Abstract:

In order to fulfill the observation requirements for the total magnetic field intensity of geomagnetic stations, a specialized magnetometer architecture is independently designed for the stations, and the Overhauser magnetometer is developed for station monitoring. Sensitivity evaluations are conducted using both single-station direct measurement and dual-station synchronized methods under field conditions with low noise and in environments with high electromagnetic interference. The experimental results from both direct measurement and synchronized methods indicate that the sensitivity of the JOM-5J magnetometer can reach 0. 02 nT at a 1s period. It is capable of replacing the GSM-90F for applications in earthquake precursor observations and long-term

volcano monitoring.

Key words: seismograph station, Overhauser magnetometer, RS485 communication, sensitivity