Earth resistivity survey to find buried objects

[Gunslinger44]

The "objects" in this case being a cache. My question,for those more familiar with ERMs, is what size does an object have to be for a resistivity meter to pick it up?
Another question, I have read that the depth of survey is half the distance between the electrodes in the ground. Assuming this is true, and you wanted to search down to a depth of 5 feet, would the meter also pick up objects buried at 1, w
2, 3 feet, etc? Also, what is the width of the survey per electrode station?

[homefire]

ERM is not the best tool in the shed for Cache hunting. Unless the Item is quite sizable I don't think you would have a chance using one.

Width of Detection again would depend on target size and make up.

[Gunslinger44]

Thank you very much, this is exactly what I needed to know

[homefire]

A decent PI machine would be my weapon of choice.

[Gunslinger44]

A decent PI machine would be my weapon of choice.

Absolutely, thats why I'm here just took a Whites TM 800 up,but wasn't getting anywhere near the depth it says on test target,deep seeking PI it is

[smartmax]

this cave image created with OhmMagic

[EstebanM]

A decent PI machine would be my weapon of choice.

What's the best bang for the buck PI machine these days?

[AK48]

interesting thread , dear homefire , you says " ERM is not the best tool in the shed for Cache


hunting " but we know arch?ologists use this kind of tools to discover what is down with good


accuracy , you know i was gonna buy one so explain me what's going wrong with this tool


knowing that in my country items are far down until ten meters , and this way i've selected few


tools but i've no decided yet which one will be the best for me
1 / pro accumeter series from accurate locator
2 / quattroforce , accumaster pro digital and pro accumaster VII from GDI
so i want you to give me advice if i buy or no , thank you
regards

[Bhathu saaii]

interesting thread , dear homefire , you says " ERM is not the best tool in the shed for Cache


hunting " but we know arch?ologists use this kind of tools to discover what is down with good


accuracy , you know i was gonna buy one so explain me what's going wrong with this tool


knowing that in my country items are far down until ten meters , and this way i've selected few


tools but i've no decided yet which one will be the best for me
1 / pro accumeter series from accurate locator
2 / quattroforce , accumaster pro digital and pro accumaster VII from GDI
so i want you to give me advice if i buy or no , thank you
regards

Accumeter is the best..tested here in the philippines

[AK48]

hello ! wich brand is tested in philippines ?

[Carl-NC]

It is possible to find buried caches with an ERM. But you will need a real 4-probe ERM with mapping software, and a lot of patience. The Accumeter is a piece of garbage, it's a $25 toy pretending to be a serious instrument.

[AK48]

thanks Carl but if you think accumeter is a piece of garbage and a toy , which is a serious one to buy

[Carl-NC]

What you want is a true 4-probe meter that can do Wenner-type measurements (or Schlumberger), has AC constant-current injection, and also has data-logging and mapping software. I don't have direct experience with any particular devices but I do own an Accumeter and it is a useless toy (same for Kellyco's GPL units).

Here are a few links if you want to see what a real ERM device looks like:

https://www.agiusa.com/supersting-wifi

https://www.aemc.com/products/ground-testers

http://www.geonics.com/html/conductivitymeters.html <--induction-based ERM

https://www.globalgilson.com/soil-resistance-meters