Detection and identification of a tunnel by iterative inversion from cross-borehole CW measurements

Abstract

Iterative multiparameter optimization is applied to find underground geophysical structural parameters including an isolated penetrable target such as the air tunnel. 11 physical parameters such as relative permittivities, and the conductivities of the background, the tunnel, and the fractured zone, their sizes and locations, and the measuring borehole distance are found from the in situ measured data by using the hybrid optimization algorithm combining the Levenberg–Marquardt and the genetic algorithms. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 21: 458–465, 1999.