Estimation of Peak Ground Acceleration for Delhi Region using Finsim, a Finite Fault Simulation Technique

Abstract

The Delhi is situated in highly earthquake prone belt (IS: 1893-2002) near the tectonically active Himalayan region occupying an area of 1485 sq.km. An important problem in earthquake engineering is the prediction of ground motions from the future large earthquakes. Seismological input that describes the amplitude, frequency content and duration of the expected motions are required to assess the seismic performance of the structures. Several empirical relationships are available in the literature for the estimation of these ground motions. In this study, the stochastic finite fault simulation technique which implements the concept of fault discretization wherein the sub events are represented as stochastic point sources is used. The detailed description of the method is given by Beresnev and Atkinson (1997, 1998). Based on the historical seismic source data, using the FINSIM program the Peak Ground Acceleration (at bedrock level) map of the Delhi region is prepared. This map can be used further as input for microzonation of ground motion at the surface by incorporating the local soil conditions in the Delhi region.