Abstract:Waveform distortion of supercritical reflection wavelet is a phase shifting phenomenon, it depends on reflector form, physical properties of the both sides of reflecting surface, and the incident angle of seismic wave. On some special assumptions, the relation between seismic velocity and the phase shift of supercritical reflection wavelet can be derived from kinematic and dynamic characteristics of seismic waves. The velocity can be obtained by comparing curve with theoretical curve plotted according to this relation. The velocity determination takes the following steps: (1) some lateral velocity variation models are assumed to calculate theoretical curve templates; <2) standard phase shift curves of a wavelet are determined, then compared with real seismic wavelet 50 as to pick the delay time t, phase shift r and circular frequency ω; <3) actual phase shift and amplitude ratia versus phase shift are derived from parameters such as circular frequency ω, offest χ, etc; <4) actual curves are compared with theoretical curves to calculate the velacity at corresponding offset χ. All wavelets of all seismic traces are treated according to the above mentioned steps to get their velocities, lateral velaeity variations then being knawn.
收稿日期: 1985-08-31
引用本文:
徐盛岩, 张中杰, 何樵登. 用超临界反射子波波形畸变测定速度的横向变化[J]. 石油地球物理勘探, 1986, 21(5): 512-522.
Xu Shengyan. The determination of lateral velocity variations by the waveform distortion of supercritical reflection wavelet. OGP, 1986, 21(5): 512-522.