2D sequential inversion of total magnitude and total magnetic anomaly data affected by remanent magnetization

ABSTRACTRemanent magnetization complicates the inversion of magnetic data due to altering the strength and direction of the magnetization vector. To deal with the problem, we have developed a 2D sequential inversion method of successively recovering the distributions of magnetization intensity and susceptibility and estimating the magnetization direction. The magnetization intensity distribution is first recovered from the total magnitude anomaly that is frequently transformed from the observed total-field anomaly and is invariant with the magnetization direction. With the recovered magnetization intensity distribution, we forward model the total-field anomalies caused by sources with different magnetization directions and calculate the correlations between the observed and predicted data. The orientation when the correlations attain a peak of maximum is defined as the optimal magnetization direction. Finally, the estimated magnetization direction helps to recover the susceptibility distribution by furthe...