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Looking For Detector Working From 30/50 Metres Distance


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Good afternoon everyone,

I am looking for a long range detector and I would like to know if anyone can design/produce a stand-alone (not hand held) long range detector suitable for detecting gold from a 30-50 metres height.

This is a serious enquiry which foresees the purchase of large quantities of such locators/detectors as well as the development of different detectors for other metals/minerals.

For a better idea of what I am looking for, please see my drawing below.

Thanks,

Law-Italy ( lawrencebon@hotmail.it )

 

590b329eb1c6b_LRLScheme2.thumb.jpg.3dbdf71696dc548843f38c6542d88aa2.jpg

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1 hour ago, Law-Italy said:

I am looking for a long range detector and I would like to know if anyone can design/produce a stand-alone (not hand held) long range detector suitable for detecting gold from a 30-50 metres height.

The short answer is no, there is no such technology to directly detect gold from 30 meters and greater distance, and those who claim they can build a long range locator to do this are lying. That said, there are geophysical devices to detect soil conductivity and resistance, the magnetic characteristics of rock as well as other geologic characteristics that are used by geologists for exploration of mineral deposits on a large scale - many of these are done by flying over the deposit in an airplane, helicopter or by a drone.  So if your goal is finding buried treasure or placer gold deposits, then no, LRLs dont work, if your goal is geophysical exploration for large mineral deposits, then some of this equipment to indirectly detect the characteristics of rocks does exist, but this is probably not a good place to get more detailed information on them. 

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What a concept.  How big would a buried nugget have to be in order to be detected from 175 feet in the air?  

However much tongue in cheek my first question was,  Wouldn't it be neat if you could significantly charge the ground in an area in such a way that surface/shallow metal resonated in some such a way as to be picked up by an overhead sensor?   I mean, we're grinning and nodding and winking at the request but at some level you have to admit that you would think some such activity could be possible. 

Try this on for size.  What if you used an infrared heat sensor/camera and looked at the heat residuals of surface objects at a particular time after sundown or ambient temperature?  Gold would either cool more rapidly or more slowly as compared to the surrounding soil and rock.  It might take a little time to build a background database to compare results to, but I would think that is something that is totally doable.  Combine it with GPS, put it on a drone and fly the grid.  Analyze, and recover. 

HH
Mike

Image result for infrared heat sensors

 

 

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Quote

What if you used an infrared heat sensor/camera and looked at the heat residuals of surface objects at a particular time after sundown or ambient temperature?  Gold would either cool more rapidly or more slowly as compared to the surrounding soil and rock.

It might work if most gold was on the surface exposed to the sunlight, but even a quarter inch of dirt would hide them. Unfortunately, most gold is buried at least a little. If you put a quarter inch thick wood panel in front of the people in the picture above, the people would disappear, and you'd see only the wood panel.

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Just need a few big ones to pay off. 

HH
Mike

 

Image result for thermal imaging landscape pictures

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5 hours ago, klunker said:

 What is it that you are trying to locate?

You hit the nail on the head Norm. Long Range Locators or LRL tends to refer to a certain class of "belief based" treasure hunting device. Yet as Chris notes there are many "science based" devices that work at greater distances than are the norm in the hand held metal detectors that we usually discuss here on the forum. These fall under a class I refer to as "geophysical prospecting devices" used in exploration geophysics. From Wikipedia:

"Exploration geophysics is an applied branch of geophysics, which uses physical methods, such as seismic, gravitational, magnetic, electrical and electromagnetic at the surface of the Earth to measure the physical properties of the subsurface, along with the anomalies in those properties."

This 1995 paper from the U.S.G.S. briefly summaries the state of the art in table form with range to target in the column on the right. Click on image for larger version.

IMG_0387.PNG

The classic problem is the same as what we face with hand held metal detectors. Small items can only be detected at relatively short distances, and larger items at greater distances. For example, a small gold nugget weighing under a gram might be detectable at one centimeter, whereas a gold nugget weighing several kilograms might be detected at one meter. In order to achieve detection depths exceeding a meter, the target has to be extremely large, so large that no single mass of gold exists that could be detected at that range.

In the realm of science based treasure hunting devices two well proven detectors are the Fisher Gemini 3 and White's TM808. The TM808 chart does a good job of showing how large items have to be to be detected at realistically achievable depths using existing technology:

whites-tm-808.jpg

If you are looking for a gold nugget the size of a compact car, it might be detected at 20 feet / 6 meters. I think we can all agree that is unlikely. Nuggets the size of a one gallon can do exist, and these might be detected as deep as 1.7 meters depending on their shape and orientation in the ground. This would be possible with devices such as the Minelab GPX 5000 with a very large coil or even the TM808 in milder ground conditions.

Geophysical prospecting methods rely on the targets being far larger than any single gold nugget. A typical target might be a mineralized zone in the earth a kilometer in diameter. This makes geophysical prospecting devices other than standard metal detectors as discussed on this forum inapplicable for use when looking for items smaller than a one gallon can. People often mention ground radar, and the same issue exists. The distance to target or target resolution is tied to the size of the item sought, and the greater the range you wish to detect it, the larger the target must be. That is the science of it as we currently know it, and devices that claim to exceed this limitation are stepping outside the realm of known science at this time. My advice to everyone always is stick with known provable scientific methods and avoid items sold using pseudoscientific marketing.

Geotech LRL Resource

Gold From Water (and Other Mining Scams) Nevada Bureau of Mines and Geology Special Publication #22

HANDBOOK OF GEOPHYSICAL PROSPECTING METHODS FOR THE ALASKAN PROSPECTOR

A REFERENCE FOR GEOPHYSICAL TECHNIQUES AND APPLICATIONS

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This reminds me of a Discovery Show!  I'll make it a separate thread.

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LRL's are scams (and I believe the manufacturers should be criminally prosecuted as such), but the idea of long distance detection is not beyond the realm of scientific reality.

Magnetic fields decay to infinity, so technically you could detect a nugget at infinity with the right set of conditions, equipment, and an infinite amount of time to listen for the signal to return. Physically, long distance detection is not impossible and it's not so much a distance problem (we can pick up signals from trillions of miles away with radio telescopes, we can detect weak signals like cosmic background radiation, etc) - but a noise problem and attenuation problem.

If you lower the noise floor enough you can hear anything. If you decrease the attenuation enough, you can hear anything. Ground causes attenuation far more than air at most frequencies of interest. We are interested in buried objects. And we live on Earth, the planet with the busiest (known) airwaves in the universe. 

Noise is something we can work on, the ground is sorta a big limitation right now with conventional detectors but I believe there are solutions to both that are better than what we have now, just different than what people would consider a "metal detector".

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