含水泥质砂岩导电特性的机理研究

Study of the Mechanism of Electric Conductivity in Water-bearing Shaly Sands

为研究含水泥质砂岩导电特性的机理,由单毛管双电层电位理论和阳离子交换量与Zeta电位的关系,得到了毛管径向电位分布和离子浓度分布。根据离子浓度分布与液体导电理论,结合串联毛管束模型,推导了含水泥质砂岩电导率的计算公式。利用此公式进行了理论计算,计算结果表明该理论与W-S模型有较好的一致性。并用该理论讨论了W-S模型的适用范围及阳离子交换量与渗透率对模型中B系数的影响。

According to the theory of electrical double layer potential in a capillary and the relation between Zeta potential and cation exchange capacity, the radial distributions of potential and ions concentration are assured. According to the distribution of ions concentration, the theory electric conductivity of liquid and in series capillaries model, the conductivity expression of waterbearing shaly sands is deduced. The computing results obtained by the expression show the theory accords with W-S model. In adition, the applied range of W-S model and the influnces of cation exchange capacity and permeability on B coefficient of W-S model are disscussed.