Metamorphic Gold

[Deleted]

So, all this discussion about meteor origin of "all new heavy metals" lead me on a wild goose netsurfing session.

It turns out that gold CAN come from deep below and be deposited thru aqueous solution. Similar in process to agate formation. Wow? Who'da think it?

Earthquakes make gold veins in an instant

When mineral-laden water at around 390 °C is subjected to that kind of pressure drop, Weatherley says, the liquid rapidly vaporizes and the minerals in the now-supersaturated water crystallize almost instantly — a process that engineers call flash vaporization or flash deposition. The effect, he says, “is sufficiently large that quartz and any of its associated minerals and metals will fall out of solution”.

The entire article is a killer read for those interested.

1dave
vegasjames
@youper
toiv0

[vegasjames]

Makes some sense. It is well known that the gold is dissolved in supercritical water, which can form the deposits. So once the water is no longer in the suprecritical state it makes sense that the gold would "fall out". The only thing that does not make sense is where they talk about the water instantly vaporizing. Vaporizing to where? The water is within a closed space so unless the water is decomposing in to hydrogen and oxygen, which is highly unlikely, I just don't see it vaporizing as they claim.

[1dave]

Sorry, I don't buy it.

I can see gold, quartz and water coming form the top 100 km, but not through 5,000 km of iron from the core.

[vegasjames]

Jan 16, 2018 21:10:29 GMT -5 1dave said:

Sorry, I don't buy it.

I can see gold, quartz and water coming form the top 100 km, but not through 5,000 km of iron from the core.

They did not say from the core, they said from the crust.  Gold had deposited since the "cooling" of the Earth thus not all gold went to the core. And how much came up in magma?

Here is a dilemma.  Denser compounds will sink below less dense substances. So why did iron and nickel supposedly sink to the core but not the heavier elements like uranium, platinum, etc? Theoretically the gold would have sunk, but floated on top of these and the nickel on top of the gold. So either not everything sunk to the core, stuff was brought back up to the surface from volcanism and other means, deposits formed afterward or all of these

[1dave]

Jan 16, 2018 21:36:18 GMT -5 vegasjames said:

Jan 16, 2018 21:10:29 GMT -5 1dave said:

Sorry, I don't buy it.

I can see gold, quartz and water coming form the top 100 km, but not through 5,000 km of iron from the core.

They did not say from the core, they said from the crust.  Gold had deposited since the "cooling" of the Earth thus not all gold went to the core. And how much came up in magma?

Here is a dilemma.  Denser compounds will sink below less dense substances. So why did iron and nickel supposedly sink to the core but not the heavier elements like uranium, platinum, etc? Theoretically the gold would have sunk, but floated on top of these and the nickel on top of the gold. So either not everything sunk to the core, stuff was brought back up to the surface from volcanism and other means, deposits formed afterward or all of these

My bad, BUT new stuff is arriving from space every day, and NOT just from within our solar system as most scientists seem to believe. We are bombarded by stuff from even beyond our galaxy.

[Deleted]

Jan 16, 2018 20:54:20 GMT -5 vegasjames said:

Makes some sense. It is well known that the gold is dissolved in supercritical water, which can form the deposits. So once the water is no longer in the suprecritical state it makes sense that the gold would "fall out". The only thing that does not make sense is where they talk about the water instantly vaporizing. Vaporizing to where? The water is within a closed space so unless the water is decomposing in to hydrogen and oxygen, which is highly unlikely, I just don't see it vaporizing as they claim.

Probably a non sciency writer not understanding"supercritical" water. Is all. I'm certain you are right.

[Deleted]

vegasjames

Here is a dilemma. Denser compounds will sink below less dense substances. So why did iron and nickel supposedly sink to the core but not the heavier elements like uranium, platinum, etc? Theoretically the gold would have sunk, but floated on top of these and the nickel on top of the gold. So either not everything sunk to the core, stuff was brought back up to the surface from volcanism and other means, deposits formed afterward or all of these

Perhaps we are saying the same thing and I am too dense to know it. Here is how I see it.

The earth formed and the dense stuff formed the core. New stuff came from space landed on the surface, and started sinking, but hasn't yet made the core (Answers your question above). So the mantle has the good stuff at all levels. Hydrothermal activity periodically brings upper mantle stuff back to the surface and deposits itself after a tremor (per the link above). Geologic activity moves that around (up?) until the prospectors find a new deposit.

