Deeper ground and what to look for???

Hi All,

I have a couple of frustrating questions I would like answered if possible?

I was out yesterday in a new area which has quite steep hills and gully's and plenty of signs of past old timers.

The mine holes were about 15-35m away from the current gully's, so I assume that the old river / gully bed has moved over time. The mine depths were from approx 5m - 15m from what I could see. There was not allot of signs of exposed reef or river gravels in the throw outs, but lots of pipe clay's and iron stone slates.
My first question to anyone is am I wasting my time in this type of area or how would you go about detecting it??

My Second Question

Later in the afternoon we went to a surfaced area in Doug Stones book near Avoca. The area is quite extensive, but unlike any surfaced areas I have worked before. There was no signs of bed rock or shale rock like I experience in the Castlemaine area. I dug a few test holes and could not find the bed rock.

The question that I have is what did the old timers use as a base line when surfacing this type of area ( how far did they go down and to what level??)

look forward to any help

Mariner3800
Pete

Hi
Ive always looked at the trees as an indicator of deep ground the biggest trees will be growing in the deepest ground /old gutters etc and the growth gets smaller as the ground gets shallower to stunted runty growth where there is hardly any topsoil on bedrock .

I dont detect deep ground like you describe because to me the gold is either at the bottom of those holes or in the mullock at the top .

Hi Pete,
question 2 - from my experience the 'base line' that the gold diggers ages ago aimed at was a clay base.
They dug up all (or most of) the gravels and 'hill wash' that sat on and above this base of clay.
This is where they discovered the gold had concentrated in. The depth of this 'wash' varied and was (is) usually patchy. They also discovered like most clay with weathering over time that the clay expanded and contracted with the seasons thus forming cracks which 'collected' gold particles. So they removed some of the clay to process as well.

I have detected small gold nuggets from ground like this from within this clay. (possibly gold that has been caught in a crack).
In some areas you can still see trees growing with their root system beginning above the existing surface level thus giving a bit of an idea how much 'wash' was dug and removed from the surrounding area.

regards Cb.
Scott

Clay Base wrote:Hi Pete,
question 2 - from my experience the 'base line' that the gold diggers ages ago aimed at was a clay base.
They dug up all (or most of) the gravels and 'hill wash' that sat on and above this base of clay.
This is where they discovered the gold had concentrated in. The depth of this 'wash' varied and was (is) usually patchy. They also discovered like most clay with weathering over time that the clay expanded and contracted with the seasons thus forming cracks which 'collected' gold particles. So they removed some of the clay to process as well.

I have detected small gold nuggets from ground like this from within this clay. (possibly gold that has been caught in a crack).
In some areas you can still see trees growing with their root system beginning above the existing surface level thus giving a bit of an idea how much 'wash' was dug and removed from the surrounding area.

regards Cb.
Scott

Also to add further, the clay base that is exposed thanks to all that hard work the 'old boys' put in is now oxidised thanks to a hundred plus years of exposure to the elements, chances are it would have looked a lot different when they were first removing the wash layer all that time ago. I have dug multi ounce nuggets in clay base surfaced areas a number of times over the years so it pays to not judge what you are looking at as being true bottom, as the previous poster said sometimes cracks open up in the clay and nuggets and wash will accumulate in them and was often be missed by the old boys who were going by feel with their picks listening for that crunchy sound of the pick on quartz as their guide whilst digging. The clay would have once been bedrock but is now commonly referred to as deco (decomposed bedrock), in granite country the deco can go down for many hundreds of feet until true unweathered granite is struck, same with the schist country. Clays are your friend with a PI unit as some very nice gold can hide within and can be easily missed.

JP

Thanks bruiser, Scott and JP,

Thanks for the info, it is now becoming a little clearer

Peter
Mariner3800

mariner3800 wrote:

The mine holes were about 15-35m away from the current gully's, so I assume that the old river / gully bed has moved over time. The mine depths were from approx 5m - 15m from what I could see. There was not allot of signs of exposed reef or river gravels in the throw outs, but lots of pipe clay's and iron stone slates.

Mariner3800
Pete

Depends how keen you are mate and how rich the area once was. I know a bloke who used to put an extension ladder down these holes and dig out virgin wash,bucket it to the surface via his winch on the 4wd,spread and detect it.
The biggest nugget he got was a 16 grammer.
The danger is cave-ins and earth falls or whether the old timers got all the good wash to begin with.

Hi Peter
There are somes areas that get you scratching your head.Theres one huge area in Avoca that weve never got a piece from.I suspect that the surfacing done there is not for gold but removal of the gravels for building.Also an area in Wareek.Looks beautiful but its odd,go to the mullocks and theres not one dig hole on them.The only conclusion I can come to is that undetectable fine gold has been recovered.
The trees are still your best friend in the triangle.By looking at that ring of gravels around the base of them (that has been brought to the surface by growth)you know exactly whats under your feet (especially look for where the gravels change from one colour to another).When the gravels disappear its generally too deep for detecting .The height of the mullocks is a good indicator of depth.A good rule of thumb is if you want to detect to the bottom with a medium to large coil if the height of the mullock is over 12 to 15 inches the ground is too deep.This takes into account over 100 plus years of erosion.
Kath and I chase gold between the surfacing and the source or on the slopes leading to gullys.Kangaroo Gully at Talbot is a good example,way too deep for detecting but gold has bled off the surrounding ridges into the gully(theres a lifetime of detecting seaching those slopes alone)Occasionaly we get lucky on the reverse side of the ridges.In general the slopes are less 10 degrees or less (the gentler the slope the more time it takes for the gold to reach deep ground)and the depth to the bottom is less than a foot.
Happy Hunting
Cheers Noel

Hi Noel,

Thanks for the great info, I hope others get to read your comments as it is great info and I'm in your debt for sharing it in such an easy to understand way, unlike allot of books I have read.

Thanks again

Peter

Hi mariner3800
I have dug down 3 layers so far in the mine shaft I am digging at the moment.
I will be digging to the bed rock or clay base.
The story is in the attachment below.
Regards Neale



https://golddetecting.forumotion.net/t7514-new-project-for-next-year-searching-for-ancient-watercourse-like-the-diggers-of-old

Hi Neale,

What a fascinating and exciting project you are undertaking. As one post recommended, are you doing any video on it as it would make great viewing?

Really look forward to the next chapters of you venture

Thanks for the link and post

Peter

Hi
Yes I will Video This as I go.
I am going out Friday for a few more days.
I am very excited with what I have found so far.
The trees are older like I read in your posts so that makes me more positive about the spot I am digging now.
I saw the TV show last night on SBS 2 and the ground looked the same, it was a great show.
I am glad my link has related to you topic.
Regards Neale