Highly unlikely you think
well Ive just bought and avalanche tranceiver for my forthcoming snowboard holiday (quivers with excitement :P ). It can locate another tranceiver - giving direction and distance - up to 40 meters.
Who reckons this may work underground ( i.e for radio locating).
I need to know more about the gubbins to asses whether this would work through rock but in some instances ( eg the snakes pyjamas/taylors way connection, bagshawe) it would come in for distance determination.
if it isnt powerfull enough to work through rock - you could possibly create a powerfull emitter that replicates the pulse from an AT and use the AT to track the signal.
Ps - cant believe caves.org.uk blocked blubbas advert for this site! :roll: