Research On Deep Well Potential Measuring Device Based On New Electrode

Deep-well observation is as important as surface(sea surface)observation,aerial telemetry and remote sensing as well as seabed observation.It is also an important means to solve the problems of deep resource exploration and geological disaster prevention.Deep well observation can not only avoid all kinds of electromagnetic interference on the surface,but also measure the vertical component of the earth electric field,which is more conducive to the observation of weak signals in the depth and the improvement of signal-to-noise ratio.The measurement of long period electric field in deep Wells is of great significance for monitoring the electrical changes in the deep earth.However,due to the high temperature,high pressure,acid corrosion and water vapor in deep Wells,conventional instruments and equipment cannot work normally.For this reason,combined with the practical requirements and difficulties of deep well measurement,a deep well electric field measurement device based on a new type of electrode was designed.The research and design of deep well electrode and signal acquisition system are included.Mainly completed the following content:(1)The research and technical development status of deep well survey and natural electric field survey at home and abroad were reviewed and summarized;(2)The influence of high temperature,high pressure and acid corrosion environment on the polarization potential of deep Wells was studied and analyzed;(3)The electrode fabrication materials suitable for the deep well environment were selected through a large number of reference materials,and the solid non-polarizing electrode suitable for the deep well electric field measurement was studied and made according to the two sets of plans simultaneously,and the method and device for installing the electrode in the deep well were designed;(4)According to the characteristics of deep well environment and the requirements of electric field measurement,the overall scheme of the signal acquisition system is designed.The circuit core devices are selected according to the requirements of temperature resistance grade and index.The relevant circuits of the signal acquisition system are designed according to the basic requirements of high temperature resistance,high sensitivity,low noise and low power consumption;(5)the basic indicators of electrodes were continuously tested in high temperature and corrosion environment.Due to the difficulty in purchasing high-temperature devices,it was impossible to build actual circuits.Therefore,only simulation experiments were conducted on the signal acquisition system.Through the experimental test,it is concluded that the electrode meets the expected basic indexes,with stable performance,corrosion resistance and high temperature resistance.At the same time,the simulation experiment verifies the noise reduction level of the measurement system.