Site Characterization, Seismic Hazard in Kashmir Himalaya to Northeast India: 1D/2D/3D Modeling, Microzonation and Damage Studies

Indian subcontinent, marked by its intricate seismotectonic settings stands out as the most active region in the globe. This study conducts a firm rock-compliant probabilistic seismic hazard assessment considering both tectonic and polygonal sources in 0 km- 25 km, 25 km-70 km, 70 km-180 km and 180 km-300 km depth ranges, next generation attenuation models through a logic tree framework across the tectonic ensemble from Kashmir Himalaya to Northeast India encompassing six seismogenic tectonic provinces classifying the ensemble in the 'moderate' to 'severe' hazard regime, highlighting the need for a site-specific surface-consistent investigation that shear-wave velocity characterizes the Ensemble into site classes and estimates surface-consistent probabilistic seismic hazard of the ensemble in the range of 0.10 g -2.32 g for 475 years of return period using a systematic 1D/2D/3D site response analysis. Liquefaction potential and landslide susceptibility index adds secondary hazard to both geohazard and seismic hazard regime for a comprehensive seismic hazard microzonation of the important cities and urban centers in the tectonic ensemble. The damage states modelled using capacity spectrum method on prevailing building types for the surface-consistent Probabilistic Peak Ground Acceleration (PGA) by Seismic Loss Estimation using a Logic Tree Approach (SELENA) are found to be aligned with the reported damage scenarios of most prevalent reinforced concrete buildings triggered by large historical earthquakes in each of the tectonic provinces of the Ensemble.