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Because the instrumental records of Turkey are far from being satisfactory for modeling the seismic hazard using the probabilistic approach, an attempt was made in this study to accomplish it through the deterministic way. In this regard, all active faults of Turkey, small and large, were evaluated together to obtain major fault systems. Then, the procedure suggested by Wells and Coppersmith [Bull. Seismol. Soc. Am. 4 (1994) 975] applied to those faults to obtain the maximum magnitude earthquake that they can generate. To do this, it was assumed that 1/3 of the total fault length would rupture to yield the maximum earthquake. Following that, seven different attenuation relationships of the strong ground motion were utilized to calculate the maximum horizontal ground accelerations for the whole Turkey at 0.2° intervals using the computer model TUMDES written in BASIC programming language.The computed peak ground acceleration (pga) values were contoured and the iso-acceleration map based on Sadigh et al. [Seismol. Res. Lett. 1 (1997) 180] relationship was selected as the new seismic hazard map of Turkey on which the seismic zonations were determined as following: pga>0.3 g Zone 1; 0.3 g

Recent developments in the neotectonic framework of Turkey introduced new tectonic elements necessitating the reconstruction of Turkey''s seismic hazard map. In this regard, 14 seismic source zones were delineated. Maximum earthquake magnitudes for each seismic zones were determined using the fault rupture length approximation. Regression coefficients of the earthquake magnitude–frequency relationships for the seismic zones were compiled mostly from earlier works. Along with these data, a strong ground motion attenuation relationship developed by Joyner and Boore [Joyner, W.B., Boore, D.M., 1988. Measurement, characterization, and prediction of strong ground motion. Earthquake Engineering and Soil Dynamics, 2. Recent Advances Ground Motion Evaluation, pp. 43–102.] was utilized to model the seismic hazard for Turkey using the probabilistic approach. For the modeling, the “earthquake location uncertainty” concept was employed. A grid of 5106 points with 0.2° intervals was constituted for the area encompassed by the 25–46°E longitudes and 35–43°N latitudes. For the return periods of 100 and 475 years, the peak horizontal ground acceleration (pga) in bedrock was computed for each grid point. Isoacceleration maps for the return periods of 100 and 475 years were constructed by contouring the pga values at each node. [Copyright &y& Elsevier]