Creeks after floods

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Hi, some of my favourite spots have had huge amounts of water through in the Vic floods - some say the most in 30-40 years. I went for a look yesterday and trees have been uprooted by the water etc, so it’s significant.
I haven’t been prospecting long enough to know what to expect after a flood event like this - wonder if anyone who’s been doing this for a while can let me know what I can expect in terms of my spots being replenished
 
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Hi, some of my favourite spots have had huge amounts of water through in the Vic floods - some say the most in 30-40 years. I went for a look yesterday and trees have been uprooted by the water etc, so it’s significant.
I haven’t been prospecting long enough to know what to expect after a flood event like this - wonder if anyone who’s been doing this for a while can let me know what I can expect in terms of my spots being replenished
Whilst a large scale flood will introduce some new gold to the system it can also hide it very well with layers of wash. Its likely to have opened up bedrock in some spots and covered it in others .
You Just need to start test panning and exploring when it settles down to find the areas it may have concentrated .
 

trekkie

steve
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Hi everyone, can anyone from maryborough area tell me what condition graves track is in and whether its accessable or has storms put it out of action
 
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Whilst a large scale flood will introduce some new gold to the system it can also hide it very well with layers of wash. Its likely to have opened up bedrock in some spots and covered it in others .
You Just need to start test panning and exploring when it settles down to find the areas it may have concentrated .

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So the velocity of water on the bedrock of the stream might only be 25-40% of the river velocity at surface. In many cases that will not re-distribute much gold in the deeper channel. In practice, the gold after a flood is often deposited on its banks and flood plain and is extremely fine grained, because it was being carried in suspension in high velocity water near surface. When the water level drops it is left behind on the banks and the base of spurs. Howitt noted how Chinese miners did well for years washing this fine gold after floods along the Mitchell River, despite there being little or no payable gold in the river gravels within the stream..
 
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Hi everyone, can anyone from maryborough area tell me what condition graves track is in and whether its accessable or has storms put it out of action
@trekkie hey mate. A bit late but I was up that way today.
I didn't go on Graves track but Wells and Centenary are fine so I reckon Graves would be fine as well seeing as it's one of the main ones.
 

WalnLiz

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View attachment 5537

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So the velocity of water on the bedrock of the stream might only be 25-40% of the river velocity at surface. In many cases that will not re-distribute much gold in the deeper channel. In practice, the gold after a flood is often deposited on its banks and flood plain and is extremely fine grained, because it was being carried in suspension in high velocity water near surface. When the water level drops it is left behind on the banks and the base of spurs. Howitt noted how Chinese miners did well for years washing this fine gold after floods along the Mitchell River, despite there being little or no payable gold in the river gravels within the stream..
Very True goldie, and unless the flood was significant enough to expose new bedrock sections previously under a lot of overburden then the mid stream sections are rarely replenished. When however the floods are significant enough to rip out surrounding banks and wash away a foot or two of topsoil from higher banks then the detector operators should rush to check out those new sections of surface erosion. I was lucky enough to be the first after a significant flood on Tuena Creek and was rewarded with half a dozen good nuggets from one bank, the biggest going just over an ounce. I had got nuggets from this same section many years ago and knew many more were still buried under a metre of overburden which would have been not looked upon kindly to have removed with a pick and shovel. When mother nature does it for you then the erosion was from an act of god and that is all OK.
 

Hawkear

Geoff Mostyn
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Yes, movement of something as heavy as gold (sg 19.3) by water (sg 1) is physically very difficult unless aided by gravity.
Read that in the old days when water was very scarce in the Victorian goldfield during summer, the diggers used to pile their washdirt into a seasonal creek. After a storm they would find the heap washed down and the gold just sitting in place.
Have also seen reliable reports during the 80s of bank wash downs in Stringers Creek, Walhalla revealing excellent gold deposits.
 
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Yes, movement of something as heavy as gold (sg 19.3) by water (sg 1) is physically very difficult unless aided by gravity.
Read that in the old days when water was very scarce in the Victorian goldfield during summer, the diggers used to pile their washdirt into a seasonal creek. After a storm they would find the heap washed down and the gold just sitting in place.
Have also seen reliable reports during the 80s of bank wash downs in Stringers Creek, Walhalla revealing excellent gold deposits.
Had good results after heavy flow in Stringers Creek in the early 1960s (using a cradle).
 
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Very True goldie, and unless the flood was significant enough to expose new bedrock sections previously under a lot of overburden then the mid stream sections are rarely replenished. When however the floods are significant enough to rip out surrounding banks and wash away a foot or two of topsoil from higher banks then the detector operators should rush to check out those new sections of surface erosion. I was lucky enough to be the first after a significant flood on Tuena Creek and was rewarded with half a dozen good nuggets from one bank, the biggest going just over an ounce. I had got nuggets from this same section many years ago and knew many more were still buried under a metre of overburden which would have been not looked upon kindly to have removed with a pick and shovel. When mother nature does it for you then the erosion was from an act of god and that is all OK.
Yes - the point being that introduction of new heavy gold to an area in a flood is rare but the flood can remove unprospective material and expose previously inaccessible material from beneath it that has heavy gold.
 

trekkie

steve
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@trekkie hey mate. A bit late but I was up that way today.
I didn't go on Graves track but Wells and Centenary are fine so I reckon Graves would be fine as well seeing as it's one of the main ones.
thanks mate I was there last sat and road was pretty good except for swarms of mozzies it was a good day
 

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