Land Use Exposure to Deterministic Seismic Hazard in Delhi National Capital Territory

Indian cities are growing at a faster rate due to urban sprawl and urban dynamics. Delhi is one of the seismic hazard-prone cities in the world located next to the Himalayan range, home of nearly eighteen million. Construction of high rise buildings even in the hazard-prone areas has become common due to high population intensity in major Indian cities. Damages to the livelihood and lives happen only when earthquakes interact with infrastructures and population. This study presents the details of the deterministic seismic hazard analysis (DSHA) of Delhi considering latest available information of seismic events and sources, within a distance of 500 km radius from the outermost boundaries of the city. Earthquake data catalog for the study region was developed by collecting seismic data from various agencies. Seismic event magnitudes were converted into a homogenized unified moment magnitude scale. A seismotectonic map for the study region was developed by superimposing the declustered earthquake event on the seismic source map of the region. The study area was divided into grids of size 0.02 degrees x0.02 degrees and DSHA was performed using attenuation relationship available for the active tectonic region. Peak ground acceleration (PGA) values were evaluated for 84th percentile values at the center of each of the grid points. Land use (LU) map for the study region was also generated using Landsat8 data. Hazard contour map, ward-wise administrative map, and LU map for the year 2016 are presented in this paper to revisit the seismic risk prevailing in the region.