Study On Propagation Characteristics Of Seismoelectric Waves In The Oil-bearing Reservoir

The study on the seismoelectric effect is of great significance to reveal the mechanisms of the seismoelectric exploration and the electrokinetic logging,while the mathematical model and quantitative simulation of the seismoelectric coupling in oil-bearing reservoirs are presently needed,for promoting the popularization and application of the seismoelectric method.Therefore this article combines the elastic wave theory in the unsaturated porous media and Maxwell's electromagnetic theory,using the electrokinetic coupling theory in oil-bearing reservoirs,in order to establish the mathematical method of describing the seismoelectric coupling waves in the oil-bearing reservoirs.Then the responses of the seismoelectric coupling waves are quantitatively simulated,and the influence of reservoir parameters on the seismoelectric wave responses are analyzed in the oil-bearing reservoirs.The mechanism of seismoelectric coupling is theoretically revealed.First,according to the established elastic wave theory in the unsaturated porous media by other authors,establish the wave equation describing the propagation of the elastic wave in the oil-bearing reservoirs.Quantitatively simulate the propagation characteristics of the elastic wave in the oil-bearing reservoirs,and inquire the influencing factors.Thus the basic elastic wave theory for the further study on the seismoelectric effect in the oil-bearing reservoirs is established.Second,considering the study of the seismoelectric effect in the oil-bearing reservoirs,the established elastic wave theory in the oil-bearing reservoirs and the electrokinetic coupling theory in oil-bearing reservoirs are combined to establish the theoretical model and mathematical method of describing the seismoelectric coupling waves in the oil-bearing reservoirs.The responses of the seismoelectric coupling waves are quantitatively simulated,and the influence of reservoir parameters on the seismoelectric wave responses are analyzed in the oil-bearing reservoirs.Third,the study on the seismoelectric effect is extended to the saturated frozen soil.Consider a three-phase media,including grains,fluid and ice,and combine the elastic wave theory in the frozen porous media and Maxwell's electromagnetic theory,using the electrokinetic coupling theory in the porous media,in order to establish the mathematical method of describing the seismoelectric coupling in the saturated frozen soil.The responses of the seismoelectric coupling waves are quantitatively simulated,and the influences of the porous media parameters such as the porosity and the ice content on the seismoelectric wave responses are analyzed.