Abstract:

In order to investigate the response of borehole radar to metal ore, finite difference time domain (FDTD) was applied to borehole radar forward modeling on metal ore detection. Numerous simulated results were obtained for different metal ore-body, such as spherical, planar, and a practical ore-body. Spherical ore-body exhibits hyperbolic curves in profile and exact position can be determined after migration processing. As the planar ore-body is penetrated by the borehole, direct wave is shifted and weakened, andreflection events extend upward and downward. However, when it is not penetrated by the borehole, reflection exhibits a linear characteristic. For the practical ore-body, different boreholes show different signal characters. Combing with the detection from three boreholes, we can deduce the shape of the ore-body, and judge that the ore-body has the characteristic of low-resistivity and high permittivity.

Key words: borehole radar, metal ore, numerical simulations, finite difference time domain