Particle Swarm Optimization Method for Stochastic Inversion of MTEM Data

An improved implementation workflow for centered-centered progressive particle swarm optimization (CCPSO) inversion technique with stabilizing functional, irregular CCPSO (IRCCPSO), for successful prospecting of subsurface resources using multitransient electromagnetic method (MTEM) was introduced in this letter. The stabilizing functional was used to introduce constraint in the inversion algorithm; thus, the global best position was updated using multiobjective functional. The regularization parameters used were selected from L-curve that best minimizes the global solution. Comparison between the results obtained from IRCCPSO, general centered-regressive PSO (RGPSO) and irregular RGPSO (IRGPSO inversion techniques was used to establish the effectiveness of the new work flow. Furthermore, pseudo2-D inversion study over a buried resistive body model was carried out using a limited amount of search space. Last, 2-D inversion was carried out using the common offset method. The obtained inversion results were a good representation of the earth model. Consequently, this confirms the effectiveness of the IRCCPSO technique as a good geophysical tool for MTEM inversion using a limited search space.