利用泰勒级数展开的振幅谱积分差值的Q值估计方法  

Amplitude spectral integral difference method for Q estimation based on Taylor series expansion

作　　者：张瑾 张国书 王彦国 李红星[1] ZHANG Jin;ZHANG Guoshu;WANG Yanguo;LI Hongxing(School of Geophysics and Measurement-control Technology,East China University of Technology,Nanchang,Jiangxi 330013,China;School of Nuclear Science and Engineering,East China University of Technology,Nanchang,Jiangxi 330013,China;State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang,Jiangxi 330013,China)

机构地区：[1]东华理工大学地球物理与测控技术学院,江西南昌330013 [2]东华理工大学核科学与技术学院,江西南昌330013 [3]东华理工大学核资源与环境国家重点实验室,江西南昌330013

出　　处：《石油地球物理勘探》2022年第2期320-330,I0003,I0004,共13页Oil Geophysical Prospecting

基　　金：国家自然科学基金项目“多相孔隙介质全频段波频散与衰减机制及其应用研究”(41764006);江西省重点研发计划项目“偶极场聚变物理装置设计及技术可行性研究”(20192ACB80006);江西省自然科学基金项目“基于方向tilt梯度张量的三维磁异常解释方法研究”(20212BAB203005)和“基于改进广义S变换的地震波频变Q值提取与反Q滤波方法研究”(2020BABL201027);核资源与环境国家重点实验室开放基金项目“基于重磁一体化反演的江西相山铀矿田三维地质结构特征研究”(2020NRE25)联合资助。

摘　　要：品质因子Q是地震数据处理和解释中的一个重要参数,可用于提高地震记录纵向分辨率和反映储层特性。在常规Q值估计中,时窗与带宽选择是Q值估计的关键,且噪声干扰也会对Q值估计产生影响。为此,文中提出一种基于泰勒级数展开的振幅谱积分差值方法(ASID)。该方法对振幅衰减项进行二阶泰勒级数展开,利用不同时刻地震子波振幅谱差值建立含有Q值的方程,通过求解方程获取Q值。对比试验表明,相对于常用的对数谱比法(LSR)、中心频移法(CFS)和对数谱面积差法(LSAD),文中所提方法具有受频带宽度和时窗宽度影响小,以及抗干扰能力强的优点,且更适用于含薄层地震记录的Q值估计。此外,将ASID法应用于实际海洋资料的CMP道集中,所得Q值估计结果与LSAD法具有良好的一致性。The quality factor Qis a very important parameter for seismic data processing and interpretation,which can be used to improve the vertical resolution of seismic data and reflect reservoir characteristics.The lengths of time window and bandwidth are two key parameters for Q estimation.In addition,Qestimation is easily susceptible to noise interference.To overcome these problems,this paper introduces a new method called the amplitude spectral integral difference(ASID)method based on Taylor series expansion for Qestimation.In this method,the amplitude attenuation term is first subjected to the second-order Taylor series expansion.Then,an equation including Qvalue is established utilizing the difference between amplitude spectra of seismic wavelets at different moments.Finally,the equation is solved to estimate the Qvalue.Model tests indicate that the ASID method is less influenced by noise interference and the lengths of time window and frequency bandwidth and is more suitable for Qestimation of seismic data with thin layers,compared with the logarithmic spectral ratio(LSR)method,the centroid frequency shift(CFS)method and the logarithmic spectral area difference(LSAD)method.The ASID method is also applied to a CMP gather of marine seismic data.The results of Qestimation by the new method are close to those of the LASD method.

关 键 词：Q值估计 泰勒级数展开 振幅谱 薄层 

分 类 号：P631[天文地球—地质矿产勘探]