Linguistically "deposit" is a perfectly apt description of the occurrence.

1dave

[vegasjames]

Jan 17, 2018 3:06:26 GMT -5 @shotgunner said:

@begasjames

Here is a dilemma. Denser compounds will sink below less dense substances. So why did iron and nickel supposedly sink to the core but not the heavier elements like uranium, platinum, etc? Theoretically the gold would have sunk, but floated on top of these and the nickel on top of the gold. So either not everything sunk to the core, stuff was brought back up to the surface from volcanism and other means, deposits formed afterward or all of these

Perhaps we are saying the same thing and I am too dense to know it. Here is how I see it.

The earth formed and the dense stuff formed the core. New stuff came from space landed on the surface, and started sinking, but hasn't yet made the core (Answers your question above). So the mantle has the good stuff at all levels. Hydrothermal activity periodically brings upper mantle stuff back to the surface and deposits itself after a tremor (per the link above). Geologic activity moves that around (up?) until the prospectors find a new deposit.

Linguistically "deposit" is a perfectly apt description of the occurrence.

1dave

I have always thought along the same lines with the material in the upper mantle simply getting brought back up to the surface. Again makes sense with volcanoes and we see that all the time with the mines out here that are located on thrust faults. These faults bring materials far under the ground above the surface.

But what about uranium deposits? I have never heard of any meteorites containing uranium.

[1dave]

Jan 17, 2018 5:42:16 GMT -5 vegasjames said:

But what about uranium deposits? I have never heard of any meteorites containing uranium.

THEY keep it simple: Irons, stones and stony-irons. In reality there are pages after pages of minerals found in meteorites like this:



Interesting to look at where minerals are found.

Gold and silver - mostly scattered over the west


Turquoise where there is copper - surrounding Utah


Uranium seems to be a late arrival !

[Deleted]

vegasjames said

But what about uranium deposits? I have never heard of any meteorites containing uranium.

That's ok. 6 months ago you weren't on board with anything but iron meteorites and a few rare stonies.

I'm sure science will find one. But keeping mind. That will be a vanishingly rare one.

[vegasjames]

Jan 17, 2018 9:30:48 GMT -5 1dave said:

Jan 17, 2018 5:42:16 GMT -5 vegasjames said:

But what about uranium deposits? I have never heard of any meteorites containing uranium.

THEY keep it simple: Irons, stones and stony-irons. In reality there are pages after pages of minerals found in meteorites like this:



Interesting to look at where minerals are found.

Gold and silver - mostly scattered over the west


Turquoise where there is copper - surrounding Utah


Uranium seems to be a late arrival !

You need to go to the next page to see if uranium is listed. It is not on those pages.

As fro the gold being concentrated in the West there are several explanations that could explain that. The main one would again be the high number of faults forcing the material above the previous surface. And there was all sorts of volcanic activity in the area, which also plays a role.

As for the turquoise this requires more than copper. It also requires an arid climate. Look at how much copper is coming out of Michigan yet I have never heard of turquoise coming out of Michigan mines.

[vegasjames]

Jan 17, 2018 10:33:37 GMT -5 @shotgunner said:

vegasjames said

But what about uranium deposits? I have never heard of any meteorites containing uranium.

That's ok. 6 months ago you weren't on board with anything but iron meteorites and a few rare stonies.

I'm sure science will find one. But keeping mind. That will be a vanishingly rare one.

What do you mean "6 months ago you weren't on board with anything but iron meteorites and a few rare stonies"?

There are several classifications of meteorites with NUMEROUS sub-classifications.

There has never been a radioactive meteorite found that I have heard of.  Some meteorites were formed from radioactive decay. For example there is an angrite consisting of enstatite that was formed from the radioactive decay of aluminum-26. But that had already stabilized.

[Deleted]

Sorry forest. I cannot see you. The trees are in the way.

1dave and I both are talking big picture. You are so caught up in minutiae.

Gold I am in agreement with you about faults, but there are plenty of nuggets too. Those are not water sourced.

Copper? He used turquoise as an example of copper in general. Had he used a map of copper mines map similar to the uranium mines one below your reply would be meaningless.

