Abstract- Şeşetyan MSc.
A PROBABILISTIC ASSESSMENT OF TEH SEISMIC HAZARD IN THE CAUCASUS IN TERMS OF SPECTRAL VALUES
(Thesis Supervisor: Mustafa Erdik)
The study encompasses the development of seismic hazard maps for the Caucasus Region. The study area extends from East Anatolia to the Caspian Sea and from Northern Iran to the Greater Caucasus. The maps are the results obtained from analyses based on the historical earthquake data, geology, tectonics, fault activity and a rational source regionalization. The findings are represented as iso-acceleration contours of horizontal peak ground acceleration and spectral accelerations (for predetermined natural periods) having a probability of exceedence for various periods.
Aspects od seismicity and engineering judgments were considered for assembling seismicity data and decision upon the distribution of earthquakes in each zone. For the seismic source identifications tectonic maps, seismicity and geologic knowledge were used. Fault locations and earthquake epicenters were correlated and the regions of homogeneous seismicity were constructed. From the seismicity statistics of each zone, the annual number of earthquakes were calculated and adjusted annual rates were found. The results are given three different soil conditions. Ground motion attenuation relationships of Boore, Joyner & Fumal, Campbell,and Abrahamson & Silva were used.
The resulting maps show that Peak Ground Accelerations and Spectral Accelerations reach their maximum value near the Fault Anatolian Fault Zone, followed by the East Anatolian Fault Zone, the southwest coast of Caspian Sea, , the Sevan Lake region and the Upper Caucasus. The iso-acceleration maps can be used to determine the peak ground accelerations and the design earthquake spectra necessary for the design of the buildings in the region if more detailed site-specific studies are nıt available. The incorporation of neighboring regions in the study is a prominent development of the study.