Seismic Multi-wave Q Compensation Based On Prc-stack Data Analysis

With the development of seismic exploration, the accuracy for the exploration isbecoming more important. However, the subsurface medium is imperfectly elasticthat the energy of seismic waves will be absorbed when travelling through suchmedium, making the main frequency and signal to noise ratio of the deep reflectionbecome lower and the spectrum band becomes narrower, resulting in deterioration ofthe quality of deep seismic data. Therefore, researches on the quality factor Q, whichdescribes the viscous elasticity of the subsurface medium, are needed to improve thequality of seismic data. Multi-wave multi-component seismic data include moreinformation of subsurface, but unlike P-wave, the main frequency decrease ofconverted S-wave will impact the comparison and integrated applications ofmulti-wave, so researches on multi-wave Q estimation and Q compensation havebeen done in order to achieve the purpose of improving the quality of seismic data.Lots of work has been done in this area. There are many mature methods on theestimation of P-wave quality factor, but the quality factor estimation ofconverted-wave in multi-wave seismic exploration is much less. On the basis ofprevious research, studies on the methods of multi-wave quality factor estimationand compensation have been done in this paper. The specific content can besummarized as follows.First of all, the theoretical study on model data was started. Through theforward modeling of one single layer and multiple layers, the phenomenon ofseismic wave attenuation can be seen. Then we used the inverse-Q filter factor inFutterman model to compensate the attenuation and calculated Q values using themethod of Q scanning. Both layered Q and effective Q have been applied andturned out to be proper throughout this process.Then the attenuation processing of practical multi-wave pre-stack seismic datawas developed, in which the effective Q was used. Reasonable Q compensation andestimation methods were obtained after several experiments. All these processeseventually reached the purpose of improving the main frequency and broadeningthe spectrum band of practical seismic data.