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震电效应在地球物理测井和勘探领域拥有十分广阔的前景.为了研究孔隙介质中的震电效应,本文基于毛管模型中渗流场和电流场耦合理论,利用Pride震电理论对震电耦合波传播特性进行了定量模拟;对震电横波、震电快纵波、震电慢纵波的传播速度、衰减常数、电场强度、电流密度以及电荷密度进行了比较,定量分析了其随孔隙度、离子浓度、阳离子交换量的变化规律.分析结果表明:随着频率增大,三种震电耦合波波速、衰减常数以及电流密度与固相速度比值的模值增大,震电横波电场强度与固相速度比值的模值减小,震电快纵波、慢纵波电场模值增大.当频率相同时,震电快纵波波速最大、衰减常数最小,震电慢纵波波速最慢、衰减常数最大,震电横波的波速和衰减常数大小居于快、慢纵波之间;频率不变时,震电慢纵波电场强度与固相速度比值的模值最大,快纵波次之,横波最小;中低频时,震电横波电流密度与固相速度比值的模值略大于慢纵波;高频时,震电慢纵波略大于横波,快纵波一直最小.溶液浓度和阳离子交换量对三种震电波的波速和衰减常数影响很小;溶液浓度越大或阳离子交换量越小,三种震电波电场强度、电流密度与固相速度比值的模值越小,震电快纵波和慢纵波电荷密度与固相速度比值的模值也越小,但是相位几乎都不变.
In order to study the seismic effect in porous media, based on the coupling theory of seepage field and current field in capillary model, this paper makes use of Pride’s theory of electro- The propagation velocity, decay constant, electric field intensity, current density and charge density of the S-wave, the fast P-wave and the slow P-wave are compared and quantitatively analyzed. With the comparison of porosity, ion concentration , Cation exchange capacity.The results show that with the increase of the frequency, the wave velocity, the decay constant and the ratio of the current density to the solid-phase velocity ratio of the three kinds of electro- When the frequency is the same, the maximum longitudinal wave velocity and the minimum attenuation constant are the lowest, the slowest and slowest one, the maximum attenuation constant and the maximum attenuation constant When the frequency is constant, the modulus of the ratio of the electric field strength to the solid-state velocity of the slow electric wave is the largest, and the fast longitudinal wave The frequency of shear wave current density and solid phase velocity ratio is slightly larger than that of slow P-wave at low and medium frequency; the slow P-wave is slightly larger than that of S-wave at high frequency, and the fast P- The effect of the three kinds of shock waves on the velocity and decay constant is small. The larger the solution concentration or the smaller amount of cation exchange, the smaller the modulus of the three kinds of shock electric field intensity, current density and solid phase velocity ratio, And slow compressional charge-to-solid-phase velocity ratio the smaller the modulus, but the phase almost unchanged.