Gold, Faults and Fluids
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- เผยแพร่เมื่อ 26 ส.ค. 2024
- International expert Professor Rick Sibson talks about how fluids, faults and earthquakes interact in the crust to form fault-hosted gold deposits. Ken Harris has mined a typical fault-hosted deposit at the Red Robin mine in the Alps of southeast Australia. See more films about gold at goo.gl/0mw8Z4
Wow! That's my great uncles mine. Bill Spargo (The Hotham Hermit) lived up there for 27 years. He had a hunch that the Ballarat goldfields ran through the high country. Whilst prospecting he spotted a Red Robin sitting on some quartz which became the Red Robin mine.
My Father who did security for the S.E.C took me their a few times !
Great work Clive. Thanks for putting these videos together.
Incredible knowledge
Thanks for sharing
Hopefully I can find more gold on the surface now. I've allways loved rocks I actually found a water warn quartz boulder that contains volcanic opal behind Coffs Harbour in the old gold feild. it was my boulder opal mining day's that made it catch my attention and on closer inspection with my Geo hammer that confirmed my suspicions visible clearly under my loop. I showed and gave Mac at Bellingen opal shop a few of the peices he laughed and said they may contain gold but definitely not Opal when he saw it his words were this belongs in the Australian museum. I still have the king stone I never showed him.
Cheers Bruce
Fascinating series; you are re-enthusing this amateur geologist! Thanks
Thank you very much
These are great videos. thanks for going to the trouble to product these.
I'm a caver in Jamaica, and after watching this I realize that a lot of our strike passage caves have a dip at about 30 degrees from horizontal. Very glad I watched this. Many thanks.
Thank you for watching
I know it's an old vid but I like to add that I'm on the earthquake ride, but I lean much more toward the bridging effect of the crust over a pluton taking away the weight of the rock above and leaving much less weight over the pressurized pluton and that makes it easy for the fluids to push up, crack and fill the fishers. Lateral pressures can ease up and the bridging loses it's effect returning the weight. Several episodes will leave the same streaked veins. An earthquake would be a side effect not a cause.
Very informative and well produced. Enjoyed this video immensely.
Thank you for perfect done videos,excellent done!!!!❤ Fredrik From Sweden!
Thank you very much for watching.
I enjoyed this video very much with my morning coffee , now I will have to subscribe and watch more of the series
I am a prospector in the American west
I had a step dad (when I was a teenager) who grew up in Kellogg Idaho ( Glen Smart ) and worked underground all his life in mines around the world . He had very little formal education . He taught me quite enough to make a prospector out of me for life . I will soon be 64 . that seed made an amateur geologist out of me
Calif. to Nev. to the Carolina's to Idaho/Mont. to Wash. to Alaska and now back in Washington ( Eastern )
Working placer deposits for super fine gold. ... But always an eye on the geology everywhere I go . This vid. fanned the embers
Thanks for your comment. When the gold bug gets you it's hard to shake it off, and as you say, it opens your eyes to geology in general. The amazing thing about gold deposits around the world is that they often look the same, basically because the processes that formed them are very similar. All the best for your prospecting.
Yes they are ... same with high bench placers
they are everywhere and the ultra fine gold collects about the same everywhere
Thanks that was like a delicious entree, I’ve subscribed, I’m a mug but travelled all over Oz outback looking and collecting but never understanding. Over in the goldfields of WA we came across an area that had low aligned hills that were either predominantly white quartz or black iron stone, but the weird part was they were adjacent to each other and occurred over a fair area. I’m sure a geologist would know why, thanks
Wondering in karakurams..thanks for the great data.
Great video
Thanks for watching
All geologist can relate to great ideas starting with beers at the pub with fellow geologists!
That is exactly the method used to outline that uranium deposits could exist in N. Saskatchewan...geological discussions over a beverage about the unconformity deposits in Australia.
Fantastic presentation.
Many thanks!
is it common for mineralisation to be in higher concentrations in faults that are at steeper angles to the axis of movement or axis of force ?
if faults at 10 - 20 degrees have lower horizontal kinetics (force) acting on them , is it possible that enriched hydrothermal mineralisation will not occur on these locations due to the low pressure and temperatures generated , while fluids will still flow through them angles of 30 degrees or more will support higher pressure / temperature and be more likely to produce mineralisation ?
Nice .. thanks.. I understand it a bit
Nice job with the stolts!
Raises the question of fracking!
Not really. Fracking is mostly used in oil and gas extraction. I've never heard of it being used for gold mining.
I have watched all seven videos.
Very enlightening.
We have a small gold lease in WA. It was mainly to fossick for a bit of surface gold. Which we have found.
The surface rocks have intrigued me, with fault slicks and gneiss just laying on the surface. There are small hills covered in degrading green schist with veins of quarts just breaking the surface.
To add to this we have found thumb sized quarts/ironstone specimens shot with gold and with like a gold netting pattern on the surface.
Watching these videos has got me thinking that there is a possibility that the origin may well be deep in the hills.
I wonder why no one has done any exploration work before.
Should I take that as there i signs that would say it’s not worth it or is there a newer thinking about metamorphic faults the old timers missed.
