 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 Geological-geophysical section through focal zone of Balakan earthquakesearthquakes

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 Fig.19. Geological-geophysical section through focal zone of Sheki earthquakesSheki 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.

- 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.

Conclusions.

Thanks for Attention !!!Fuad Aliyev