Detection of Deeply Located Dormant Tunnel Using Cross-Borehole Radar

Abstract

In process of analyzing the cross-borehole frequency-swept radar signatures of an intrusive tunnel in the past, one of serious difficulties was the effect on the oblique angle of the tunnel penetrating between a borehole pair. First, the horizontal deviation of three boreholes is reviewed in detail. And our recent studies on the cross-borehole pulse radar signatures of an obliquely penetrating tunnel are presented here.