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 May, 2013 Baku, Azerbaijan Fuad Aliyev 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 Seismology Database :  NEIC USGS – National Earthquake Information Center of US Geology Survey US Geology Survey  IRIS –  IRIS – Incorporated Research Institutions for Seismology  CTBTO – Comprehensive Nuclear-Test-Ban Treaty Org.  RCSS ANAS – Seismology Survey Center, Azerbaijan  ISC – International Seismological Centre Seismicity of the territory of a republic has been analyzed on the basis of the earthquakes’ catalogue

 Unified catalogue of earthquakes for  Totally 960 seismic events.  Representation, М≥4 for  Representation, М≥3 for Seismicity Seismology Database :

Map of seismicity with М≥3 for 427 – 2010

Map of Strong earthquakes occurred in Azerbaijan historically

Strong earthquakes occurred in Azerbaijan historically YearMonthDayFiLaHMRegion 42740,546,512,06,7Ganja ,6045, ,346,223,07,7Ganja ,447,020,06,3Ganja ,948,220,07,0Shemakha ,048,06, ,748,45,7Shemakha ,550,00,04,7Mashtaga ,748,512,06,1Shemakha ,246,830,06,3Zurnabad ,748,75,0Shemakha ,648,77,06,0Shemakha ,247,611,06,5Iran ,748,518,06,9Shemakha

Map of Strong earthquakes occurred in Azerbaijan ( )

Map of maximum intensities

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

Map of Maximum Earthquake intensities for the period

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.

Map of Maximum Earthquake intensities for the period

Earthquakes distribution within 1º area for

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

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.

- 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