摘要
地震波阻抗反演是储层预测的核心环节,而构建精确的地震正演模型则是实现高分辨率波阻抗反演的基础。然而,当地下速度存在剧烈横向变化时,传统的以一维地震子波为基础的褶积正演模型难以实现对深度域成像剖面的准确模拟和表征,严重影响波阻抗反演结果的精度和可靠性。为此,提出了一种基于点扩散函数的非平稳空间深度域褶积正演方法。首先,根据线性Born正演理论推导地震成像剖面与地下反射系数的精确映射关系;然后,在此基础上构建以点扩散函数为多维深度域地震子波的精确褶积正演模型;最后,基于射线理论格林函数的点扩散函数高效算法,可以大幅提高点扩散函数的计算效率。简单水平层状模型和复杂Marmousi模型的深度域褶积正演测试验证了该方法的正确性和有效性。
Seismic wave impedance inversion is the core of reservoir prediction,and the construction of an accu-rate seismic forward model is the basis of realizing high-resolution wave impedance inversion.However,it is difficult for the traditional convolution forward models based on one-dimensional seismic wavelet to accurately simulate and characterize the imaging profile in the depth domain when there is a drastic lateral change in the subsurface velocity,which seriously affects the accuracy and reliability of wave impedance inversion results.For this reason,this paper proposes a forward modeling method of convolution in the depth domain of non-sta-tionary space based on point spread function.Firstly,the accurate mapping relationship between seismic ima-ging profile and underground reflection coefficient is derived according to the linear Born forward modeling theory.Then,an accurate convolution forward model is constructed with the point spread function as the seis-mic wavelet in the multi-dimensional depth domain.Finally,the efficient algorithm of point spread function based on Green’s function of the ray theory can greatly improve the computational efficiency of the point spread function.The correctness and effectiveness of the proposed method are verified by the depth-domain convolu-tion forward modeling tests of the simple horizontal layered model and the complex Marmousi model.
作者
沈蔚
岳玉波
秦宁
SHEN Wei;YUE Yubo;QIN Ning(School of Earth Science and Technology,Southwest Petroleum University,Chengdu,Sichuan 610500,China;Geophysical Research Institute,Shengli Oilfield Company,SINOPEC,Dongying,Shandong 257022,China)
出处
《石油地球物理勘探》
北大核心
2025年第4期951-957,共7页
Oil Geophysical Prospecting
基金
国家自然科学基金项目“快速成像域真振幅最小二乘偏移”(42074173)
“基于射线理论点扩散函数的深度域波阻抗反演”(42374161)
四川省自然科学基金项目“面向角度相关反射系数的高保真地震反演成像方法研究”(2024NSFSC0082)联合资助。
关键词
深度域
波阻抗反演
点扩散函数
褶积模型
depth domain
wave impedance inversion
point spread function
convolutional model
