论文部分内容阅读
物理模型实验揭示：流体饱和度、孔隙流体的特性，地震波的频率和岩石孔隙的纵横向尺寸比对地震波的衰减都有很大的影响。本文借鉴滞弹性弛豫热激活过程的研究来描述地震波在饱和砂岩中的衰减机理。首先研究成分单一的长石砂岩在水、原油、油水混合液饱和条件下的弛豫特性，发现产生弛豫峰的王要原因是孔隙液体与长石砂岩孔隙界面上的相界弛豫。对于由初隙液体饱和的多孔岩石可以用普遍化的Voigt三参数模型和Cole－Cole分布描述。由于孔隙液体饱和的多孔岩石中普遍存在着多重弛豫的叠加，所以造成弛豫峰变宽。实验表明，油水混合液饱和砂岩的弛豫最宽，石油饱和砂岩比泵油饱和砂岩的分布宽度稍大，水饱和砂岩的弛豫峰较窄。
Physical model experiments revealed that the fluid saturation, the characteristics of pore fluid, the frequency of seismic waves and the aspect ratio of rock pores have a great influence on the attenuation of seismic waves. This paper draws lessons from the study of the process of asexual relaxation heat activation to describe the attenuation mechanism of seismic waves in saturated sandstone. Firstly, the relaxation behavior of monolithic feldspar sandstone under the saturated condition of water, crude oil and oil-water mixture was studied. The reason for the relaxation peak was found to be the relaxation of the phase boundary between the pore liquid and the interface of feldspar sandstone. For porous rocks saturated with primary fluid, the generalized Voigt three-parameter model and Cole-Cole distribution can be described. The relaxation peaks are broadened due to the superposition of multiple relaxations in porous rock saturated with porous liquid. Experiments show that the oil-water mixture has the widest relaxation of saturated sandstone, the oil-saturated sandstone is slightly wider than the saturated oil-saturated sandstone, and the relaxation peak of water-saturated sandstone is narrower.