Fluid sensitivity study of elastic parameters in lowmedium porosity and permeability reservoir rocks

中低孔渗储层岩石弹性参数的流体敏感性研究(英文)

In this article,based on the acoustic measurements of core samples obtained from the low to medium porosity and permeability reservoirs in the WXS Depression,the densities and P and S wave velocities of these core samples were obtained.Then based on these data,a series of elastic parameters were computed.From the basic theory and previous pore fluid research results,we derived a new fluid identification factor（F）.Using the relative variations,Ag/w and Ao/w,of the elastic parameters between gas and water saturated samples and between oil and water saturated samples,λρ,σHSFIF,Kρ,λρ-2μρ,and F as quantitative indicators,we evaluate the sensitivity of the different fluid identification factors to identify reservoir fluids and validate the effects by crossplots.These confirm that the new fluid identification factor（F） is more sensitive for distinguishing oil and water than the traditional method and is more favorable for fliud identification in low to medium porosity and permeability reservoirs.

本文从WXS凹陷中低孔渗储层岩石声波实验出发,以岩样的纵横波速度和密度为基础数据,求取出一系列的弹性参数,包括纵横波波速比、纵波波阻抗、横波波阻抗、泊松比、拉梅常数、剪切模量、体积模量、杨氏模量,等等。在前人的孔隙流体识别究基础上,综合相关理论和实验分析,构建了一个新的流体识别因子F。以饱和流体岩石弹性参数及其组合参数的相对变化量Ag/w和Ao/w为定量指标,评价各流体识别因子的流体识别效果,并采用交会图技术进行了验证。新流体敏感因子在传统较难分辨的孔隙流体"水"和"油"的区别上具有良好效果,有利于提高中低孔渗储层流体识别的成功率。