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Would it be possible to detect an industrial civilization in geological record?

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Re: Would it be possible to detect an industrial civilization in geological record?

#111

Post by oh_sigh »

timoth3y wrote: post #87

It more convincing to look at it the other way. It's not what such civilizations would have left, but what they would have taken. Our early civilizations found easily accessible deposits or tin, copper, gold, etc that would have been depleted if another advanced civilization had existed in the past 10 million years or so.

Tin was actually very hard to find. Which is a huge problem for civilizations that wanted to be a part of the Bronze age. Most of the tin used in Europe and western Asia was mined from just a few places in England, France, and Spain. if you find an Assyrian weapon from the 12th century BC in northern Iraq, it shouldn't surprise you if you find it was forged with tin mined in Cornwall.

Re: Would it be possible to detect an industrial civilization in geological record?

#112

Post by m4rtink »

samatman wrote: post #102
tsomctl wrote: post #99

Earlier quoted context omitted.

I don't think so. Landfills are a source of many important minerals and energy. I'm convinced that we'll be mining ours in the next couple of centuries.

Maybe, but if so, it will be because we have really substantially depleted primary mines. A precursor civilization which needed to mine its landfills would therefore undoubtedly have left a visible scar in the fossil record. If they suffered some calamity before getting to that point, then we get landfillite. Either way, I think we'd see evidence of any civilization which sustained the equivalent of a 19th and 20th c…

Not necessarily just due to depletion - could be just better technology (eq. some massive robotics deployment, gassification & atomic sorting, etc.) that makes it a no-brainer to process all regular waste & the old ones when you are at it.

Even modern waste incineration comming quite close with iron & even alluminium collected from the slag & the mostly inert reminder reused in consturction. The local waste incineration plant already covers all district heat requirements of the 400k people city in the summer and is poised to cover 50% of the inter load once their new nr. 3 furnace is installed.

Re: Would it be possible to detect an industrial civilization in geological record?

#113

Post by josephagoss »

revnode wrote: post #48
jack_pp wrote: post #37

Earlier quoted context omitted.

So a civilization thousands years more advanced than us failed to go to space (evidenced by the fact that they did not leave behind any space junk) but somehow produced energy from crystals?

> evidenced by the fact that they did not leave behind any space junk Whatever space junk we leave behind will be gone 100 years from now. https://www.nasa.gov/news/debris_faq.html

I think that’s just for lower orbits, I was under the impression our geosynchronous satellites will be up there for millions of years (unless future humanity cleans up the geosynchronous graveyard orbit)

Re: Would it be possible to detect an industrial civilization in geological record?

#114

Post by teslaberry »

the real question is , what kind of technologies and how much effort do you assume we would have to detect it?

if a time traveller came to us, from the past , into the present ( which is possible if they discovered near speed of light travel) ---and they told us that an amazing civilization used to exist 300,000 years ago and they told us to spend billlions of dollars and tons of effort to look for it. i think we could accomplish that, especially if it were an international collaboration. now, if only a few academic anthropoligists in a few limited yet presitigoius universities were sent on missions to find it, we'd have much less of a chance. ---everything is probabilities. so the real question is, how much persuading would it take, to make enough people interested, as a collective, to raise the probability to become very likely.....what if some snake oil salesman told you he was from 300,000 years ago and travelled at .98c and slowed down to reach the present while everyone else died. how much 'proof' of that trip, would he need to covincne you to abandon your life now to become indiana jones, or to spend $5,000 of your savings on his non-profit search committee.

Re: Would it be possible to detect an industrial civilization in geological record?

#115

Post by m4rtink »

vbezhenar wrote: post #24
DougWebb wrote: post #19

Earlier quoted context omitted.

That's true about the oil; coal too. If we're not completely wrong about how those resources are created (there are some alternate theories) then we're the first civilization to use them. However, most of what I've read about prehistoric advanced civilizations discussed them using crystals (quartz) and deriving energy from the earth. Some form of piezoelectricity. There are theories today connecting earth quakes, qua…

We sent humans to space and robots to Mars and other planets, we are extracting energy from nuclear fission, we will likely build an artificial star soon enough. It's extremely unlikely that we could have missed some mysterious quartz power source.

That's all nice and dandy until aggressive aliens wielding muskets show up in wood & brass starship: https://en.wikipedia.org/wiki/The_Road_Not_Taken_(short_stor...

Re: Would it be possible to detect an industrial civilization in geological record?

