近地表地层品质因子的频率依赖性研究  

Analysis on frequency dependence of near-surface quality factors

作　　者：郑浩 ZHENG Hao(Sinopec Geophysical Research Institute,Nanjing 211103,China)

机构地区：[1]中国石油化工股份有限公司石油物探技术研究院,南京211103

出　　处：《地球物理学进展》2023年第1期419-429,共11页Progress in Geophysics

基　　金：国家自然科学基金企业创新发展联合基金(U19B6003)资助。

摘　　要：近地表吸收参数反演是吸收衰减补偿的关键和基础.首先,对比不同微测井观测系统,选取适用于近地表品质因子估算的单井微测井资料用于频率依赖性分析.在此基础上,提出了一种新的近地表Q值反演方法——双参数拟合算法,该方法通过引入岩石物理分析得到的Q值与频率的经验函数,通过最小二乘遗传算法直接拟合Q值,用以验证Q随频率的变化关系.接着,在计算近地表衰减曲线的过程中,利用多道组合的方式计算得到各层的衰减曲线,用于不同地层的Q值反演.实际资料拟合结果表明,近地表品质因子Q具有较为明显的频率依赖性,随着频率的增加,Q值不断减小,这为近地表高精度Q值反演提供了新的思路.The estimation of the quality factor Q plays a fundamental role in near-surface absorption compensation.Several uphole,downhole and crosshole survey geometries are compared and analyzed in detail,and the uphole survey is chosen for near surface absorption parameters inversion.On this basis,a novel non-linear inversion method,called Two-Parameter Regression Method(TPM),has been proposed to estimate frequency-dependent Q.By introducing the prior information,TPM could inverse the frequency-dependent Q directly.To establish accurate near surface Q model,a novel method is proposed to separate general attenuation curve into the one of each layer.From the results,it turns out that Q is not frequency-independent but changes with frequency,which provides reliable evidence for frequency-dependent Q.

关 键 词：近地表 微测井 Q值 双参数拟合 频率依赖 

分 类 号：P631[天文地球—地质矿产勘探]