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Earthquake ground motion is affected from local soil conditions, geological structures as well as earthquake source properties. The amplitude and frequency content of the strong ground motion can be changed by local site effects. Local site conditions such as seismic bedrock depth, bedrock slope of the edge, geometry and characteristics of soil layers and topographical irregularities are the most important factors affecting soil amplification. One dimensional (1D) equivalent linear dynamic analysis method is the simplest approach to investigate local site effects. 1D approach becomes valid especially for the sites far from edges or in shallow and wide valley models. In narrow and deep basins, body waves transform into surface waves especially at the edges during earthquakes and two dimensional (2D) resonance modes occur, the frequency content and amplitude of strong ground motion may vary with the distance from basin edge to its center. In this study, to investigate the effects of basin edge on the variation of surface motion under different strong ground motion acceleration records, one and two dimensional dynamic analyses were performed by using the Dinar basin edge model and the results were compared. The variations of the spectral acceleration ratios (2D/1D) were evaluated for the different points on the ground surface with the changing distance from the valley edges. A relationship between the results of one and two dimensional dynamic analyses wasestablished. Shear wave velocity profile and bedrock depth in Dinar were obtained from microtremor array measurements.