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This thread is for all of the different rock types in Alaska.

 

Show us your rocks!

 

This summer I will be sampling geophysical anomalies in Alaska. I will publish in situ and first ever published photos of the mineralization here.

 

- Geowizard

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Well, some rocks have conductive mineralization. Some rocks are magnetic. Mankind has produced a few electronic types that also are interested in rocks. They developed metal detectors that can be carried on Helicopters. So they do airborne surveys and locate mineral deposits that contain conductive and magnetic rocks! 

 

The geophysical contour maps are like a topographic map but different. These contour maps show where the high and low conductive mineralization is and high or low magnetic intensity in the rocks. Interpretation of the contour maps can increase the probability of finding a precious metal deposit.

 

So, with the locations plotted on a topo map, it's just a matter of going out to each of the anomalies and sampling the rocks to see what the metals are in them.

 

- Geowizard

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Well, some rocks have conductive mineralization. Some rocks are magnetic. Mankind has produced a few electronic types that also are interested in rocks. They developed metal detectors that can be carried on Helicopters. So they do airborne surveys and locate mineral deposits that contain conductive and magnetic rocks! 

 

The geophysical contour maps are like a topographic map but different. These contour maps show where the high and low conductive mineralization is and high or low magnetic intensity in the rocks. Interpretation of the contour maps can increase the probability of finding a precious metal deposit.

 

So, with the locations plotted on a topo map, it's just a matter of going out to each of the anomalies and sampling the rocks to see what the metals are in them.

 

- Geowizard

So, with higher numbers signifying a high magnetic anomalie and degrading with the lower the number... 0 being No anomalies? Then I would want to check area with higher numbers for material.. if this is what im understanding !

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Dick,

 

That was my thought. But I didn't go there!

 

However, yes, recognition of rock types and associating certain rocks that might identify a certain gold system per the reference given by Chris in another thread could be helpful in prospecting.

 

With reference to geophysics; rocks have physical properties that are unique to gold mineralization as well as other precious metals and base metals. The internet has lots of information on the relevance of resistivity and magnetic properties of rocks and the importance of those properties in prospecting.

 

Rocks that are magnetic contain magnetite. Magnetite is know in some ares to be associated with gold. Find magnetite - Find Gold. :)

 

Rocks that conduct electricity have mineralization that is conductive. The more conductive the rock is, the more conductive mineralization! So, resistance and resistivity are inversely proportional to conductivity. That means when resistivity goes up, conductivity goes down. When resistivity goes down, conductivity goes up.

 

- Geowizard

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Dick,

 

I spent a couple of weeks looking over the geophysical survey of the Fortymile. I also looked carefully at your creek and surrounding area.

 

I have compiled about 144 mineral deposits that are presently unclaimed. Millrock Alaska and AERI as you know are big players in the Fortymile.

 

So, I'm also offering to do a selective evaluation of anyone elses claims in the Fortymile. The importance of the geophysical interpretation is that is defines hardrock deposits that are probable sources of placer gold. I found placer deposits that have a definite geophysical signature that have never been claimed.

 

- Geowizard

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Placer deposits have magnetic signatures, but I will bet there are no two alike. I would like to compare two known placers that have not been mined. They are around. In fact you and I know at least two of them.


Show us your maps, Geowizard.

Geo Jim

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