In order to increase the exploration depth of Rayleigh wave, new idea that dif-ferent from the former principles in data acquisition was applied. Suitable data acquisition parameter was given out on the basis of large...In order to increase the exploration depth of Rayleigh wave, new idea that dif-ferent from the former principles in data acquisition was applied. Suitable data acquisition parameter was given out on the basis of large amount of experiments. By reducing the group interval, the low frequency signal are enhanced instead of been attenuated. Fur-thermore, to solve the problem that the precision of Rayleigh wave exploration method count much to the signal-to-noise ratio, some preprocessing methods were put forward. By using zero shift rectifying, digital F-K filtering and cutting, noises can be effectively eliminated.展开更多
In this work, we present the results of processing and interpretation of part of crustal seismic profile MS-24, acquired about 30 years ago. This line is oriented NW-SE and crosses the external front of the Calabrian ...In this work, we present the results of processing and interpretation of part of crustal seismic profile MS-24, acquired about 30 years ago. This line is oriented NW-SE and crosses the external front of the Calabrian Arc. In order to better image the complex features that characterize this margin, we applied an advanced seismic processing aiming at defining an accurate velocity field by using iteratively the pre-stack depth migration and theoretical considerations. The reprocessed data give more information about a high amplitude reflector associated to velocity inversion. New re-processed seismic data highlighted the presence of morphological features possibly related to fluid migration, which could explain the relationship between velocity inversion and free gas presence,展开更多
The partial derivative equations of Zoeppritz equations are established and the derivatives of each matrix entry with respect to wave vectors are derived in this paper.By solving the partial derivative equations we ob...The partial derivative equations of Zoeppritz equations are established and the derivatives of each matrix entry with respect to wave vectors are derived in this paper.By solving the partial derivative equations we obtained the partial derivatives of seismic wave reflection coefficients with respect to wave vectors,and computed the Goos-Hnchen shift for reflected P-and VS-waves.By plotting the curves of Goos-Hnchen shift,we gained some new insight into the lateral shift of seismic reflection wave.The lateral shifts are very large for glancing wave or the wave of the incidence angle near the critical angle,meaning that the seismic wave propagates a long distance along the reflection interface before returning to the first medium.For the reflection waves of incidence angles away from the critical angle,the lateral shift is in the same order of magnitude as the wavelength.The lateral shift varies significantly with different reflection interfaces.For example,the reflected P-wave has a negative shift at the reflection interface between mudstone and sandstone.The reflected VS-wave has a large lateral shift at or near the critical angle.The lateral shift of the reflected VS-wave tends to be zero when the incidence angle approaches 90°.These observations suggest that Goos-Hnchen effect has a great influence on the reflection wave of wide-angles.The correction for the error caused by Goos-Hnchen effect,therefore,should be made before seismic data processing,such as the depth migration and the normal-moveout correction.With the theoretical foundation established in this paper,we can further study the correction of Goos-Hnchen effect for the reflection wave of large incidence angle.展开更多
文摘In order to increase the exploration depth of Rayleigh wave, new idea that dif-ferent from the former principles in data acquisition was applied. Suitable data acquisition parameter was given out on the basis of large amount of experiments. By reducing the group interval, the low frequency signal are enhanced instead of been attenuated. Fur-thermore, to solve the problem that the precision of Rayleigh wave exploration method count much to the signal-to-noise ratio, some preprocessing methods were put forward. By using zero shift rectifying, digital F-K filtering and cutting, noises can be effectively eliminated.
文摘In this work, we present the results of processing and interpretation of part of crustal seismic profile MS-24, acquired about 30 years ago. This line is oriented NW-SE and crosses the external front of the Calabrian Arc. In order to better image the complex features that characterize this margin, we applied an advanced seismic processing aiming at defining an accurate velocity field by using iteratively the pre-stack depth migration and theoretical considerations. The reprocessed data give more information about a high amplitude reflector associated to velocity inversion. New re-processed seismic data highlighted the presence of morphological features possibly related to fluid migration, which could explain the relationship between velocity inversion and free gas presence,
基金supported by Funding Project for Academic Human Resources Development in Institutions of Higher Learning (Grant No. PHR201107145)
文摘The partial derivative equations of Zoeppritz equations are established and the derivatives of each matrix entry with respect to wave vectors are derived in this paper.By solving the partial derivative equations we obtained the partial derivatives of seismic wave reflection coefficients with respect to wave vectors,and computed the Goos-Hnchen shift for reflected P-and VS-waves.By plotting the curves of Goos-Hnchen shift,we gained some new insight into the lateral shift of seismic reflection wave.The lateral shifts are very large for glancing wave or the wave of the incidence angle near the critical angle,meaning that the seismic wave propagates a long distance along the reflection interface before returning to the first medium.For the reflection waves of incidence angles away from the critical angle,the lateral shift is in the same order of magnitude as the wavelength.The lateral shift varies significantly with different reflection interfaces.For example,the reflected P-wave has a negative shift at the reflection interface between mudstone and sandstone.The reflected VS-wave has a large lateral shift at or near the critical angle.The lateral shift of the reflected VS-wave tends to be zero when the incidence angle approaches 90°.These observations suggest that Goos-Hnchen effect has a great influence on the reflection wave of wide-angles.The correction for the error caused by Goos-Hnchen effect,therefore,should be made before seismic data processing,such as the depth migration and the normal-moveout correction.With the theoretical foundation established in this paper,we can further study the correction of Goos-Hnchen effect for the reflection wave of large incidence angle.
