Geological Maps - information and questions

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Thanks Loamer, look forward to expanding my research, this paper looks absolutley fantastic!! will be printing it off and devouring it!
 
Hello all, I am in need of some info and from what I have read on the forum the is the place to find the answers.
I have been interested in Fossicing and prospecting for many years and now that the company that I work for is going under and kicking us all to the curb it is perfect time to go on a golden holiday.
Now, having spent the last 5 weeks of work doing research on the subject I have found the geological maps of the area that I plan to detect, sent an email to DMITRE to find out about the current Tenements and called the local station managers for permission and all good on that front............

Then I started to hone in on just exactly where I should start..... Well it gets a little tricky for me here. The area is HUGE! like 620 odd square Kms :|
So in comes the geological maps, I look in the area and see that the gold fields are in the same type of ground on the map and notice that this ground occurs in an area about 20kms away but no Old timers mines are in the area?
Could there be virgin ground?
Should I just stick to the old timers diggings?
I was thinking of going into the areas with the same ground but no mines and taking a few sample pans in the creek beds (no water ANYWHERE).
Now I have not physically walked the areas in question I'll have plenty of time to do that soon enough, this is my research time.

I got the maps from the Geo-science Australia website.

SApicker

P.s. I am new to this, so new in fact I can still see my face in my skid plate. This forum is fantastic thank you all for your shared wisdom.
 
Hey, I'm with you so will be interested to see what other response you get. There is quite a lot of knowledge on this forum from people who have been doing this for quite some time.

I've been on so many websites (each State) and have downloaded quite a list of maps and writings for each State and have been methodically going through it all. I guess we all would LOVE to find that virgin ground. Nothing to say we can't....comes back to research and it sounds like you are on the right track.

From what people have told me and what I have read, it is pretty much a given to understand at least the basics about minerals associated with gold bearing areas to give yourself a fighting chance.

I downloaded a huge minerals reference from WA Minerals & Petroleum website called Minerals of Australia. About 400 pages and it covers the lot (gold, minerals, precious gems & occurrences Australia wide) including great maps etc.

Doug Stone's Metal Detecting for Gold in Australia also has excellent information, great tips and many, many maps. Have read old readings by Johnson, Erskine and other great links I found on this forum. Truly inspiring! I've joined the online library and now have access to loads of other reading materials old and new for free (Trove).

For myself, I will start in known areas and perhaps wander further afield once I gain a bit more experience and knowledge. Happy Prospecting! Let us know how you get on and what you decide to do.
 
That's a very interesting question. Having no idea what state you are in I would just like to say that if you can some idea as to what geological era your primary gold was found in, then that could correlate to the map. (is it lower palaeozoic for example) Also, which way do your reefs systems run? What were the indicators of gold? Are there dykes (and what type of dyke), faults, reefs, granite inclusions etc. Correlate the maps with any Deep Lead maps you may have as well (Deep Leads will be too deep to detect usually). Look for gullies in your virgin area with the same geological attributes. Just because the maps are not marked as 'gold workings' etc, I can tell you that walking these unmarked grounds will surprise you and that there may in fact be some diggings or test areas. Remember - the old blokes had to try and get an ounce a week to survive - what was a shizer for them can be 'gold' for us.
 
Thank you for the replies guys.
Loamer I am mainly looking in South Australia at the moment, around the Olary area. I have had a look at the era and it is late Proterozoic, Adelaidean, Marinonan with a mix of Farina subgroup and yeralina sub group (please don't ask me what they all mean).
As for the reef's I'm not sure but I think they call them Bed's on the map and the run east west and they do the same in the area that I am looking in.

What I have been doing is I will bring up the Geo map zoomed in to the area I am looking at and then bring up Google earth to the same area.
I then go back to the Geo map and find two or three good and easy to see reference points and with a white board marker I mark the screen.
I then go back to Google earth and pin point the reference points with stick pins on the program then with a bit of stuffing around with zooms on both I line them up.
It does take a bit of stuffing around but you can get it quite accurate, once done I break out the trusty white board marker again and bring up the Geo map.
Finding as many Diggings, prospects, mines that I have read about and ground that I think looks the same and mark them on the screen.
Then I go back to Google earth and put pins in all the spots using different colored pins for each type.
Now the fun part starts, I then start with all of the old mine pins and see if I can find them (original pins are not absolute) when and if I do find then I zoom right in and change the pin location.
I have tried this with a test run at work (in the bush) and I compared the GPS to Google earth (pin) and it was only about 10m out on a Garmin etrex 10.

I don't know if anyone does this but I thought I would post it.
Cheers SApicker
 
In the 1908 Mines of SA Book - Olary - the rock formation is gneissic micaceous granite, mica slate etc with eruptive granite. (Granite inclusion I suppose) it also says there are numerous quartzose and ferruginous reefs which appear likely to contain gold. In 1889 it was reported that a strong lode could be traced fully 2 miles bearing E.N.E. If you have the book - page 185. It is one of the best books I have ever seen.

PS. Excellent posts, questions and follow-up by the way!
 
Hey, I just had a look at this - you can view it free of charge on the online library Trove and it is searched as follows:

Record of the mines of South Australia. by South Australia. Dept. of Mines. 1908

When I checked it out it shows 'Olary' so I'm thinking it's the book loamer mentions?

