井约束地震反演中对声波和密度测井的油气信息补偿与消除

Compensation and elimination of hydrocarbon messages from sonic and density log in seismic inversion

在油气勘探和开发中,井约束地震反演常用于预测油、气层的分布范围和含油、气饱和度或储集层的孔隙度、渗透率等地质参数,但是油、气层反映在测井与地震资料上的信息差异,却使得反演结果往往不能令人满意.文中分析了含油、气对地层性质的影响和油、气层在地震和测井资料上产生信息差异的主要原因,提出了在地震有井约束反演前,必须要根据其反演目的决定对测井资料进行油气信息补偿与消除,并从非理想气体定律和Richard公式出发,给出了对密度测井和声波测井的油气信息补偿与消除的方法.应用实例显示了油气信息补偿前、后井约束地震反演的实际效果.

In petroleum exploration and production, seismic inversion bound by well data is often used to predict reservoirs distribution and oil/gas saturation, or some geological parameters such as porosity, permeability, etc. The inversion results, however, are usually not satisfactory because seismic and log data are different in hydrocarbon messages. In this paper, influences of hydrocarbon on reservoir properties and the main causes resulting in message deferences between seismic and log data are analysed, and it is indicated that a hydrocarbon message compensation or elimination on sonic and density log data is necessary before making seismic inversion. Therefore, the method of message compensation and elimination is given from the Non-ideal gas law and Richard equation. Finally, the real results of seismic inversion bound by well data before and after message compensation and elimination are illustrated by a case.