Multi-Frequency Crosswell Seismic Experiment

다중 주파수 송신원에 의한 공대공 탄성파 실험

  • Lee, Doo-Sung (Information System Engineering, Hansung University)
  • 이두성 (한성대학교 정보시스템공학과)
  • Published : 2007.11.30

Abstract

First arrival signals of multi-frequency crosswell seismic data, acquired in wells drilled in granitic rock, were analyzed to investigate the characteristic behavior of the signals at the shear zones. Dominant frequencies of the sources were; 10-, 20-, 40-, 56-, and 80 kHz. No obvious changes in the waveform at the shear zones were found; however, at the shear zones, some degree of velocity reductions were observed in the signals of all frequency sources. The 80 kHz signal is slightly faster than 10 kHz signal in the survey region, and the velocity difference between the two signals were found largest at the shear zone where the permeability measured greatest in the survey interval.

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