Record of the mines of South Australia.
4th ed.
Compiled under the authority of the Hon. Laurence O'Loughlin, by Lionel C. E. Gee. H. Y.L. Brown, Government Geologist.

Published 1908 by C. E. Bristow, Government Printer in Adelaide .
Written in English.

You can save it too but I didn't tell you that.
 
loamer said:
In the 1908 Mines of SA Book - Olary - the rock formation is gneissic micaceous granite, mica slate etc with eruptive granite. (Granite inclusion I suppose) it also says there are numerous quartzose and ferruginous reefs which appear likely to contain gold. In 1889 it was reported that a strong lode could be traced fully 2 miles bearing E.N.E. If you have the book - page 185. It is one of the best books I have ever seen.

PS. Excellent posts, questions and follow-up by the way!

Hi loamer

close

gneissc( pronounced like the biscuit, nice) and granite are the same in essence, and bloody hard, gneiss's mobs scale varies on the sample, yet to see one under 7, and mostly in the 8, 9's.

gneissic micaceous granite, means looks like mica, will have a slate type appearance, with a low hardness. Mica can rate from 1.0 to 6.0 on moths, and for a comparison you may recognise, quartz is 7.0, so this formation could be as soft as talc, or almost as hard as quartz.

mica slate, again this is pretty wide by todays standard, by given that the area was subjected to high heat during it's history, I would expect that you will find poorly formed slate.

eruptive granite, oh this means stay away, essential it means the sedimentary rock in the are was subject to intense heat and pressure. I don't have the surface geo map for the area but I bet there are a few faults, and if you could lay you hand on a geo map with strike and dip, it would be littered with them. Basically this gear, needs to be drilled and blasted, it's hardness and resistance factors are so high, the hydraulic hammers on excavators, they just melt their moils trying to break it.

ferruginous reefs, containing iron oxide, so normally they would list the main component of the reef but if the description is right, then you would be looking for red calcium, or iron ore thats been subject to intense heat and pressure, sounds weird personally, and wouldn't be the first time an surface geo map had a bad description. Hope you have a high end detector, sounds like the mineralisation will play hell in that area.

Go prepared, Good luck
 
That's the one!! Cracker of a book isn't it! I had to go to about 200 different original sources to get anything close to create my own for Victoria. There is also the handbook for prospecting in SA - Dept of Mines - 1952. I have a hard copy and don't know if its available on-line.
 
So much information!!! Glad I don't watch TV ;)
Cheers for the site for that book penfooey
 
Hi SApicker, sorry to hear you lost your job, hope is at hand..

A couple of points first up, 1. Try to get the 1:100k geo maps of the area of interest. 2. Take a bit of time to look at the marginal info on the map, this will tell you the age and color of the rock, this comes into play later. The "sub groups" you mention in your second post refere to geological formations, my understanding is they are usually named after the largest piece of same type of bedrock in the region, this region can be quite large, (100s of square km's)

When I look at a Geo Map, I look for the areas that are in the Quaternary period, these are the alluvial soils that carry the alluvial gold. They are usually marked as Qa or Qd or a capital Q and some small letters, the small letters tell you the type of parent rock. the marginal info will give you a description so you know what to look for in the field This is the stuff that surface prospectors are looking for.

What Loamer and Village have said are a good guide, a bit complex in technical info and may have overloaded you. I look at the areas of alluvial deposits and then have a look along the boundaries of of these areas, usually this is where the the bedrock is mos worn smooth, but there are also crevices there. You need to read the land also and there are a few good threads on that topic.

I try to follow three steps.
1. Find the area on the geo map, then do some research to see if any gold was found in the area, old mines department reports etc. The maps are usually marked with a red pick and shovel...
2. Locate the spot on the ground or use a Topo map or google earth to see the what way the ground lays in relation to the Geo, the ones I get from Qld Mines dont have contours so you cant tell by looking.
3. Look along any water courses for flat areas where the ancient water may have flowed, pay attention to any bedrock that protrudes and then sample around these, the harder rock will have created low pressure areas when the water was flowing and hopefully deposited gold..

I apply these principles when I go out and they seem to work for me. I don't get out much but I have never returned empty handed.

work on your panning technique at home, I don't know how experienced you are at panning, if you are new, get a pan you can afford, put some gravel from the garden in to the pan and chuck in a few small pieces of lead, split sinkers work well, or shave a few bits of a large sinker, chuck them in and go for it.. you should be recovering all the lead sinkers after an hour or so of practice. check Youtube for how to pan for gold videos

If you go the detector route, I am sure the lads and ladettes on the forum will give you the good oil.

Cheers, Tone
 
Thank you Tone. I will be putting this in full effect in April when we all get the boot. Perfect timing I think, the weather will be fantastic in the desert that time of year. It also gives me another three months to study. 8)
I am so glad that I stumbled across this forum, Decades of experience and friendly like minded people willing to share that experience.
 
I am still new to gold detecting. (have only found one nugget so far). I have just started looking at Geoview and Geology maps. What should I be looking for on these maps that may help me find locations that are likely to produce nuggets. Any help would be appreciated.
 
Does anyone know where I can buy hard copy 1:250,000 scale geological maps. You used to be able to buy them from the Geological Survey (Geoscience Australia) in Canberra, but they don't sell anything anymore and they do not know where to get them from either.

Araluen
 

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