针对复电阻率法应用广泛的Cole-Cole模型存在模型参数多、与物性参数关联弱等缺点，研究含水煤层复电阻导电机理及阻容模型，旨在发展适应于评价煤层含水性与水压致裂效果的复电阻率法理论与技术。依据电介质理论，在外加交变电场下，煤层含水裂隙既具有离子自由移动产生的电阻性，也具有离子界面堆积产生的电容性;基于激发极化和煤双重介质理论，借鉴岩石毛细管模型，将煤层含水孔裂隙等效成正交裂隙，即将含水孔裂隙的电阻性等效为与外加电场方向平行的裂隙，其电阻值为Rw，将含水孔裂隙的电容性等效为与外加电场方向垂直的裂隙，电容值为Cw;煤层本身电阻为Rc，电容为Cc;构建正交裂隙与煤层组成的含水煤层复电阻模型，由等效水平裂隙Rw、煤层Rc、等效垂直裂隙Cw及煤层Cc的一路串联，组成的3路并联等效电路。实验选取肥煤和无烟煤2种变质程度煤样，测量其在不同含水饱和度下的复电阻实部Rs和虚部X，使用模型拟合，获取相关的电阻电容参数，并计算煤样孔隙率。结果表明:阻容模型对不同含水饱和度煤样复电阻参数拟合良好，模型参数电阻R与电容C随含水饱和度的增加而减小，不同含水饱和度虚部X曲线极值向右偏移，与模型物理意义相同;阻容模型参数可计算孔隙率，与密度法、核磁共振法实测孔隙率匹配较好。基于激发极化理论和双重介质理论建立的复电阻正交裂隙阻容模型物理意义明确，数学计算简单，模型参数可预测煤样孔隙率。

In view of the shortcomings of the Cole-Cole model (is widely used in CR),such as too many model param- eters and weak correlation with physical parameters,in order to develop the theory and technology of CR which is suit- able for evaluating the aquifer property and hydraulic fracturing effect of coal seam,the mechanism and resistance-ca- pacitance model are studied in this paper. According to the dielectric theory,the ions in water-bearing fissures will move and accumulate under the applied alternating electric field,and the movement of ions will generate electric re- sistance,the accumulation of ions will produce capacitance. Based on the theory of induced polarization and coal dualporosity medium,and referring to the rock capillary model,the coal seam pores and fissures are equivalent to orthogo- nal fractures. The resistance value of coal seam pores and fissures is the resistance value Rw of horizontal fracture,and the capacitance value is the capacitance value Cw of vertical fracture,the resistance of coal seam itself is Rc and the ca- pacitance is Cc . The model of water-bearing coal seam is composed of orthogonal fracture and coal seam,and a three- way parallel equivalent circuit consists of equivalent horizontal fracture Rw ,coal seam Rc ,equivalent vertical fracture Cw and coal seam Cc in series. Two kinds of metamorphic coal samples,e. g. ,fat coal and anthracite coal,were select- ed in laboratory,the real part Rs and imaginary part X of complex resistance of coal samples with different water satura- tion (Sw ) were measured,the model fitting was used to obtain the resistance and capacitance parameters and calculate the porosity. The results show that the Resistance-Capacitance model fits well with Rs and X,the model parameters R and C decrease with the increase of Sw ,and the extremum of X-curve with different Sw shifts to the right,has the same physical meaning as the model. The Orthogonal Fracture Resistance-Capacitance model of complex resistance based on the theory of induced polarization and dual-porosity medium has the advantages of clear physical meaning and simple mathematical calculation,the model parameters can predict coal seam porosity. This study lays a theoretical foundation for predicting the water content of coal seam and evaluating the hydraulic fracturing effect by CR.