| Seismic effects is a phenomena of transformation of energy in rocks, that is the interaction between elastic wave field and electromagnetic in the medium of the porosity, and the medium caused these two kinds of geophysical field changes of physical effects. It is a special physical phenomenon in the gap medium, and this kind of phenomenon is relevant to the seepage. Under the effect of electric shock waves and electromagnetic wave amplitude and frequency of seismic waves with related not only, and the medium reservoir porosity and permeability of reservoir fluid properties, such parameters closely linked, so using seismic effects can determine pore strata of the cut-off frequency, reflect the earth medium elasticity parameters and electrical parameters, etc. With the increasingly seismic effects study, its application has been paid much more attention in the oil vapor industrial fields, major western oil companies; logging companies are being hard in studying the practical seismic exploration and electricity.For many years, the acoustic logging has been developing rapidly, but the general way of acoustic logging is to put the sound and geophone together in the water-hole surveys, it has great limitation in detecting the far wells strata. And although the detection range of earthquake is large, it can not give us the detailed description about the strata; therefore cross well seismic ground is one of the ways to make up the shortcomings for acoustic logging and earthquake. Its essence is measured by reservoir formation characteristics between Wells and horizontal well logging, to compensate for insufficient detecting ability, and to solve the problems of borehole Wells and collecting information and information abundance, etc. Shake well under the effect of sound source within the field of study, but for more work, sound intercultural hole well placed in the formation of pore acoustic field characteristics and laws, is not comprehensive.Based on the actual situation of physical model is established, from the strict wave theory and electromagnetic theory to solute and calculate the electric field in the acoustic radiation and dissemination, making further studies in the field of acoustic propagation law and the spread of the sound field coupling, and the influence of porosity stratigraphic parameters, it has significant meaning to improve the logging interpretation, better understanding and to improve the actual logging theory and method.The passage from the frequency domain Biot theory and growing elastic wave, electromagnetic coupling equations Under the effects of electric shock, the vertical Wells at the sound source in the field. According to the theory, using the Biot growing equat ions, porous media acoustic power coupling problem transformed into solving equations of the scalar wave number and vector Helmholtz equation and using porous skeleton of the displacement of the formation and Z = 0) on the plane of boundary condition, can the backlog of constant containing the direct sound field, empathy, through the wall boundary conditions of the inside and outside could gain the's sound field backlog constants, According to the dual Fourier transform can gain time and space domain of internal and external acoustic field expression, then through MATLAB, analyze the numerical simulation and images.In numerical simulation process, in order to facilitate understanding and comparison, we follow from near the source, frequency from high to low order, we start from high contents of near the source of the wave numerical simulation and analysis, that is the source of the lateral wall close. When the sound is 1000 magnitude of parma,it can receive several mill volt electric field, and simultaneously it takes more investigation, sound waves can be observed P waves, bend, the wave, and the stone table. At the same time, the electric field, magnetic field Ez Er can be seen in the H theta, accompanied with longitudinal waves, with bent, and with the stone table waves. At the same time, the magnetic field Ez H theta can see electromagnetic wave. Compared P with electric pressure, it can see the conversion efficiency Ez the relation of longitudinal waves, each of them is the maximum and the minimum. While in a sound that is P, electric Ez and transformation of tip of guiding status, electric, magnetic dipole H theta is dominant. High contents, far away from the source, the sound wave in the P, stone as the source of change since the attenuation distance to the source, When the source is reached a certain distance, it only observed shear wave, electromagnetic and corresponding also can only be observed with p-wave and shear with. Far from presenting high at the source of the sound extremely investigation found that shear wave and P ,the electric wave and the longitudinal and accompanied with Ez s-wave mainly unipolar stimulate and transformation, the electric field, magnetic field in the H theta Er with p-wave and shear is mainly with dipole and forwarding.We consider the situation of the low pressure far away from the main source, when to pat, it is acceptable to the magnitude of the magnitude of several mill volt electric field. When the investigation, acoustic multiple, magnetic, electric P H theta EHz information is mainly the curve and transformation, tip and electric dipole and Err is transformed, To well received in the acoustic field by changes in the distance from the source, along with the increase of the electric field, the sound wave and transverse shear wave and accompanied with or smaller, Examine the influence from receiving, with pressure from receiving increasing P and has reduced, and electric EHz first. The formation parameters for gas and geology investigation research has important significance, so also emphasizes the formation parameters on hard strata and well received in the sound field. The longitudinal and transverse odium P soft hard strata formation higher amplitude, and electric field, magnetic field, Err EHz in longitudinal and H theta accompanied with shear change rule, on the contrary, the variation of the same with hard strata. We found the dipole bend over stone motivated by quad intensity of porosity, and stone with the wave of porosity and maximum shear wave attenuation, and with p-wave and shear and accompanied by its relatively smaller effect. With the increase of the pressure of permeability and shear wave amplitude P increases, and electric field, magnetic field, Err EHz H theta variation in contrast, the impact of bending on sound pressure P almost very small, and electric field, magnetic field, Err EHz H theta will reduce as curvature increases. Almost no influence on acoustic mineralization and electric field, but magnetic field, Err EHz with increase of salinity H theta obviously.Aiming at the Biot medium well point source integrate the sound field, this passage does some theoretical research on numerical simulation under the background of cross-well seismic, which makes us have a better understanding of sound electrical field cross-well seismic Also, it will benefit the interpretation of taking good advantage of acoustoelectric effect on the oil well, which reflect the creative of our research.
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