Analysis on Systematic Errors of Aeromagnetic Compensation Caused by Measurement Uncertainties of Three-Axis Magnetometers

Abstract

Aeromagnetic surveys are important in geophysical prospecting and magnetic anomaly detection. Magnetic fields are typically measured by optically pumped magnetometers (OPMs) mounted on an aircraft. Platform-generated magnetic interference severely compromises the sensitivity of the OPMs. Therefore, aeromagnetic compensation is necessary. However, measurement uncertainties of three-axis magnetometers influence the qualities of aeromagnetic compensation and there is no method that can directly predict the qualities of aeromagnetic compensation before calibration flights. To address this issue, we propose a method to calculate the systematic errors of aeromagnetic compensation caused by measurement uncertainties of three-axis magnetometers and analyze the performance of aeromagnetic compensation in advance of calibration flights. It can be used to estimate the residual errors of aeromagnetic compensation theoretically. Using this method, researchers can assess whether aircraft platforms are appropriate to implement aeromagnetic surveys or not before carrying out experiments in practice. Field experiments are carried out to exhibit how to use the method to calculate the measurement uncertainties of aeromagnetic compensation in different conditions. The results of the experiments demonstrate the validity of the method.