"Never a radioactive" meteorite? Who is looking? Possibilities dismissed out of hand because there has never been a radioactive meteorite. A self fulfilling prophecy.

We are discussing ideas and concepts, not checklists and microanalysis.

[vegasjames]

Jan 17, 2018 19:50:44 GMT -5 @shotgunner said:

Sorry forest. I cannot see you. The trees are in the way.

1dave and I both are talking big picture. You are so caught up in minutiae.

Gold I am in agreement with you about faults, but there are plenty of nuggets too. Those are not water sourced.

Copper? He used turquoise as an example of copper in general. Had he used a map of copper mines map similar to the uranium mines one below your reply would be meaningless.

"Never a radioactive" meteorite? Who is looking? Possibilities dismissed out of hand because there has never been a radioactive meteorite. A self fulfilling prophecy.

We are discussing ideas and concepts, not checklists and microanalysis.

Instead of posting personal attacks how about posting actual evidence to back your claims.

And actually yes gold nuggets are in fact water sourced.  Most gold nuggets are formed by bacteria in the water.  I learned that over 30 years ago so it is not some new, recent discovery.  The bacteria can form gold nuggets through several means. Bacillus cereus plates itself with gold believed to be for protection, and the process continues forming nuggets in the water. Other bacteria in water ingest the dissolved gold chloride killing the bacteria put producing a pure gold casting in the process. New bacteria adhere to the surface and the process repeats over and over forming nuggets in the water.  In fact if you look at a lot of gold and even some other metals like silver you will see beautiful patterns in them form the bacteria or silver for example can come in threads formed from filamentous bacteria.

And my comment about copper and turquoise is far from worthless.  Go back and read what was actually wrote.  Here let me help you. " Turquoise where there is copper - surrounding Utah".  Again my point is that it takes more than copper.  It requires an arid environment. That is why turquoise is not found everywhere copper is found. Catching on yet?

Who is looking? A LOT OF SCIENTISTS!!!!!  Meteorites are constantly being analyzed. Especially from Antarctica.  But labs analyze meteorites from all over. Ever hear of classification. For instance you will see names like Northwest Africa (NWA) 859, or Millbillillie.  The meteorites are almost always named after where they are found. But they are not given these names until they are classified. In order to be classified the meteorite or a sample of it has to be thoroughly analyzed, which among other things distinguishes the type of meteorite (carbonaceous chondrite, ordinary chondrite, howardite, plessitic iron, angrite, etc, etc, etc.).  They are also tested for things like mineral composition including radioactive isotopes, shock value, etc.

We are discussing a topic. If it is that far over your head then move on. Don't try to micromanage the information being presented or what can be said.

Read more: forum.rocktumblinghobby.com/post/975717/quote/81802#ixzz54UhZYeIM

[1dave]

Sorry, but I have to agree with @shotgunner. Page 306 DOES list Rhenium and Ruthenium, both of which are only manufactured in supernovas alongside Uranium, a large percentage of which has altered to Radon gas and Lead.

URANIUM: SUPERNOVA TO SUPER NUCLEAR
www.world-nuclear.org/opinion/cosmidx.htm
by Richard Arculus

. . .
Where did uranium come from?

Cosmochemists have been concerned not only with patterns and secular trends of abundance of the elements in galaxies but also with the origins of abundance anomalies in particular stars and with theories on the synthesis of different nuclei to account for these observations. According to the theories developed, the Earth's uranium was produced in one or more supernovae. The main process concerned was the rapid capture of neutrons on seed nuclei at rates greater than disintegration through radioactivity. The neutron fluxes required are believed to occur during the catastrophically explosive stellar events called suopernovae. Gravitational compression of iron (the island of nuclear stability, incapable of further exothermic fusion reactions) and sudden collapse in the centre of a massive star triggers the explosive ejection of much of the star into space, together with a flood of neutrons. Remnants of hundreds of supernovae have been found, and we "witnessed" one in the Magellanic Clouds in 1987.

So, we know that the earth's uranium was produced through this process in one or more supernovae, and that this material was inherited by the solar system of which the Earth is a part.

