Abstract: The seismic impedance inversion is bandlimited. Because the breadth of frequency band of the seismic inversion constrained by well log is limited. The research in this paper is focused on how to expand the breadth of frequency band in seismic impedance inversion and to improve the resolution of seismic data. By using the logging constrained seismic impedance inversion data, the seismic data and the log data, we studied the relative stability of reservoir space and estimated and inversed the seismic impedance data with higher resolutions based on correlation function analysis and geological modeling technique used for reference. Considering the spatial correlation and distinguishability of the geologic body, we select the correlation radius in the range from the maximum point of fitted correlation function to the end of smoother section behind the point of inflexion. When calculating the objective function, we consider both the current weight coefficient and the one of extrapolating point to obtain more stable and reliable results. By synthesis simulation, we can distinguish the smaller sand body.

Key words: relative stability of reservoir space, correlation function, synthesis simulation, numerical computation

摘要： 由于地震资料是带限的,而井资料约束反演过程中的地震反演频带的展宽也是有一定限度的,使得反演地震波阻抗也是带限的。如何进一步拓宽反演地震波阻抗的频带宽度,提高地震资料的分辨率是文中研究的内容。利用井约束下的地震反演波阻抗资料、地震资料及井资料,借鉴地质模拟技术,研究如何利用地层的空间相对稳定性特征,通过相关函数的分析,估计反演更高分辨率的地震波阻抗资料。考虑到地质体空间的相关性及分辨率,相关半径取相关函数从最大点到第1个极值点的范围。在目标函数的计算过程中,既考虑当前计算点的权系数信息,又考虑井外推时的权系数信息,这样使计算结果更加稳定可靠。通过综合模拟计算,能够识别较小砂体。

关键词: 储层的空间相对稳定性, 相关函数, 综合模拟, 数值计算