Document Type : Original Research Paper

Authors

1 International Institute of Earthquake Engineering and Seismology, Tehran, Iran

2 Institute of Geophysics, University of Tehran, Tehran, Iran Seismotectonic Department, Geological Survey of Iran, Tehran, Iran

Abstract

The shear wave velocity structure in Bam city is estimated in this paper. A double circle array observation of microtremors was conducted in south-east of Bam. Spatial Auto-correlation Coefficient (SPAC) method was utilized to determine phase velocity dispersion curve of Rayleigh wave in frequency range from 1.6 to 2.3 Hz. An inversion scheme based on Genetic Algorithm was employed to estimate the VS profile up to 400 m at the site under study. The inverted shear wave velocities are compared with the available down-hole data, and are found to be in good agreement. It verified the reliability of the estimated shear wave velocity profile and confirmed the use of SPAC method as a good alternative to the conventional approaches due to relatively low costs, ease of operation and analysis, accuracy, and ability to explore soil profile up to large depth.

Keywords

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