摘要
The error and estimation formula of approximating total magnetic field anomaly ΔT as harmonic field is discussed in this paper.It shows that the error is positively correlated with modulus Ta of magnetic anomaly strength as well as the direction change value ψ of normal magnetic field strength T0.In contrast,the error is negatively correlated with the modulus T0 of normal magnetic field strength.Tests find that the error reaches the maximum when the angle θ between magnetic anomaly strength Ta and normal magnetic field strength T0 closes to π/2 or 3π/2.According to characteristics of the work area magnetic field,the estimation of the error of approximating total magnetic field anomaly ΔT considering as harmonic field using the error estimation formula,can reasonably determine the precision of magnetic survey data interpretation and magnetic survey,and it avoids "excessive" data interpretation and "virtual high" precision of magnetic survey.It has great practical value in the high-precision magnetic survey.