We might further ask how long ago this synthesis of uranium occurred. Given

* the present day abundances of U-235 and U-238 in the various 'shells' forming our planet,
* a knowledge of the half-lives of these isotopes, and
* the age of the Earth (c 4.55 billion years) - known from various radiometric 'clocks', including those of the uranium-to-lead decay chains,

we can calculate the abundances of U-235 and U-238 at the time the Earth was formed. Knowing further that the production ratio of U-235 to U-238 in a supernova is about 1.65, we can calculate that if all of the uranium now in the solar system were made in a single supernova, this event must have occurred some 6.5 billion years (6.5 Ga) ago.

This 'single stage' is, however, an oversimplification. In fact, multiple supernovae from over 6 billion to about 200 million years ago were involved. Additionally, studies of the isotopic abundances of elements, such as silicon and carbon in meteorites, have shown that more than ten separate stellar sources were involved in the genesis of solar system material. Thus the relative abundance of U-235 and U-238 at the time of formation of the solar system

* cannot be inverted to a 'single stage' model age,
* is essentially an accidental and unique value and
* reflects the input of the explosive debris of many progenitor stars.

Enrichment

Many analyses have been made of the uranium in the rocks forming the continental and oceanic crusts, and in samples of the Earth's mantle exposed as uplifted slices in mountain belts or as 'xenoliths' in basalts and kimberlites (hosts of diamonds).

We can have some confidence that these measurements are robust for the crust and upper mantle of the Earth, but less confidence that we know the abundance of uranium in the lower mantle and the outer and inner cores. While on average the abundance of uranium in meteorites is about 0.008 parts per million (gram/tonne), the abundance of uranium in the Earth's 'primitive mantle' - prior to the extraction of the continental crust - is 0.021 ppm. Allowing for the extraction of a core-forming iron-nickel alloy with no uranium (because of the characteristic of uranium which makes it combine more readily with minerals in crustal rocks rather than iron-rich ones), this still represents a roughly twofold enrichment in the materials forming the proto-Earth compared with average meteoritic materials.

The present-day abundance of uranium in the 'depleted' mantle exposed on the ocean floor is about 0.004 ppm. The continental crust, on the other hand, is relatively enriched in uranium at some 1.4 ppm. This represents a 70-fold enrichment compared with the primitive mantle. In fact, the uranium lost from the 'depleted' oceanic mantle is mostly sequestered in the continental crust.

It is likely that the process or processes which transferred uranium from the mantle to the continental crust are complex and multi-step. However, for at least the past 2 billion years they have involved:

* formation of oceanic crust and lithosphere through melting of the mantle at mid-ocean ridges
* migration of this oceanic lithosphere laterally to a site of plate consumption. (This is marked at the surface by a deep-sea trench)
* production of fluids and magmas from the downgoing (subducted) lithospheric plate and overriding mantle 'wedge' in these subduction zones
* transfer of these fluids/melts to the surface in zones of 'island arcs' (such as the Pacific's Ring of Fire)
* production of continental crust from these island arc protoliths, through remelting, granite formation and intra-crustal recycling.

All through this crust forming cycle, the lithophile character of uranium is manifest in the constancy of the potassium to uranium ratio at about 10,000 in the rock range from peridotite to granite. Because we would like to keep track of how uranium is distributed in the Earth, the abundance and isotopic characteristics of lead - the radiogenic daughter of U-235 and U-238 - are useful parameters. Table 1 below highlights the relatively low abundance of lead in the Earth's mantle and the consequent high uranium to lead ratio, compared with meteorites. The difference in abundance can most likely be explained by lead's volatile nature and tendency to combine with iron, with lead being lost during terrestrial accretion and core separation. One of the consequences, of course, of these high ratios is the comparatively high radiogenic/non-radiogenic content of Pb-207/Pb-204 and Pb-206/Pb-204 in the Earth's crust and mantle compared with meteorites or the earth's core. (Pb-207 is the final stable decay product of U-235, and Pb-206 is that of U-238. Pb-204 is non-radiogenic.)


U abundance - (ppm) Pb abundance (ppm) U/Pb ratio

Meteorites 0.008 2.470 0.003
Primitive mantle 0.021 0.185 0.113
Continental crust 1.4 12.6 0.111

Table 1

The figure given for the continental crust is an average of the entire crust. Of course, local concentration of uranium can far exceed these values, ranging up to 50 ppm, disseminated in some granites, to much higher values in ore deposits. In fact, in the geological past, local concentrations of uranium have occasionally achieved natural criticality, for example the Oklo reactors in Gabon.

