摘要
储层中裂缝的存在必然引起地震波传播特征的变化，波场特征的变化同储层中裂缝密度和裂缝方位有关，因而这种特征变化可以作为检测裂隙存在的有效手段。本文利用物理模型方法研究了裂缝密度和方位角变化对地震波传播特征的影响。实验发现：裂缝密度较高时，可以观测到明显的横波分裂现象；而裂缝密度较低时，仅能观测到微小的速度异常。同时快横渡与慢横波在振幅和频率特征上也具有明显差异。这些波场特征的分析对于裂缝检测具有重要意义。
Fractures in reservoir must cause the variation of seismic wave characteristic.The variation of wave field characteristic is closely related to the density and azimuths of fractures in reservoir, so that it may be an effective means of ascertaining the fractures. Physical model experiment was done to analyse how variations of fracture density and fracture azimuth influence on seismic wave characteristic.Model experiment says that obvious shear wave splitting may be found when fractures are dense, and that only slight velocity variation may be observed when fractures are less dense. Fast shear wave is obviously different from slow shear wave in amplitude and frequency characteristics. The analysis of wave field characteristics is of great significance to fracture prediction.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
1999年第6期675-681,共7页
Oil Geophysical Prospecting
基金
国家自然科学基金
大庆石油管理局的联合资助
关键词
裂缝模型
波场特征
储集层
油气勘探
超声波勘探
fracture model,fracture density,fracture azimuth,shear wave splitting, wave field characteristic,wave velocity anomaly
