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震电测井方法是以测量(在充满流体的井中)由地震波激发的电场为基础的。在地层内部和地层分界面上会产生两类电磁(EM)场。一种是静止的或局部的电磁波,另一种是辐射电磁波。文中我们利用人造材料或天然岩石制作了各种裂缝性井下模型,并测量了(在充满水的井中)由地震震源激发的电场。实验结果表明,斯通利波在裂缝处产生辐射EM波,它以光速在井孔中传播。并且斯通利波也在井壁上产生电磁驻波。当裂缝的孔径增大时,由于裂缝内离子的密度降低,因而造成震电波振幅下降。与同一井中的声波波形相比,震电波形在确定和表征与井相交的裂缝或裂缝带方面有着更多的优点。
Seismic logging methods are based on measuring the electric field excited by seismic waves (in a fluid-filled well). Two types of electromagnetic (EM) fields are generated at the interface between the formation and the formation. One is static or local electromagnetic waves, and the other is radiated electromagnetic waves. In this paper, we used fractured subsurface models made of artificial or natural rock and measured the electric field that is excited by an earthquake source (in a well filled with water). Experimental results show that the Stoneley wave generates a radiated EM wave at the crack, which propagates through the wellbore at the speed of light. And Stoneley wave electromagnetic wall standing in the well. When the crack diameter increases, the amplitude of the shock wave decreases due to the decrease of the ion density in the crack. Compared with the acoustic waveforms in the same well, the seismic waveforms have more advantages in determining and characterizing the fractures or fractures that intersect the well.