Seismic Microzonation of Densely Populated Area of Kathmandu Valley of Nepal using Microtremor Observations

Seismic microzonation of the Kathmandu Valley reveals that areas with thick lake sediments, particularly near the valley's center, experience dominant amplification periods approaching 2 seconds. This finding indicates a heightened risk for long-period shaking during future earthquakes in densely populated urban zones, where tall structures and bridges with similar natural periods are prevalent. The study employed horizontal-to-vertical spectral ratio analysis of ambient noise recordings to map seismic site response variability, providing critical insights for earthquake hazard assessment in this historically vulnerable region.

Paudyal, Y. R., Bhandary, N. P., & Yatabe, R. (2012). Seismic Microzonation of Densely Populated Area of Kathmandu Valley of Nepal using Microtremor Observations. Journal of Earthquake Engineering, 16(8), 1208–1229. https://doi.org/10.1080/13632469.2012.693242