摘要
以苏里格气田为例,详细讨论了弹性参数与含气性的关系:①拉梅常数(λ)、剪切模量(μ)和体积密度(ρ)与岩性和孔隙度有关,在岩性不变情况下,孔隙度增大,λ、μ和ρ都要减小,λ减小的幅度最大,ρ次之,μ几乎不受孔隙流体的影响;②孔隙含油或含气,λ/μ和纵、横波速度比(vp/vs)比值都下降,且λ/μ下降速度比vp/vs的快,含水时这两项比值均随孔隙度增加而增大;③λ/μ比值与含气饱和度呈非线性关系,且这种关系受孔隙度的影响;但ρ/μ比值只与孔隙度有关。因此,可以由ρ/μ预测孔隙度值,再根据λ/μ估计含气饱和度。依据流体饱和多孔介质岩石物理理论,建立了该区拉梅常数、剪切模量和体积密度与孔隙度、饱和度的关系式,结合叠前反演和从反演的弹性参数获得的泊松比,预测岩性和气藏分布、估计储层孔隙度和含气饱和度。钻井结果验证了预测结果的可靠性。
Taking Sulige gasfield as instance, the relation between elastic parameters and gas reservoir has been discussed in detail in this paper. The research results include: Lam constant ( λ), shear modulus (μ ) and mass density ( ρ) all bear relation to lithology and porosity , and decrease with porosity increasing when lithology doesn't vary. The decreasing grade of is largest, next is , and is hardly affected when pore was filled with fluid. the ratios of / and vp/vs decrease when pore was filled with gas or oil, and / decrease more rapidly than vp/vs . But the ratios increase when pore was filled with water. / gas saturation relation is nonlinear and relate to porosity. But / porosity relation is hardly affected by saturation. So we can estimate porosity by using / then saturation by using / Based on the rock physical theory of fluid saturated porous media, the elastic parameter-porosity relation and elastic parameter-saturation relation have been build in the study area. Combining with prestack inversion and Paisson's ratio from the inverse elastic parameters, it can be used to predict the distributions of lithology and gas and estimate the porosity and saturation. The later drilling testified the reliability of the estimated results.
出处
《中国石油勘探》
CAS
2006年第4期80-84,共5页
China Petroleum Exploration
基金
国家重点基础研究专项"高效天然气藏形成分布与凝析低效气藏经济开发基础研究"(2001CB20915)
中国石油勘探开发研究院创新基金"高精度波场延拓法叠前广义弹性参数反演"(2005-1-A)。
关键词
弹性参数
岩性油气藏
叠前反演
孑L隙度
饱和度
elastic parameter
lithologic oil-gas reservoir
prestack inversion
porosity
saturation