. . .

There have been more supernovas since the formation of the solar system and the earth travels through them all every 225 million years. There is little doubt that there is more uranium out there headed our way.

[1dave]

A lot of energy is required to push magma a mile up through rocks.
Some mineral belts record up to 26 separate pulses.
What pressured the molten interior to hydraulically push it up?

Some could have come from earthquakes and continental collisions, but I believe the major impulses came from asteroid collisions.

The mineral belts are where interesting things happened.

General Observations:

1. Western States Mineral Belts follow inherited zones of weakness in Precambrian (Over 600 Million years old!)rocks that generally trend toward the northeast.
2. Major Intrusions and ore deposits tend to be widened at intersections of NE-trending belts with younger NW trending shear zones by emplacement of intrusions and localized ore-related hydrothermal activity.
3. Three major periods of mineralization have occurred about 32 million years apart:

65 mya - Late-Cretaceous-early Tertiary (major), time of the Chicxulub asteroid impact.
34 mya - Mid-Tertiary (major), time of the Popigai asteroid impact.
2.6 mya - Late-Tertiary (minor), time of the Kara-Kul asteroid impact/

Read more: forum.rocktumblinghobby.com/thread/64533/mineral-belts#ixzz54V5Ok8uk

[vegasjames]

Interesting article on the subject:

www.world-nuclear.org/information-library/nuclear-fuel-cycle/uranium-resources/the-cosmic-origins-of-uranium.aspx

And back on the subject of uranium in meteorites, if meteorites were the source of surface crust uranium then why is uranium not more widespread and more evenly distributed? And along the same lines if the Earth's iron also all sank to the core as hypothesized then why is iron so common on the Earth's crust. If this were also from meteorites then where is all the nickel that should also be present? Is it possible that not all the metals sunk to the core and instead when the earth was still molten the bubbling and other factors stirring the melt kept pushing these metals upward and as the melt became too viscous it prevented the metals from sinking and thus some of the metals got trapped in the upper layers that then cooled to a solid? It would be like when you boil a sauce the boiling is also stirring the mix so stuff at the bottom does get pushed up towards the surface. The sauce becomes viscous enough that it will not really separate and if cooled forms a hard crust with some of the heavier compounds in the sauce still trapped.

[Deleted]

I never ever make "personal attacks". If that is what you read, I can't help that, sorry. I suggested we were arguing vastly different perspectives of the same set of facts. One from a macro perspective and one from a microscopic perspective.

vegasjames I find you quite intelligent. I find you hard working and diligent. I find you persuasive. I would never attack your person. I never attack any person. Not my style. Oh, and you have good taste in dogs!

Regarding uranium?

I'll suggest that to have all those mines is easily explainable. Look at those mines as a strewn field pattern. A large fragile meteorite explodes and lands over that vast region with myriad landing points. Terrestrial chemistry changes the supernova remnants into what is mined today.

I always intend to offer new ideas and perspectives. Dogma sucks.

[Deleted]

Jan 16, 2018 21:10:29 GMT -5 1dave said:

Sorry, I don't buy it.

I can see gold, quartz and water coming form the top 100 km, but not through 5,000 km of iron from the core.

I think that you misinterpreted the article. I think the top X kilometres is the source of the hydrothermal gold. The crust origin of this gold being much older space rocks found deeper than newer ones. But not original formation materials. Bringing old space rocks to the surface through supercritical water chemistry.

I may be mistaken. Just a vision to share.

[1dave]

Jan 18, 2018 0:20:11 GMT -5 @shotgunner said:

Jan 16, 2018 21:10:29 GMT -5 1dave said:

Sorry, I don't buy it.

I can see gold, quartz and water coming form the top 100 km, but not through 5,000 km of iron from the core.

I think that you misinterpreted the article. I think the top X kilometres is the source of the hydrothermal gold. The crust origin of this gold being much older space rocks found deeper than newer ones. But not original formation materials. Bringing old space rocks to the surface through supercritical water chemistry.

I may be mistaken. Just a vision to share.

Yes, I didn't see the "crust" part.

Crust is mostly the lite elements, 90% hydrogen, oxygen, silicon, aluminum, iron, calcium, sodium, potassium, magnesium.