collapse


* User Info

 
 
Welcome, Guest. Please login or register.
Did you miss your activation email?

* Who's Online

bcgoldjunkyLanny

Dot Guests: 260 | Dot Users
Dot Hidden: 0

* Board Stats

  • stats Total Members: 13054
  • stats Total Posts: 131628
  • stats Total Topics: 18400
  • stats Total Categories: 5
  • stats Total Boards: 48
  • stats Most Online: 814

* Advertisers

Mining Claims
Gear Pan
The lil Gold Spinner
BC GOLD
The lil Gold Spinner
The Pocket Sluice

Author Topic: Testing  (Read 161 times)

0 Members and 1 Guest are viewing this topic.

Offline steve 009

  • Full Member
  • ****
  • Posts: 90
  • Kudos: 4
Testing
« on: January 13, 2020, 11:34:03 AM »
Good Morning Everyone i just watched a recent Gold Rush show and Rick Ness had a company out to find low spots in the Bedrock under all the over burden ,they said this teck has been around for along time. They called ita Resasity Tester or something like that ,i tried every spelling i could think of but i am having no luck in looking it up. Anybody happen to know how to spell it  Thanks Steve

Offline JOE S (INDY)

  • PPT Invited
  • *****
  • Posts: 1346
  • Province/State: Trapper Creek, Alaska with Winters in Idaho
  • Country: us
  • Kudos: 84
  • Moderator
Re: Testing
« Reply #1 on: January 13, 2020, 12:34:55 PM »
I can't say for sure -- but -- did you try "Resistivity Testing"   -   measuring / mapping the ground's electrical resistance?  If low areas contain more moisture (?) then the resistance to current flow might give some clues when compared to other areas. 

If black sands (or some other mineral) are more electrically conductive than other 'stuff' nearby then that could be a clue, too.   

<-dont~know->        <-thinking->         <-hypnotized->

Could that be what you are looking for?   <-idea->

https://search.yahoo.com/yhs/search?hspart=sz&hsimp=yhs-001&type=type7089952-sv7-101-9249&param1=101&p=Resistivity+maping&param2=9249

https://search.yahoo.com/yhs/search?hspart=sz&hsimp=yhs-001&type=type7089952-sv7-101-9249&param1=101&p=Resistivity+testing&param2=9249

Joe
Wiser Mining Through Endless Personal Mistakes

Offline steve 009

  • Full Member
  • ****
  • Posts: 90
  • Kudos: 4
Re: Testing
« Reply #2 on: January 13, 2020, 12:41:07 PM »
Good Morning Joe yes i think that was what they where using Thank you so much for your help ,I will do some searching to see how much they cost . Thanks Steve

Offline JOE S (INDY)

  • PPT Invited
  • *****
  • Posts: 1346
  • Province/State: Trapper Creek, Alaska with Winters in Idaho
  • Country: us
  • Kudos: 84
  • Moderator
Re: Testing
« Reply #3 on: January 13, 2020, 12:53:04 PM »
Steve,

That's gonna cost you!   <~ShOcK~>   lol!!!@*

You're going to have to let us know if it worked out for you or not.   Not the big $ info - just was it successful in finding low pockets in bedrock.  A little info on HOW it works might help other folks here, as well.   [-1st-]

 We just don't hear enough about this sort of thing and "Inquiring Minds Want to Know!"

Best of luck!

Joe
Wiser Mining Through Endless Personal Mistakes

Offline mulletator

  • PPT Invited
  • *****
  • Posts: 45
  • Country: 00
  • Kudos: 7
Re: Testing
« Reply #4 on: January 13, 2020, 04:51:28 PM »
Resistivity has been used a lot in the Yukon.  Other techniques are GPR (ground penetrating radar) and seismic.

Resistivity works by placing a series of electrodes along a line with equal spacing.  Then you inject electricity from a generator into the ground.  You measure the amount of resistance in the ground between electrodes.  The depth is interpreted by the change between gravel and bedrock resistivities.

GPR shoots a radio signal into the ground and measures how long it takes to bounce off the rock/gravel layers below.  In a perfect world, it would work OK but there are many variables that can skew the data.

Traditional seismic works in a similar way to GPR but uses actual ground vibration.  You typically have vibration recorders called geophones set up in an array to record the bounces from the source.  You typically blow off some dynamite and measure the time it takes for the energy to bounce of each layer and bedrock.

I have used all of the above and tested them with drill results.

GPR doesn't work very well.  It is very susceptible to groundwater or clays which will give false bedrock readings.

Resistivity/IP also has drawbacks for things like groundwater and permafrost.  As well as the need to run long electrical lines and have a crew on hand.  If there are highly conductive gravels or bedrock it skews the data too.

Seismic is the best option for bedrock profiling.  I actually have my own seismic system and have been using it since the summer of 2019.  The system that I am using is a passive seismic system that doesn't require dynamite or cut lines.  It's a new system and it works awesome and happens to be the least expensive.

