【摘要】 品质因子Q本身反映了地表层的岩石物理特性,但表层Q值的求取一直是研究难点。利用表层模型反演及面波衰减的Q模型可反演出近地表Q值,但求取的表层Q值精度不够,不能满足高精度地震勘探的需要。本文提出了一种利用双井微测井资料估算近地表Q值的方法,通过建立求解地面和井下检波器的峰值频率变化方程组,获得了近地表Q值的解析解。利用大庆油田实际资料对文中方法进行验算的结果表明,算法稳定,计算的表层Q值合理,用反Q滤波可以在时间、频率和空间三个域内有效地消除近地表影响,尤其是对地震信号相位的影响,提高了地震资料的分辨率。更多还原

【Abstract】 Quality factor Q itself reflects the rock physical properties of near surface layer,however the estimation of Q value for the near surface layer has been always a difficult point in the research.The near surface Q value can be inverted either by near surface model inversion or by ground wave attenuation Q model,but its accuracy is not enough and can not meet the need of high accuracy seismic exploration.A near surface Q value method based on the datasets of the uphole survey in double hole was proposed in this paper,by building and solving the equation group which describes the peak value changing for the surface geophones and downhole geophones,the analytic solution for the near surface Q value was acquired.The testing results for the method based on field datasets from Daqing Oilfield show that the algorithm is stable,acuired Q value is reasonable,the reverse Q filtering using the acquired Q value could effectively eliminate near surface affects in time,frequency and space domain,especially the affect from the seismic signal phase,so the seismic resolution was raised.更多还原