频谱一致性Q因子反演方法

Q-factor inversion based on spectral consistency

1.中国石油大学(北京)油气资源与探测国家重点实验室,北京102249;
2.中国石油新疆油田分公司勘探开发研究院,新疆克拉玛依834000

1. State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China;
2. Petroleum Exploration and Development Institute,PetroChina Xinjiang Oilfield Company,Karamay 834000,China

地层品质因子Q能够定量表征地层吸收对地震信号的衰减效应,对高分辨率地震数据处理和油气检测均具有重要作用。针对现有Q因子估算方法抗噪性弱、稳定性差等问题,提出了一种基于频谱一致性准则的Q因子反演方法。该方法基于粘弹性介质地震波传播理论,将不同时间接收的地震信号反向传播到某一位置,基于反向传播之后频谱特征的一致性对Q因子进行反演。不同于谱比法和质心频移法,该方法不是基于对数谱斜率和质心频移等地震频谱的某个特定属性,而是基于地震频谱在整体特征上的一致性对Q因子进行反演和估算,其反演结果的稳定性和抗噪性更好。理论模型和实际数据的实验结果表明,采用该方法能够得到更加可靠的Q模型,其补偿结果较好地恢复了高分辨率地震数据的反射特征。

The formation quality factor,Q,can quantitatively characterize the attenuation effect of formation absorption on seismic signals and it plays an important role in high-resolution seismic data processing and oil and gas detection.To address the problems of weak anti-noise and poor stability of the existing Q-factor estimation methods,a Q-factor inversion method based on the spectral consistency criterion is proposed.Based on the theory of seismic wave propagation in a viscoelastic medium,the method reversely propagates seismic signals received at different times to a certain position and inverts the Q factor based on the consistency of spectral characteristics after reverse propagation.In contrast to the spectral ratio method and the centroid frequency shift method,this method is not based on a specific property of the seismic spectrum,such as logarithmic spectral slope or centroid frequency shift.However,based on the consistency of the seismic spectrum in the overall characteristics of the inversion of the Q factor and estimation,the inversion results have better stability and noise immunity.The experimental results of the theoretical model and actual data show that this method can obtain a more reliable Q model,and the compensation result can restore the reflection characteristics of high-resolution seismic data.

国家自然科学基金(42074141,41874141)资助。

10.3969/j.issn.1000-1441.2023.01.008