Thanks for watching our videos. Based on your description it sounds like the surface gold in your lease is probably derived from the local quartz veins in the schist - my guess is that these are Orogenic style gold-quartz veins. So yes, I think there is potential for exploration beneath the surface.
@@GeologyFilms guys who use detectors to retrieve gold at surface and do no further investigation are doing a great injustice , If they recorded and mapped these locations with ore samples provided for later analysis it could open up huge underground discoveries in future generations that might now be missed completely.
Interesting
Great information and very Interesting stuff to learn, thanks.
Good vid very few are as enteresting
Is this process still taking place today? It is common belief that the gold was laid down during the tertiary period.
When the fluid enters the fractures in the faults after a seismic event is the gold in solution and then some how precipitates out later ? or is the gold actual particles simply just transported by the fluid? And finally has an effort ever been made to locate the fluid and then bring it to the surface to extract the gold by precipitating it out ?
Thanks for the great video. It gives us a chance to see the great minds behind the mining industry success. It has taken centuries if not millineums to aquire the knowlodge these men posses. They are an elite breed of professionals.
Yes this process will be happening somewhere today, most probably near one of Pacific 'ring of fire' belts - especially where rocks are being deeply buried and metamorphosed. Orogenic gold can be any age - in eastern Australia they are mostly between 380 and 440 million years old. In Western Australia they are much older but some of the California deposits are much younger. Yes the gold is in solution and precipitates out later - gold is thought to form soluble chemical 'complexes' with chloride and hydrogen sulphide.
@@GeologyFilms
Thank you for replying to my comment. Living in california ( boo hisss boo ) I have been Searching for gold almost my whole life but yet to get rich. Failure to succeed would actually be closer to the truth . I have panned , dredged, high banked and have some experience messing around in mines. And it is my recommendations not to do the things i done. Mines are no joke and you have no idea that you have no idea how deadly a played out mine can be. And its not just the risk of collapse or drowning the air is bad and you wont even know it untill it is too late. Even though i have yet to find the mother load i have seen the elephant and it is a life long journey that you keep learning from and come out enriched with the rewards of learning so many different things i would encourage everyone to explore the history and science behind gold. It is just such a rewarding way to enjoy life.
How did the old miners know all the stuff about the faults? They didn’t have the technology we have today and not trying to insult them, but I suspect many did not even have a high school equivalent education. It really impresses me what they knew back then, but how they knew it baffles me!
It's a great question. The old miners were pretty clever and they learnt from experience. They observed how veins had formed in lots of different mines and soon realised there were patterns they kept seeing from mine to mine. Also, geologists and mining engineers arrived on the scene about 18 months after gold was discovered in mid 1851. Eventually those geologists/engineers started writing articles in local newspapers and in government reports. By the mid 1860s they understood that gold-bearing veins and faults were related. Over the next 30 years or so, mine managers became more educated through local educational institutions called 'Schools of mines' and they would have instructed the less educated miners. As you say, most ordinary miners would have left school at age 15 but the state of Victoria (in SE Australia) had compulsory education from 1872 and one of the highest literacy rates in the world. And because there were so many scientific articles in local newspapers, the general population probably knew more about gold than people today.
Farron plate and the fault line up pushing under
Excellent content! Thank you.
Thank you very much for watching.
thank you
Watch from 8:19 to 10:33 all you GOLD HOUNDS out there. Its a bit of some jewel of wisdom.
Excellent
Thank you for your comment
C-make more gold vids! HAPPY NEW YEARS! From-25c Idaho. Cheers, jd
Superb! Thanks!
Thanks for you support.
Thank you for this vid!
Thank you for watching
Really good information!
Another great video!
Kinda like the lid bouncing around on top of a pot of boiling water. If you put a brick on the lid, it will stay on and leak out instead.
That's a good analogy
what about those qtz veins that are being squeezed out of the rock itself
Currently my village is under the big vibrations horror sounds of earth quake every one is afraid of constantly earthquake ..it sounds like big blast ..
No body can tell us about the big sounds .can you plz tell us about this big issue in karakurams Gulmit Hunza valley I'm Faryad .thanks
In earthquakes the initial wave to reach you is called the P wave, or Primary wave, which is a compressional wave. The P wave arrives first because they are faster than the later S waves, which are called Secondary waves or Shear waves. P waves are like sound waves so the first thing you experience in an earthquake is a bang, or blast - and that's the P wave arriving. When the S wave arrives, maybe just tens of seconds later, the ground starts to shake.
@@GeologyFilms Thank you Soo much . ❤️ Some geologists came on research here some days ago and. They find the fault near a hot spring they said megma is just 150km depth..here. ..still it sounds .
And plates junction point Hunza was a part of Australia in past .. 😊 may be ..
How about the difference between the volume of feldspar melt and feldspar solid (Larger). As feldspar melt solidifies in an old volcanic system, interior pressures increase and the hydrothermal fluids escape thru a crack when the feldspar solid fractures.
