频率域2.5-D井间波形层析成像及其实际应用

从频率域3-D声波波动方程出发，结合井间观测方式的特点，基于Tarantola广义反演理论，提出了一种频率域2.5-D井间波形层析成像方法.数值模型试验结果表明：该方法对薄层厚度的分辨能力能达到约主频波长的1/4，且分辨率显著高于走时层析成像，尤其垂直分辨率有实质改善.模拟资料的抗噪试验表明：在信噪比为0.8的情况下，随机噪声对波形层析成像的影响较小；而相干噪声对全波形层析成像的影响显著，特别是初至波附近的强振幅干扰影响更为严重.井间实际资料的试处理结果表明：波形层析成像能很好地刻画井间介质的分布情况与储层连通性，对于油藏开发阶段的方案实施具有指导意义.

The 2.5-D cross-well waveform tomography in the frequent domain and its practical application

Based on the 3-D acoustic equation and Tarantola's generalized inversion theorem,taking into consideration the character of cross-well survey,a 2.5-D cross-well waveform tomography method in the frequency domain is presented here.The experimental results of the numeric models show that this method can achieve a resolution for the thin horizontal layers up to 1/4 of the dominant frequency wave length,and its resolution is obviously higher than the travel-time tomography,especially the vertical resolution is substantially improved.The anti-noise tests with synthetic data show that the random noise affects slightly the quality of the waveform tomography in the case of N/S=0.8,but the coherent noise affects greatly,especially the strong amplitude disturbance near the first-arrival has a serious effect.The waveform inversion result of practical data shows that the waveform tomography can depict the distribution of the cross-well medium's property and the reservoir connectivity,and is of importance for oil development.