岩石物理建模在东胜气田横波速度预测中的应用

Application of rock physics modeling in shear wave velocity prediction of Dongsheng gasfield

岩石物理建模是地震岩石物理研究的重要内容之一,是建立岩石弹性属性与岩性、物性、含油气性之间的物理联系,其中横波速度是地震储层预测中的重要参数。东胜气田位于鄂尔多斯盆地杭锦旗地区,目的层二叠系下石盒子组气藏为典型的低孔、超低渗致密砂岩气藏,储层非均质性强,常规的纵波阻抗叠置,基于叠后波阻抗反演不能有效的区分储层。针对生产中缺乏横波速度资料的情况,本文采用岩石物理建模的方法预测横波,通过对结果分析认为在东胜气田致密砂岩储层中采用Xu-White模型进行岩石物理建模进行横波预测,结果与实测曲线吻合度高。

Rock physics model ing is one of the important contents of seismic petrophysical research. It is the physical connection between rock elastic properties and lithology, physical properties and hydrocarbon-bearing properties. The shear wave velocity is an important parameter in seismic reservoir prediction. The Dongsheng gasfield is located in the Hangjinqi area of the Ordos basin.Target layer in lower Shihezi formation of Permian is a typical lowporosity and ultra-low-permeability tight sandstone gas reservoir. The reservoir heterogeneity is strong and the conventional longitudinal wave impedance is superimposed. Based on poststack wave impedance inversion, the reservoir cannot be effectively distinguished. In view of the lack of shear wave velocity data in production, this paper uses petrophysical modeling to predict the transverse wave. Through the analysis of the results, it is considered that the XuWhite model is used in the tight sandstone reservoir of Dongsheng gasfield for rock physics modeling for shear wave prediction. It has a good agreement with the measured curve.