1. Implications of Site Effects and Attenuation Properties for Estimation of Earthquake Source Characteristics in Kinnaur Himalaya, India.
- Author
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Kumari, Richa, Kumar, Parveen, Kumar, Naresh, and Sandeep
- Subjects
SEISMOGRAMS ,EARTHQUAKES ,QUALITY factor ,SHEAR waves ,SEISMOMETERS ,EARTHQUAKE magnitude - Abstract
Site and path effects are always required to isolate the source term from a recorded seismograph for the estimation of source characteristics. In this paper, the site and path effects are assessed in terms of site amplification and anelastic attenuation (quality factor), respectively, to obtain an isolated source term for the estimation of earthquake source parameters in the Kinnaur Himalaya. These terms are then applied to calculate the source parameters of 75 local earthquakes in the range 1.5 ≤ moment magnitude (M
w ) ≤ 3.6 recorded in the Kinnaur region. The scaling relations of earthquake source parameters are also established for this region. The site amplification curves and S-wave quality factor Qs (f) are determined and further utilized to correct the Fourier spectrum of earthquake records. The obtained source spectrum corrected for these two terms is compared with the theoretical source spectrum based on the Brune (J Geophys Res 75:4997–5009, 1970) source model. The root-mean-square error (RMSE) between the observed and theoretical spectrum is formulated by implementing iterative forward modeling. The obtained range of source parameters of 75 events reveals ranges of 2.73 × 1011 –3.44 × 1014 N-m for seismic moment, 0.03–13 bar for stress drop, 0.3–0.9 km for source radius, and 5.64 × 1002 –1.19 × 1008 J for radiated energy. [ABSTRACT FROM AUTHOR]- Published
- 2021
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