用声波测井方法识别剩余油需要解决的两个关键问题  

Two Main Problems in Evaluating Oil and Water in Sandstone by Sonic Waveforms

作　　者：沈建国[1] 陈宇[1] 

机构地区：[1]清华大学物理系

出　　处：《测井技术》2003年第1期30-34,共5页Well Logging Technology

基　　金：中国博士后基金;中博金 (2 0 0 1 ) 5号;辽河油田测井公司联合资助

摘　　要：在频率为 5 0 0～ 14 0 0 0Hz范围内 ,砂岩的声波速度或物理衰减系数随频率的变化而变化 (简称频散 ) ,其变化关系与流体有关 ,这是用声波测井方法解决剩余油问题的物理基础。在实验室内测量上述频率范围内声速的频散随孔隙流体特征不同的变化需要一些特殊的测量方法和装置。给出了用平板砂岩样品测量的波形和处理结果 ;用数值计算的方法讨论了地层的声速随不同的频率变化时声波测井波形的二维谱、模式波的变化 ,肯定了用声波全波波形识别剩余油的可行性和需要解决的技术问题。与以往不同 ,这里利用的是地层声速随不同频率的变化关系 ,所以 ,声波测井波形的处理结果不再是地层的纵、横波速度值 ,而是纵、横波速度随不同频率而变化的函数。The sonic velocities and attenuation of sandstone vary with the frequency in the range 500- 14 000 Hz. It is called dispersion. As the pore fluid characters effect the dispersion, it is possible to use sonic waveforms to evaluate oil and water in sandstone. In order to use this character efficiently, one must measure the frequency dispersion of sandstone in laboratory. Some waveforms measured on the surface of a plate core sample of sandstone and processing result are given. Using real axis integral method, the 2D spectrum, mode waves and synthetic full-waveforms of sonic logs are calculated numerically. Comparing with the normal solid (no dispersion), difference of waveforms is in evidence. Different from the normal uses of sonic logs, the dispersion of the velocities of P wave or S wave is a function of frequency, not a value.

关 键 词：声波测井方法 识别 剩余油 声速 频散 岩心 

分 类 号：TE327[石油与天然气工程—油气田开发工程] P631.814[天文地球—地质矿产勘探]