砂泥岩干岩石模量估计  

Estimation of the dry rock modulus for shaly sandsone

作　　者：魏冰涛 杨国权[1] 李振春[1] 

机构地区：[1]中国石油大学(华东)地球科学与技术学院,青岛266580

出　　处：《地球物理学进展》2016年第3期1202-1206,共5页Progress in Geophysics

基　　金：国家重点基础研究发展计划(973)课题(2014CB239006;2011CB202402);国家自然科学基金(41104069;41274124)联合资助

摘　　要：流体替换是了解和预测地震波速度和波阻抗如何依赖孔隙流体变化的有效工具,参数多、不确定性大是流体替代的特点,其中,干岩石模量是链接流体和饱和岩石的关键,也是Gassmann方程的基础,因此干岩石模量值的确定是流体替代的难点.前人对干岩石模量也进行了大量的研究,提出了许多经典模型:疏松砂岩模型、Kuster-Toksoz模型、自相容模型(selfconsistent模型)、微分有效介质模型(DEM模型)等,但这些模型都具有一定的局限性,本文通过对Gassmann方程图形分析方法(Mavko and Mukerji,1995)的研究,提出了一种计算干岩石模量的新方法.通过实际的岩样数据分析这几种算法的应用效果,研究结果认为求取干岩石模量时,本文提出的新方法具有很好的应用效果.Fluid substitution is a effective physical tool with which we can understand and predict the variation of seismic wave velocity and its impedance due to the change of pore-fluid. There are two main problems in fluid substitution,such as too many parameters and a great deal of uncertainties. For example,the modulus of dry rocks is the key parameter for the relation of saturated rock and fluid, therefore it is the foundation of Gassmann equation.However,it is pretty difficult to calculate dry rock modulus. Many researchers have made many efforts to estimate dry rock modulus.As a result,many of the classic models have been put forward,such as unconsolidated sandstone model,Kuster and Toksoz model,selfconsistent model（ SCA）, differential effective medium model（ DEM）,etc. But all these methods due to the limitations of their own assumptions,so they can not obtain satisfactory results when applied to different actual data. In this paper,we propose a new method in order to have a good grasp of the dry rock modulus. This method is inspired by the graphical interpretation of Gassmann equation（ Mavko and Mukerji,1995）. With the help of the actual sample data,we test these methods and analyze the effect of these algorithms. As we have expected,the new method has a better effect and more attention should be paid to it.

关 键 词：疏松砂岩模型 K-T模型 自相容模型 DEM模型 GASSMANN方程 干岩石模量 岩石物理 Reuss 

分 类 号：P313[天文地球—固体地球物理学]