Deterministic Seismic Hazard Assessment by revisiting 1991 Uttarkashi and 1999 Chamoli Earthquake for Uttarakhand, India
- 1Indian Institute of Technology Roorkee, Department of Earthquake Engineering, India (yaggeshsharma24@gmail.com)
- 2Water Engineering and Management, Asian Institute of Technology, Pathumthani, Thailand -12120
Deterministic Seismic Hazard Assessment is a quantitative site-specific evaluation of ground response for a particular region. Destructive effects caused due to occurrence of natural seismic hazards can be minimized by accounting mindful mitigation measures. One of the fundamental phases in risk assessment is the précised determination of the risk over a certain period. Considering the earthquake rupture model and a couple of defined region-specific ground motion models as input, earthquake scenarios to determine peak ground acceleration (PGA) and spectral periods (SA) are examined. In the present study, the Topographic slope as a proxy for shear wave velocity in upper soil of 30-meter (Vs30) estimation is assessed for rapid prediction and first-order studies. Further, two distinct major earthquake scenarios, the 1991 Uttarkashi and 1999 Chamoli earthquakes are revisited to estimate the distribution of PGA and SA at 0.2 sec and 1 sec for the area of interest. Thus, obtained results for Uttarakhand are presented in terms of Vs30, PGA, 0.2 sec, and 1-sec spectral values respectively.
Keywords: Deterministic seismic hazard, Vs30, 1991 Uttarkashi, 1999 Chamoli, scenario earthquakes, PGA, SA.
How to cite: Sharma, Y., Srivastava, M., Sharma, P., and Kumar, D.: Deterministic Seismic Hazard Assessment by revisiting 1991 Uttarkashi and 1999 Chamoli Earthquake for Uttarakhand, India, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-11563, https://doi.org/10.5194/egusphere-egu23-11563, 2023.