Attenuation correlation is a key component in estimating ground motion parameters for a site. There are two methods available for developing attenuation relation. First one is regression from strong motion data base and the second one is from simulation. First method is suitable for inter plate regions such as Western North America (WNA) where seismicity rates are such that sufficient strong ground motion is available for regression analysis. Second method is suitable for intra plate regions such as Eastern North America (ENA) where seismicity rates are less. Vizag site is in Peninsular India which is an intra plate region where strong motion data is scarce and not representative of existing hazard. Hence, the second approach is suitable for development of attenuation correlation for Vizag site. The first step in the method involves ground motion simulations for a range of magnitudes and distances as well as expected parameter values. Finite fault stochastic simulation method is used for this purpose. In the second step a suitable functional form is selected for the regression equation and in the final step, regression analysis is carried out to determine coefficients for predictions. A frequency dependent attenuation relation is developed from the simulation data base for Vizag site. Earthquake records of intra plate regions are considered for validation purpose. The present paper describes the methodology and results of these simulations.

Keywords: Attenuation correlation, Finite fault stochastic simulation, Response spectrum.