How to read or interpret Geo maps

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Gday all, i have a very basic knowledge of how to read GEO maps, but if anyone would like to share any of their knowledge, it would be greatly appreciated, or even if they can point me in the direction of how to learn, I would like that very much, thanks in advance.
 
Hi - fiststly do you mean geological maps in general or is GEO the name of a software package or file type?

If the former I usually try to assist but that is a bit too broad. The problem being that it is a map depiction of scientific data, and unless one has some understanding of the science it would require too much explanation. The best thing is to ask a specific question about something you are interested in that appears on a map. or show a small map of an area that you are interested in and ask what it is saying about the geology. With hundreds of rock types, thousands of minerals and the 3D issues of geological structure it is just too big a field otherwise. Too many combinations and permutations can occur on geological maps in general to discuss them all, but only a few appear on any limited area on a specific map.

If the latter I am probably stating the obvious - teaching grandma to suck eggs.
 
Hi - fiststly do you mean geological maps in general or is GEO the name of a software package or file type?

If the former I usually try to assist but that is a bit too broad. The problem being that it is a map depiction of scientific data, and unless one has some understanding of the science it would require too much explanation. The best thing is to ask a specific question about something you are interested in that appears on a map. or show a small map of an area that you are interested in and ask what it is saying about the geology. With hundreds of rock types, thousands of minerals and the 3D issues of geological structure it is just too big a field otherwise. Too many combinations and permutations can occur on geological maps in general to discuss them all, but only a few appear on any limited area on a specific map.

If the latter I am probably stating the obvious - teaching grandma to suck eggs.

Thanks Goldierocks, yes I meant geological maps, thanks.
Even a basic understanding would be of some help.
For example, I go to TRILOBITE app, and click on detailed Geology, and i have occurrence layer on, I notice that the colour where gold has been found is in the "Brown" Paleoproterizoic ground, and to the west the colour is different, and there are no occurrences, despite it being very close. the lighter coloured ground is cenozoic materials.
Now my basic understanding of cenozoic, (from wikipedia) is that is fairly young? 2 - 66 millon years, and host to modern plants and animals.
So i am thinking that the age has a lot to do with gold being trapped in the host material, and the older ground has released some of the gold as it decays over longer times?
Should I be concentrating on ground from certain periods of time, that also have certain formations?

Am I anywhere near it? LOL

P.S. i am actually looking for unworked ground where I can, if that makes any difference.
 
Hi Dave.
I presume your question is how to read a geo map to select a potential gold prospecting site preferably unknown by others. The question we all share.
Here in Vic we are lucky to have many Geo maps often usefully at small scale produced by our Geological survey going back many years of work.
Many of these maps show gold occurrences.
I usually try to correlate these with the rock types in which they occur. There are other structures to look for such as contact lines between different rock divisions, reef lines, fault lines etc.
If the gold occurrences can be correlated with any of these things then look on the map for similar structures or combination of structures where no gold occurrences are shown and maybe check those areas out.
Even topographic features can be worth considering such as when a valley cuts through a rock type or contact line known to be associated with gold in other parts.
The older maps here in Vic are very user friendly but I am not sure about the high tech geo maps in other parts of Oz.
Good luck.
 
Thanks Goldierocks, yes I meant geological maps, thanks.
Even a basic understanding would be of some help.
For example, I go to TRILOBITE app, and click on detailed Geology, and i have occurrence layer on, I notice that the colour where gold has been found is in the "Brown" Paleoproterizoic ground, and to the west the colour is different, and there are no occurrences, despite it being very close. the lighter coloured ground is cenozoic materials.
Now my basic understanding of cenozoic, (from wikipedia) is that is fairly young? 2 - 66 millon years, and host to modern plants and animals.
So i am thinking that the age has a lot to do with gold being trapped in the host material, and the older ground has released some of the gold as it decays over longer times?
Should I be concentrating on ground from certain periods of time, that also have certain formations?

Am I anywhere near it? LOL

P.S. i am actually looking for unworked ground where I can, if that makes any difference.
That is the point I am making - the problem being that it varies with where you are, although mostly in a broad sense. For example in the Archean rocks of Western Australia you would be looking at either primary gold in greenstone or alluvial gold in Cenozoic and younger gravels etc. Around Pine Creek in Neoproterozoic to Palaeozoic sedimentary rocks (from memory) and Cenozoic gravels. Around Tennant Creek in Palaeoproterozoic sedimentary rocks especially near ironstone. At White Range in Devonian and younger rocks of variopus types, not older. Best thing is ask about a specific area where you are focussed (not necessarily on-line here).

Gold is introduced into rocks in various specific events, often of fairly limited length (what is a 100 million years between frikends?) You won't find primary gold in the Cenozoic anywhere in Australia except in alluvial gravels or old laterites (the latter being supergene and related to weathering, but not alluvial). But there are few other generalizations - you can see it being deposited from hot springs in the North Island of NZ. So you need local geological knowledge. You obviously have some general idea.
 

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