地震资料信噪比定量计算及比较  

S/N ratio quantitative calculation and comparison of seismic data

作　　者：张军华[1] 周振晓[1] 钟磊[1] 郑旭刚[1] 单联瑜[2] 徐辉[2] 于海铖[2] 

机构地区：[1]中国石油大学(华东)地球资源与信息学院 [2]胜利油田分公司物探研究院

出　　处：《油气地球物理》2008年第4期9-14,共6页Petroleum Geophysics

摘　　要：系统地介绍和讨论了信噪比估算的5种方法,即能量叠加法、频谱估算法、功率谱估算法、相关法和特征值法。利用模型试算对比了噪声、时窗、道数、频带、构造形态对5种方法估算结果的影响。结果表明:对于低品质的资料,谱值法(频谱或功率谱)具有较高的计算精度;时窗大小对信噪比计算影响较小,功率谱法受时窗大小影响最小;信噪比也有横向分辨能力及精度问题,对于倾斜或弯曲地层,能量叠加法和特征值法的计算精度会大大降低;资料的频带并不是影响信噪比计算结果的主要因素;特征值法本质上是水平信号的分解和组合,适宜较平的地层。研究指出,当以信噪比作为储层横向预测属性进行奇异性检测(裂缝、断层、潜山构造等)时,应选用相关法。Five methods for calculation of S/N ratio are studied and discussed systematically. These methods include energy stack, frequency spectrum estimation, power spectrum estimation, correlation and eigenvalue . Comparing the influence on the calculation of S/N of five different methods, it is shown that, for low quality seismic data, the frequency spectrum and power spectrum estimation method have higher calculating accuracy. The length of time window has smaller influence to the calculation of S/N ratio,which has minimum impact on power spectrum method. The S/N ratio also has horizontal resolution and precision, for dipping and bending layers, the calculation accuracy of energy stack and eigenvalue method is low. The frequency band of seismic data is not the main factor for calculating of S/N ratio. The nature of eigenvalue method is the good for horizontal strata withdecomposition of level signal. If the S/N ratio is used for lateral reservoir prediction or singularity detection, correlation method should be used.

关 键 词：地震资料 信噪比估算 频谱 功率谱 相关 特征值 

分 类 号：P631.443[天文地球—地质矿产勘探] TP323[天文地球—地质学]