#116

Post by m4rtink »

Retric wrote: post #59
revnode wrote: post #48

Earlier quoted context omitted.

> evidenced by the fact that they did not leave behind any space junk Whatever space junk we leave behind will be gone 100 years from now. https://www.nasa.gov/news/debris_faq.html

That’s really not what that means. The 4th satellite Vanguard 1 was put into orbit in 1964 and it’s expected to have a 240-year orbital lifetime despite getting to within 657.3 kilometers of earth. https://en.wikipedia.org/wiki/Vanguard_1 Geosynchronous satellites 35,786 km (22,236 mi) are going to be up there for a very long time. PS: If you’re interested https://aiaa.kavi.com/apps/group_public/download.php/3172/IS.…

And anything that went to solar orbit will be the more or less for ever, subject only to the slow erosion of thermal cycles over the eons. And all Pioneers, Voyagers and New Horizons will not have to sustain even that, just comic rays.

BTW, it's a bit mind boggling how big and empty even just interplanetary space is - there could be wrecks of an unlucky discovery fleet paying a visit couple milion years ago and we might never find them unless they come really close to Earth or other sensor rich human inhabitted place or possibly still produce some active emissions (outgassing, sporadic radio signals, abnormal heat absorption/radiation, weird albedo variations, etc.).

Re: Would it be possible to detect an industrial civilization in geological record?

#117

Post by lumost »

jlawson wrote: post #109
pmiller2 wrote: post #22

Earlier quoted context omitted.

Those people need to watch a few episodes of the TV series Life After People . Watching it, and realizing that everything around us would literally start to fail in a matter of days without us as its caretakers, really brought home the impermanence of everything. Skyscrapers are certainly not going to outlast ancient cave dwellings. In a matter of a couple hundred years, I would be surprised if a single skyscraper wa…

I wonder how long the Egyptian pyramids would last.

As the pyramids are constructed of limestone, they would desolve during the next wet phase of the sahara ( previous wet period ~20kya and 12.5 kya ).

https://en.wikipedia.org/wiki/Sahara_pump_theory

Re: Would it be possible to detect an industrial civilization in geological record?

#118

Post by hdjdbtbgwjsn »

ncmncm wrote: post #64
Retric wrote: post #56

Earlier quoted context omitted.

Oil is useful for a lot more than just burning it. Fertilizers, plastics, and asphalt are the most well known but a host of industrial processes use it as a feedstock. It’s only recently that oil has been hard to find, initially it was seeping up from the ground which still occurs on the sea floor in some areas making it hard to miss. So some other civilization could exist without using it, but they would look nothin…

It is one thing to use it, entirely another to exhaust it. A civilization consuming only 1% as much could look very similar, if it were not dependent on oil for fuel.

We don't need to exhaust it. We only need to exhaust the easy to find sources.

Re: Would it be possible to detect an industrial civilization in geological record?

#119

Post by LargoLasskhyfv »

DougWebb wrote: post #19
Retric wrote: post #14

Earlier quoted context omitted.

Yes, in that people try and identify what’s there. No, in that it’s not expected to find evidence of a prior advanced civilization. The prior existence of oil as an easily recoverable resource is a strong indicator that nothing like our civilization existed in the last several million years.

That's true about the oil; coal too. If we're not completely wrong about how those resources are created (there are some alternate theories) then we're the first civilization to use them. However, most of what I've read about prehistoric advanced civilizations discussed them using crystals (quartz) and deriving energy from the earth. Some form of piezoelectricity. There are theories today connecting earth quakes, qua…

There is the hypthecial concept of a https://en.wikipedia.org/wiki/Nuclear_lightbulb which pending some so far unavailable metamaterial would reach temperatures of up to 20,000°C and generate mostly hard UV-light in a closed cycle.

Which reminds me of some decsriptions of Indian Vimanas, or rather the parts about their engines, which allegedly were made of some crystals.

Re: Would it be possible to detect an industrial civilization in geological record?

#120

Post by dwaltrip »

bwood wrote: post #91
withinboredom wrote: post #66

Earlier quoted context omitted.

The thing is, it’s probably unbelievable when you do find evidence. https://archaeology-world.com/200-million-year-old-shoe-prin...

Interesting article, but unfortunately none of it is verifiable. It cites creationism.org (!!!) as a source and concludes that the fossil shoeprint is regrettably lost.

> It cites creationism.org (!!!)

Ouch... that's an enormous red flag. That irrecoverably tarnishes the entire article.

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