This is the best way to map bedrock.  It doesn't matter if the ground is frozen or has water or magnetic rock.  I ran a survey in the Yukon in September on a larger placer property, results were amazing.

What I produce is a topo map of your bedrock.  I also produce a map of surface to bedrock depth.  With this data, you can see your hidden channels clear as day.  As well as deep spots and traps in your bedrock.

Here's a bit of info on my system:  https://www.westcoastplacer.com/bedrock-profiling/

I'm going to be working with some big names in the Yukon in the spring.  As well as some other larger placer miners in BC. 

Unless you have the skills and training to conduct and interpret geophysical surveys then you can't really do this yourself.  The equipment costs a LOT (my system is about $50,000 for the sensors alone).  I offer excellent rates for my services though which are lower than having a resistivity survey done since I don't need a crew or cut lines.



Offline Xplore

  • Full Member
  • ****
  • Posts: 228
  • Province/State: BC
  • Country: ca
  • Kudos: 18
Re: Testing
« Reply #5 on: January 14, 2020, 12:54:16 PM »
Mulletator - magnetic surveys can provide additional insights as well (I'm sure you knew this already). As  a geology field assistant during my student days I was part of a team doing magnetic surveys in northern BC and Nevada as well as resistivity, soil sampling, and stream sediment sampling - all for hard rock / mineral claims owned by junior exploration companies.

North Vancouver, BC

Offline mulletator

  • PPT Invited
  • *****
  • Posts: 45
  • Country: 00
  • Kudos: 7
Re: Testing
« Reply #6 on: January 14, 2020, 03:43:13 PM »
Hi Xplore, I also worked for over a decade in hardrock exploration in the Canadian arctic and all over Canada and the US.  I got involved in placer in the Klondike in 2009 sort of by accident and got hooked.

The techniques that you mentioned serve a different purpose in hardrock than they do in placer.  Resistivity is used to characterize geology in hardrock, usually mapping conductors.  Often along with IP.  In the placer world, resistivity is used as a rough estimate of bedrock depth.

Magnetometers are commonly used to help visualize lithology and in many cases to highlight magnetic high or low anomalies.  I've done a lot of mag myself.

Geochem sampling (soil and stream) would make some sense in placer but would be prohibitively expensive and ultimately not as good as actual gravel testing.

Placer miners usually don't care what kind of bedrock lies under their claims.  It's nice to know, and sometimes there's a local source but knowing whether you have granite or schist or something else underneath your gravels isn't all that important. 

What is important is knowing where your channels and deep spots in bedrock are.  As well as being able to identify bedrock features that can act as traps for gold.

I'm working with some guys this spring that are testing out mag for a placer mine in the Klondike.  The idea there is that, if done correctly, you can map the black sand/magnetite deposits, kind of like a larger area metal detector.   Under the right circumstances that can work.  If we can fine tune the mag and get reliable results it might be a good tool in the future. 

I'm also experimenting with a new technique using drones and multispectral imaging.  That is a tool that's used to highlight different types of vegetation.  The idea is that certain types of vegetation like to grow where there is disturbed/porous ground.  That can correlate strongly to areas where there are underground channels.

It's an experimental technique for now but if successful I'll be able to cover large areas with a long range drone and estimate where hidden channels are located.

The seismic system that I'm working with is the best when it comes to bedrock profiling.  I tested it last year and am going full bore in the coming season.  In a few years passive seismic will be standard on most large scale placer operations.  There will always be holdouts who don't understand technology.

Some guys just like to poke around with their excavator and hope they get lucky.  Even a broken clock is right twice a day. 

Technology is advancing and we're lucky to live in a time when the costs are becoming attractive to placer miners.

Offline Xplore

  • Full Member
  • ****
  • Posts: 228
  • Province/State: BC
  • Country: ca
  • Kudos: 18
Re: Testing
« Reply #7 on: January 14, 2020, 04:46:07 PM »
Mulletator - thanks for the additional context - lots of interesting stuff you bring up!

I personally don't have any experience when it comes to testing technologies for placer other than a good old gold pan and shovel., but it sounds like the technology is there to avoid using excavator time for early testing.

-Xplore
North Vancouver, BC

Offline suburbanator

  • Adventurer
  • Sr. Member
  • *****
  • Posts: 306
  • Province/State: BC
  • Country: ca
  • Kudos: 21
  • https://youtu.be/RhFRkgpURW0
    • youtube channel
Re: Testing
« Reply #8 on: January 14, 2020, 05:25:55 PM »
I am testing the bottom of a beer can as we speak..  waiting for this winter to pass...

Offline Youngnugget(Goo)

  • Full Member
  • ****
  • Posts: 80
  • Province/State: Abbotsford/BC
  • Country: ca
  • Kudos: 2
  • If ya can still feel your hands, your ok
Re: Testing
« Reply #9 on: January 14, 2020, 06:01:56 PM »
Seems like a very interesting but useful technology

 


Gear Pan
Gold Rat