The source is located 2000 meters from the center of the inhomogeneity. The x, y and z components of the anomalous magnetic field have been simulated at nine receiver points arranged on a homogeneous grid. The inverted area is a homogeneous mesh consisting of 6 X 6 X 6 cubic cells surrounding the anomalous structure to be inverted. The vertical slices of the inverted area and the true model are presented in Figure 2. Vertical cross-sections of the inverted area and the true model for Model 1.
Dotted lines mark the discretization of the inverted area.
The data vector consists of 135 simulated field components. The synthetic data is generated by a full integral equation code and it has been contaminated by 3 percent random noise. The model parameters are the unknown anomalous conductivity values of each cell of the inverted area. The inversion problem is ill posed and underdetermined, so we used the regularized conjugate gradient method. The results of QA inversions are shown in Figure 3.