Investigation and application of Q-value in near-surface continuous medium area
In order to improve the resolution of seismic data,absorption compensation must be applied to the original data,and the accuracy of the near-surface Q model must be enhanced.In view of the serious absorption and attenuation of seismic waves near the surface of continuous media with loose structure,fast velocity change and large thickness of the weathered layer,quality factor investigation and near-surface Q modeling were researched.The results showed that:1)The uphole in two holes survey method of excitation in the well while receiving at the surface and bottom of the well can improve the accuracy of quality factor;2)The Q-value in near-surface survey results covering the velocity and thickness of different weathered layers together with sufficient sample data ensure the statistical law of Q-v empirical formula;3)The high-precision near-surface model of uphole survey lays a foundation for the construction of layered near-surface Q model;4)The continuous medium near-surface Q model more truly reflects the distribution law of the actual near-surface Q-value.The above results show that improving resolution has certain guiding significance for seismic exploration and acquisition in desert,loess tableland and other work areas where the near surface is a continuous medium.
near surfacecontinuous mediumQ-value surveyabsorption attenuationabsorption compensationuphole survey in double holenear-surface Q model