Good question but I don't know the answer.
you are talking about magmatic processes, not hydrothermal processes. These quartz-vein-hosted deposits form by precipitation from hot aqueous fluids, NOT by cooling and crystallisation of a magma.
great vid, thanks
Is there dating on those punctuated pressure events when the water flowed in through the veins?
The radiometric dates done so far in SE Australia just give a general age for a whole vein or deposit with an error of +/- 2 million years, at best. The veins in Ken's mine haven't been dated but they probably formed about 400-420 million years ago. The resolution of the dating systems would make it difficult to date discrete events in a single mine unless they are separated by > 5 or 10 million years.
This is my dream! To own and work my own mine. It's not about the money for me, although that would be a really nice bonus!
For me it's about finding new geology that I have never seen in person before. If I could work a mine and keep the Bill's paid and have a little savings on the side that would be a dream come true! I'm working towards my dream! Hopefully this year I can make that dream a reality!
Yes I agree Geology is a great passion - it's not always about the money from gold.
Sounds like similar physics to sand dune failure. That happens in the low 30s in degrees.
I have seen quartz veins in Arizona that have other veins-fractures that run at 30 to 45 degrees to both sides from the larger vein ..... These could be created by earthquakes ?
Yes they could be the result of earthquakes. It’s very common to see smaller veins formed at an angle to larger veins - sometimes they have a slightly curving shape and have pointy ends. Miners in Australia called them spurs and it’s possible to calculate the direction of stress that created the veins using the angular relationships.
@@GeologyFilms Thanks for the videos, they have helped me understand the mineral geology around the gold fields here in Arizona !
@@GeologyFilms can you recommend a scientific paper about the calculation?
The types of veins commonly seen next to faults are called en-echelon veins or sometimes sigmoidal vein arrays. There are some very good and free online resources that describe how they form, but if you have access to journal papers, or are willing to pay, you could start with this early paper on the subject:
Beach, A, 1975. The geometry of en-echelon vein arrays. Tectonophysics 28, 4 p. 245-263.
Some free online sources are:
structuredatabase.wordpress.com/brittle-shear-sense-indicators/
click on En Echelon Veins
This video has a good description of how these veins grow in shear zones: th-cam.com/video/mM4FlCyX6cs/w-d-xo.html
Haakon Fossen, is a Norwegian structural geologist has some excellent online resources. Check him out at folk.uib.no/nglhe/
His emodules are excellent -
folk.uib.no/nglhe/StructuralGeoBookEmodules.html
Chapter 8 and 15 both briefly describe en-echelon veins and have animations showing how they grow during fault movements.
Has anyone demonstrated water hot enough to dissolve gold?
Yes. Many researchers have. The high solubility of gold in both bi-sulphide and chlorite complexes in hydrothermal fluids as is well demonstrated experimentally, and in nature (including in modern geothermal springs, etc).
How is this safe?
For an experienced miner it is safe. Ken Harris is a very experienced miner who safely operated this mine for over 30 years. But you always have to be alert to the danger and not take shortcuts.
Narrow veins is very dangerous.
Yes these small mines can be dangerous but the owner of this one was very careful and experienced - he used a lot of stulls to keep the walls apart.
Did you find fossils in these quartz next to faults?
There are fossils in the sedimentary rocks that surround the quartz veins. The most common fossils are Graptolites which were planktonic, meaning they floated freely in the upper parts of the ocean. When a graptolite died it sank to the seafloor where it was buried in mud.
Geology Films oh that means that these rocks were soft and the fossils were trapped by flood waters, so the quartz veins didn't have to cut through hard rock rather it was soft material and even with little pressure from bottom they could easily build veins,it's like releasing bubbles inside mud...
nope
Very interesting... #GeoEntire
YeeeeeeeeHaaaaaaaa
Actually working the mine is a nasty job, You've got to have the fever to be motivated enough to do so.
The earths radius has increased over time, opening the earth creating fracture gaps, which filled with quartz
Really just shows geologists have absolutely no idea how it all works lol
None of these geologic theories can be proven in laboratory...show me liquid quartz please...I'd like to see gold trapped in hydrothermal fluid traveling upwards please...
ever heard of primary water there is more water in the stone at depth than in all the oceans on earth on the service that a well known fact
He didn't have to go to Scotland to learn that a fault doesn't creep it jerks loose and one side moves sometimes 30 to 40 feet from the other side. I live in California for 68 years and have worked in Mining for 40 years. I know as much if not more than any Scientist does about faults and Quartz Veins. A fault is just a crack that sand fills and over time turns to quartz Some times Gold and other Minerals are trapped in the Sand / Quartz and solidify as crystals.once Gold comes in contact with base metals in the walls of the Fault Rock or the silica itself.
Faults sometimes do creep, though. Sand doesn't just turn into quartz in a fault. That's not how gold-bearing quartz veins are formed. You need super-heated, super-saturated fluid under pressure.
what role did you have in the mining industry dan?
I think the California fairies wave their magic poles and turn the sand into gold laden quartz. Then the hot fluids are pushed up through the gold veins, and that's how golden showers are formed. At least that' what I heard in some pub down in San Francisco.
...."I know as much if not more than any Scientist does about faults and Quartz Veins."....lol...