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A VHF impulse radar system operating on the ground is a viable technique for mapping the near‐surface geological structure and electrical properties of permafrost. A fixed antenna configuration transported over the surface yields a reconnaissance map of two‐way travel times for subsurface reflectors. Wide‐angle reflection and refraction (WARR) sounding determines propagation velocity versus depth when performed in layered areas. To obtain a WARR sounding, one measures travel time versus antenna separation. These techniques were field tested in the Tuktoyaktuk region of the Mackenzie River delta, N.W.T. Data recording was on a graphic display for initial field analysis and on analog magnetic tape for subsequent processing. Reconnaissance surveying has mapped structural features at various depths between 3 and 30 m. The electrical loss of the soils at a site limits the penetration depth. Clays and silts …