[meteorite-list] Ground penetrating radar at Carancas?

[Piper R.W. Hollier]

Hello again list,

Ground penetrating radar (GPR) is commonly used for non-destructive 
investigation of archaeological sites. GPR "can detect objects, changes in 
material, and voids and cracks." (Wikipedia) Has anyone thought of mapping 
the crater with GPR before sending in a backhoe to rip it open? This could 
be one way to have some idea whether there are meteorite masses under the 
ground, how large, and where, before starting to dig. It could also yield 
valuable information about the morphology of the crater, with potentially 
more precision and detail than digging would allow.

Can someone on the list comment on the state of the art of GPR? How deep 
can it penetrate nowadays? (Wikipedia says 15 meters, best case.) Would a 
high water table be a problem? (Wikipedia says that range would be greatly 
reduced in "moist and/or clay laden soils.") Are there new designs or 
techniques that could get around such limitations?

In any case, there would be some thorny practical problems to be dealt 
with. Ordinarily the antennas need to be nearly in direct contact with the 
ground, which would seemingly make it very difficult, if not impossible, to 
do a scan of an area where the ground surface is anything but flat. Or has 
someone come up with a "workaround" for this issue in a similar situation?

Best wishes to all,

Piper