基于黏滞—弥散理论的含气砂岩数值模拟与分析

发布时间：2018-05-27 22:38

本文选题：黏滞—弥散 + 斑块饱和模型　；参考：《石油地球物理勘探》2017年04期

【摘要】：黏滞—弥散波动方程理论能够将含油气储层的地震响应特征与频率紧密联系起来,而斑块饱和模型则常用来描述经典含气砂岩的岩石物理特征。根据Johnson理论,通过计算岩石动态体积模量可以得到等效纵波相速度和品质因子的频散关系,改变含气饱和度能够对砂岩中地震波速度的衰减产生十分显著的影响,在地震频段可高达数百米每秒。当地震频率较高时,含气饱和度越高地震波衰减越强;地震频率足够低时,含气饱和度越高地震波衰减越弱。根据Carcione衰减机制,结合叠前相移加插值黏滞—弥散波动方程正演,对三类经典含气砂岩的地震响应特征进行数值模拟,发现增大含气饱和度可使储层下界面反射产生明显"时间延迟",且地震波在欠压实和中等压实的砂岩储层中表现出一定的主频降低现象;渗透率的增大能够改变介质中流体的流动性,但对含气储层的地震响应影响相对较小。
[Abstract]:The viscosis-dispersion wave equation theory can closely relate the seismic response characteristics to the frequency of the oil-bearing reservoir, while the patch saturation model is often used to describe the petrophysical characteristics of the classical gas-bearing sandstone. According to the Johnson theory, the dispersion relationship between the velocity of the equivalent longitudinal wave phase and the quality factor can be obtained by calculating the dynamic bulk modulus of the rock, and the attenuation of seismic wave velocity in sandstone can be greatly affected by changing the gas saturation. Earthquakes can be as high as hundreds of meters per second. The higher the seismic frequency is, the stronger the attenuation of seismic wave is, and the higher the gas saturation is, the weaker the attenuation of seismic wave is. Based on the Carcione attenuation mechanism and the forward modeling of the prestack phase shift and interpolated viscous dispersion wave equation, the seismic response characteristics of three classical gas-bearing sandstone are numerically simulated. It is found that increasing gas saturation can cause obvious "time delay" in the reflection of the lower interface of the reservoir, and the seismic wave in the undercompacted and medium compacted sandstone reservoir shows a certain phenomenon of main frequency reduction. The increase of permeability can change the fluidity of fluid in medium, but it has little effect on seismic response of gas-bearing reservoir.
【作者单位】：油气藏地质及开发工程国家重点实验室(成都理工大学);中国石油化工股份有限公司勘探分公司;中国石油化工股份有限公司西南油气田分公司;
【基金】：国家自然科学基金石油化工联合基金(U1562111) 国家科技重大专项(2016ZX05002-004-010)联合资助
【分类号】：P631.4

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