don lancaster on gpr (1995)

[Elie]

http://tinaja.com/glib/ratholes.pdf

Subsurface radar –

It is extremely difficult to couple any
electromagnetic signal in to or out of the ground. Firstoff
because of direct losses. Second because of severe coupling
mismatch at the earth-air interface. And third because
water has an enormously high dielectric constant. As a
result, your effective ranges will always be ridiculously
shorter than you’d first suspect.
Any "treasure finder" that claims a penetration greater
than its length or whose resolution is less than one-tenth
its sensor head size is highly suspect.

(at end of first page)


What does everyone think, and how have developments since this was written affected opinions of the practicality of good gpr?

[Seeker]

http://tinaja.com/glib/ratholes.pdf

Subsurface radar – It is extremely difficult to couple any
electromagnetic signal in to or out of the ground. Firstoff
because of direct losses. Second because of severe coupling
mismatch at the earth-air interface. And third because
water has an enormously high dielectric constant. As a
result, your effective ranges will always be ridiculously
shorter than you’d first suspect.
Any "treasure finder" that claims a penetration greater
than its length or whose resolution is less is highly suspect.

(at end of first page)

What does everyone think, and how have developments since this was written affected opinions of the practicality of good gpr?

Hi ,
I think that Don Lancaster was carried away a bit. If he is right , a half of units around us do not work! In fact when Mr. J.Watt made first engine, some people predict that engine never will be used, becouse coefficient of performance was less then 2 % and it was very heavy!
So , GPR work and can find things little "then one-tenth of sensor head" !
One of the reasons is EM-field speed in ground is less then in air.

This man (Don Lancaster) read and wrote more then build or experiment with something. May be he is professor of philosophy?