PEAK GROUND HORIZONTAL ACCELERATION ATTENUATION RELATIONSHIP FOR LOW MAGNITUDES AT SHORT DISTANCES IN SOUTH INDIAN REGION

摘要

Attenuation relationships for peak horizontal ground acceleration for short distances and low magnitudes have been developed for Kolar Gold Fields mines region in South India. The distance range upto 5 km and the magnitudes ranging between 0 and 3 have been used for the development of the attenuation relationship. Two steps multiple regressions have been made by analyzing the decay of individual magnitude classes with distance using it with the whole data set. The model used in the present study is Where y is the peak ground horizontal acceleration, X is hypocentral distance and m is local attenuation characteristics of the ground motion at shorter distances and low magnitudes have been discussed. The comparison of strong ground motion at similar distances using relationships developed from higher magnitudes reveals the difference in the observed peak ground horizontal accelerations with respect to the strain levels involved in the generation of the respective earthquakes.