Development and performance tests of maintenance-free ultra-low noise solid nonpolarizing electrodes
WANG Hui1,2(), FU Shu-Ji2, GE Shuai-Yin2, MA Fang-Yuan2, SONG Bao-Jia2, LUO Jing-Cheng3
1. State Key Laboratory of Coal Resources and Safe Mining, China University of Mining & Technology, Beijing 100083, China 2. School of Earth Science and Surveying Engineering, China University of Mining & Technology, Beijing 100083, China 3. General Exploration and Research Institute of China General Administration of Coal Geology, Beijing 100039, China
To overcome the shortcomings of traditional nonpolarizing electrodes, such as the poor stability of potential difference, high low-frequency noise, short life, and requiring regular maintenance, the authors researched and developed maintenance-free ultra-low noise Pb-PbCl2 nonpolarizing electrodes after over a decade of development and constant tests. Lab test results show that the new nonpolarizing electrodes have a potential difference drift within one month of less than ±0.06 mV and a temperature coefficient of less than 20 μV/℃, which are 5% and less than one-fifth of those of the PMS9000 electrodes exported from France, respectively; under the ideal condition of the distance between two adjacent electrodes of 100 m, the signal-to-noise ratios relative to the natural induced electric field are 40dB@103s, 20dB@104s, and 10dB@105s. The field comparative tests show that the newly developed solid nonpolarizing electrodes can significantly improve the acquisition accuracy of geoelectric field signals and the data quality of dead and low magnetotelluric frequency bands.
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WANG Hui, FU Shu-Ji, GE Shuai-Yin, MA Fang-Yuan, SONG Bao-Jia, LUO Jing-Cheng. Development and performance tests of maintenance-free ultra-low noise solid nonpolarizing electrodes. Geophysical and Geochemical Exploration, 2022, 46(3): 714-721.
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