SOURCE PARAMETER ESTIMATION FOR KINNAUR REGION

Abstract

The scope of this work involved the analysis and estimation of source parameters for a dataset from two seismic networks namely Wadia Institute of Hirnalyan Geology (WIHG) and National Seismic Network (NSN), which included a total of 152 local events recorded for 2 months in year 2008 and 3 months in 2009. The dataset consisted of earthquakes that occurred primarily in the Kinnaur region of Himachal Pradesh, India. The source parameters estimated are Stress drop, Corner Frequency, Source Radius, Local Magnitude and Moment Magnitude. S-phase spectra from the events was modelled as per the Brune model to arrive at the results. The results obtained after locating events and calculating source parameters and generating reltionships between them, showed that the results followed the standard observations in case of variation of Local Magnitude with Moment Magnitude. Corner frequency variations with the magnitudes also conform to the established results but vary in the degree conformity. Of the relationships that deviated from the norm of source parameter inter-relationships include the variation stress drop with both magnitudes and the fact that moment magnitudes have lower value that local magnitudes. Some results however were too scattered for a decent relationship to be calculated