Ambient noise H/V spectral ratio in site effects estimation in Fateh jang area, Pakistan

Local geology or local site effect is a crucial component while conducting seismic risk assessment studies. Investigations made by utilization of ambient noise are an effective tool for local site estimation. The present study is conducted to perform site response analysis at 13 different sites within urban settlements of Fateh jang area (Pakistan). The aim of this study was achieved by utilizing Nakamura method or H/V spectral ratio method. Some important local site parameters, e.g., the fundamental frequencies <i<f</i<<sub<0</sub< of soft sediments, amplitudes <i<A</i<<sub<0</sub< of corresponding H/V spectral ratios, and alluvium thicknesses over 13 sites within the study area, were measured and analyzed. The results show that the study area reflects low fundamental frequency <i<f</i<<sub<0</sub<. The fundamental frequencies of the sediments are highly variable and lie in a range of 0.6-13.0 Hz. Similarly, amplification factors at these sites are in the range of 2.0-4.0.