Downward Continuation Method Using Equivalent Source Technique with Full-Parameter Joint Estimation

To address accuracy limitations in equivalent source-based downward continuation arising from fixed equivalent source positioning, a novel magnetic field continuation technique dynamically optimizing equivalent source parameters is proposed. Traditional approaches utilizing predefined subsurface equivalent source configurations exhibit inherent deviations from geological realities, resulting in substantial errors during deep magnetic field characterization. In contrast, simultaneous three-dimensional dynamic optimization of both equivalent source positions and magnetic moments yields enhanced structural congruence with geological formations. Simulation results demonstrate that the proposed method improves the continuation accuracy by more than one order of magnitude compared to the single-layer and multi-layer fixed-source methods. This advancement provides enhanced precision for critical applications including deep-sea mineral exploration, crustal fault identification, and geomagnetic navigation systems.