This paper studies, under a small disturbance, the responses of seismic transient wave in the visco-elastic media and the analytic solution of the corresponding third-order partial differential equation. A plane wave ...This paper studies, under a small disturbance, the responses of seismic transient wave in the visco-elastic media and the analytic solution of the corresponding third-order partial differential equation. A plane wave solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differ-ential equation with a pulse source is obtained. By the principle of pulse stacking of particle vibration, the result is extended to the solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differential equation with any source. The velocities of seismic wave propagating and the attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are discussed. The velocities of seismic wave propagating and the coefficient of attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are derived, expressed as functions of density of the media, elastic modulus and visco-elastic coefficient. These results can be applied in inversing lithology parameters in geophysical prospecting.展开更多
The seismic records of borehole-to-borehole me- asurements on frequency of 200 Hz in the mi-crostrain range have been analysed. Microplas-ticity manifestations caused by seismic wave are detected on seismic records. I...The seismic records of borehole-to-borehole me- asurements on frequency of 200 Hz in the mi-crostrain range have been analysed. Microplas-ticity manifestations caused by seismic wave are detected on seismic records. It is the lad-der-like stepwise change in amplitude course in some parts of the seismic trace. The step dura-tion (time plateau) presents the amplitude- dependent time delay that shifts the arrival time and protracts pulse front. The microplastic process occurs owing to the anomalous re-alignment of the internal stresses on the micro-structural defects in “elastic” domain. Result is the useful contribution for improvement of the theory of wave attenuation in the rocks. It can also be used in solving the applied problems in material science, seismic prospecting, diagnos-tics etc.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.50490270)the National Basic Research Program of China(Grant Nos.2005CB221501 and 2002CB211707).
文摘This paper studies, under a small disturbance, the responses of seismic transient wave in the visco-elastic media and the analytic solution of the corresponding third-order partial differential equation. A plane wave solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differ-ential equation with a pulse source is obtained. By the principle of pulse stacking of particle vibration, the result is extended to the solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differential equation with any source. The velocities of seismic wave propagating and the attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are discussed. The velocities of seismic wave propagating and the coefficient of attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are derived, expressed as functions of density of the media, elastic modulus and visco-elastic coefficient. These results can be applied in inversing lithology parameters in geophysical prospecting.
文摘The seismic records of borehole-to-borehole me- asurements on frequency of 200 Hz in the mi-crostrain range have been analysed. Microplas-ticity manifestations caused by seismic wave are detected on seismic records. It is the lad-der-like stepwise change in amplitude course in some parts of the seismic trace. The step dura-tion (time plateau) presents the amplitude- dependent time delay that shifts the arrival time and protracts pulse front. The microplastic process occurs owing to the anomalous re-alignment of the internal stresses on the micro-structural defects in “elastic” domain. Result is the useful contribution for improvement of the theory of wave attenuation in the rocks. It can also be used in solving the applied problems in material science, seismic prospecting, diagnos-tics etc.
