Detecting on wet ground????

Hi All
With the wet season approaching in North Queensland, I have a question about detecting after it rains when the ground has a high moisture content.
Does the wet ground affect the capabilities of a detector? does it enhance the affect of mineralisation?
does it affect the HALO effect of gold ?
Are mono coils or dd coils better after rain?
Please bear in mind I am using an SD2200d if this makes any difference.
thanks all
Lee

Hi Lee,
I seem to recall a discussion about this previously on this forum with a mention of the conductivity of the soil being affected hence an effect on depth/sensitivity.

From a practical point of view I have noticed that when it rains heavy enough that the ground is saturated & there is water present on the ground surface, then it appears to me that there is less depth/sensitivity than on the same ground when it is dry. However, when the water soaks in further (after a couple of days) I've noticed the opposite where there is a marked improvement in depth & I'm suddenly pulling deep nuggets out of previously flogged ground

My observations have been with the GP3500 & the GPX series detectors all with mono coils. It would be interesting to hear what others have experienced.
Cheers, Andy

As Andy has mentioned, there's believed to be an enhancement to the depth of the coil penetration... possibly by up to 20%... in damp soil. If the soil is actually quite wet, you may see a reduction in performance and many people will avoid detecting in recent heavy rains for this reason.

Best results seem to be had after several hours or even a day after a light shower. Quite a few prospectors claim better depth and sensitivity in moist soil after rains. I believe the moisture may allow for more conductivity towards metals deeper down that otherwise might be missed.

It's not confirmed by any means but enough people claim it gives them an advantage in hammered ground. I do recall one chap who said his 4500 was howling non-stop but then explained to me that it was pouring rain and he was detecting in a few centimeters of water. So too much water will dissipate the charge from the coil and moist soil (not too wet) will possibly enhance the depth.

Cheers,

Marco

Well maybe better peno but with that comes grd noise.

nero_design wrote:As Andy has mentioned, there's believed to be an enhancement to the depth of the coil penetration... possibly by up to 20%... in damp soil. If the soil is actually quite wet, you may see a reduction in performance and many people will avoid detecting in recent heavy rains for this reason.

Best results seem to be had after several hours or even a day after a light shower. Quite a few prospectors claim better depth and sensitivity in moist soil after rains. I believe the moisture may allow for more conductivity towards metals deeper down that otherwise might be missed.

It's not confirmed by any means but enough people claim it gives them an advantage in hammered ground. I do recall one chap who said his 4500 was howling non-stop but then explained to me that it was pouring rain and he was detecting in a few centimeters of water. So too much water will dissipate the charge from the coil and moist soil (not too wet) will possibly enhance the depth.

Cheers,

Marco

please explain? ie: Excalibur, beach snoop etc etc...

Every detector I have ever owned has performed better on wet ground whether it be just a bit wet or under a foot or two of water and where the water has had time to soak in produces best results for deep targets.

Not sure why the 4500 would be noisy on wet ground, must be the nature of the pulse and the timings.

My Infinium thrives on wet ground, the wetter the better, salt or fresh and in the gold fields it purs along nicely over wet ironstone or whatever. This machine while not as hot as the 4500 will still find 0.1gm nuggs and up in wet or dry ground and I have yet to find mineralisation where the Infinium was unusable.

This is not a plug for the garrett, I call it as I see it. I have my MLs and they are great.

Adrian SS

Adrian SS wrote:Every detector I have ever owned has performed better on wet ground whether it be just a bit wet or under a foot or two of water and where the water has had time to soak in produces best results for deep targets.
Adrian SS

Hi Adrian,
So does that include VLF's as well? Be interesting to know if it's a PI phenomena only.
Cheers Andy

Yep. VLFs, PIs, BFOs, TR Discims,everything.
I think the effect is more pronounced with PIs, although my SOV is a VLF and it goes real deep in wet ground although if you look at the signal from a SOV you will see that it is not a simple VLF Sinewave.

With VLFs the frequency has a lot to do with it; low frequencies can be made to ground balance well whereas high frequencies are difficult to balance . PIs run at low pps compared to VLF sine waves. The pulsed square waves from PIs are processed in a vastly different way to VLF sigs which enables large deep target detection in all types of ground but, as with VLFs, the higher the PPS/frequency (up to a point) the more likely the detector is to respond to wet and mineralised ground.

Personally I find moist, (not wet) ground, makes it easier to run a small mono over quite hot ground, or I should say, ground I was not able to go over with my 3500 when dry.

Hi there Lee;

I have used my 2200d here in Victoria only,both in wet and moist conditions,using both DD and mono coils.
I can tell you this that,in very wet or highly saturated conditions,the detector coil/combination become a little louder and a bit more noisier,than when the ground conditions were slightly saturated or slightly moist.
Slightly more noise with monos than with DDs..Halo around targets also enhance and seem to become broader. As for depth,best depth i've ever achieved was in slightly moist ground.Now,that's not to say that the machine wasn't getting the same or even greater depth in highly wet conditions,it's just that the extra ground noise might have been drowning out very faint deep target signals.The only real way to find out which gives you the best signal to depth ratio is to go over a known original buried target during the wet and then moist conditions, which maintains the original halo around the target as well.


Happy Prospecting.