• Title/Summary/Keyword: Ultrasonic ranging

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Surface Wave Method: Focused on Active Method (표면파 탐사: 능동 탐사법을 중심으로)

  • Kim, Bitnarae;Cho, Ahyun;Cho, Sung Oh;Nam, Myung Jin;Pyun, Sukjoon;Hayashi, Koich
    • Geophysics and Geophysical Exploration
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    • v.22 no.4
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    • pp.210-224
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    • 2019
  • Surface wave (SW) surveys, which have been applied to numerous application fields ranging from micro-scale ultrasonic analysis to geological scale analysis, are widely used to monitor near-surface stability. The survey method is basically made through analysis on dispersion of SW propagating along the earth surface, in order to delineate shear velocity structure of subsurface. SW survey data are inverted with assuming one-dimensional (1D) layered-earth in order to recover shear wave velocities of each layer, after being analyzed to make the dispersion curve that shows phase velocity of SW with respect to frequency. This study reviews surface wave surveys with explaining the basic theory including the characteristics of dispersion and the procedure of general data processing. Even though surface wave surveys can be categorized into active and passive methods, this paper focuses only on active surface wave methods which includes continuous SW (CSW), spectral analysis of SW (SASW) and multichannel analysis of SW (MASW). Passive method will be reviewed in the subsequent paper.