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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?

#121

Post by ncmncm »

monkeydreams wrote: post #90
user4682 wrote: post #73

There are changes in the geological record that are still unexplained, these could be signs of an older civilization.ld "The Younger Dryas was a period of rapid cooling in the late Pleistocene 12,800 to 11,500 calendar years ago. It followed closely on the heels of a dramatically abrupt warming that brought the last Ice Age to a close (17,500 calendar years ago), lasted for about 1,300 years, then ended as abruptly a…

You are posting a climate-change denying site as your source for this? Consider me incredulous. Edit: From my quick perusal, the warming for the Younger Dryas period is not mysterious at all. The main theory is that there was a sudden cooling due to the failure of the Atlantic meridional overturning circulation around 12,900 BC. This cooling was then rapidly reversed back to the median warming trend about 11,700BC.

You have just pushed the mystery back a step. What caused the failure of the Atlantic meridional overturning circulation? What reversed the failure 1200-odd years later?

Evidence for a bolide strike producing a huge meltwater pulse, to start the process, is accumulating, coinciding with extinction of 30+ genera and the sudden end of the Clovis culture. Another strike at the Holocene boundary is less well supported; but we do need a cause.

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

#123

Post by filoeleven »

One of my favorite quotes from Iain M. banks’ Culture series, paraphrased here since I don’t recall which book it’s in, is that technological progress is more like scaling a rock face than climbing a ladder. There is so much room for surprise and incomprehension.

I sometimes think about how vast the parameter space of our physical universe is, and if that vastness means we wouldn’t be able to recognize ancient advanced technology if it’s far enough outside of our current mode of progress.

My favorite example is handing an SD card with all of Wikipedia and the Gutenberg Project and maybe even the Wayback Machine on it to a Roman emperor. He’d look at it and might have a mild interest in the geometrical metal bits on an otherwise insignificant tiny flake of weird material. If the deliverer were to tell him that it contained millions of documents, he wouldn’t believe it.

An expert in the field of storage media could, if for some reason permitted, spend years trying to explain it to the scholars of the time. Even if the expert succeeded in convincing them, it would take an unimaginable effort lasting lifetimes to ever make use of the thing. It would not succeed. Not because those people were stupid, but because the specialization that’s needed to understand the artifact is so far away from from their cultural knowledge and capabilities as to be unreachable. Why should we expect our culture be any different?

The primary counter-argument to this is math and physics, and it’s a pretty strong one. It holds up quite well when dealing with past civilizations that are beneath or somewhere close to our current level of understanding. If you’ll permit another flight of fancy though, imagine an ancient society that figured out how to encode information in the irregularities of crystalline structures: every lame-ass quartz medallion we’ve unearthed could be the equivalent of a 10TB hard drive, and we’d never be the wiser.

I think this is pretty unlikely, but it’s good to be humble and interrogate your assumptions.

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

#124

Post by JoeAltmaier »

jccooper wrote: post #95

Yes, over geologic time, nearly anything has no chance of survival. And, yes, the lifetime of such a civilization may be a window that is, geologically, basically invisible. But an industrial civilization makes a LOT of stuff, and much of that is quite durable and easily recognizable as artificial, and is likely to be scattered all over the planet. Given that there are places that preserve tracks over 300 million yea…

It wouldn't take a complex material to recognize a previous civilization. Their civil engineering activities would give them away completely.

Archaeologists can read worked surfaces with amazing skill. E.g. a bed of pebbles could be a lake bed, a road surface, a floor inside a building, a foundation, and there's ways to distinguish them.

Unless the soil was erased/reformed completely there would be a record of almost any activity, from digging a post hole or trench, to building a wall then removing it again then dumping construction waste into the hole then plowing it under. All are different from 'native' soils deposited by random processes.

Geologic time is not enough to erase evidence of worked soils. Not unless it gets scrubbed to the bedrock and redeposited. And even if that happened some places, it wouldn't happen every place. And its fair to say today, that our civilization has been pretty much every place.

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

#125

Post by nitwit005 »

ksdale wrote: post #92
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.

"Depleted" in this case would just mean mined, transported, and made into something. It doesn't seem farfetched to imagine that, say, an electronics factory would be reduced to an easily accessible deposit of copper or gold in a few million years.

It depends how long the civilization is around. A lot of metal could end up impractical to mine. You can recycle metals, but little chips are being lost to wear and corrosion over time. We're slowly spreading small amounts everywhere.

Some of that would be theoretically be recoverable with a lot of effort and energy, but some of it will basically be gone. No one is going to get back small bits of metal fallen off ships into the deep ocean.

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

#126

Post by reachfortheskyy »

pmiller2 wrote: post #22
ncmncm wrote: post #12

Every time this pops up on HN, people post insisting that it won't all go away, that the skyscrapers will, somehow, still be there. No, they won't. Look at any place in the world where there are mesas. All of the land around the mesa used to be level with the top of the mesa. It has all eroded away, and in only a few million years. So, the metals will corrode, collapse, and wash away. The stone will erode away. The c…

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…

For what it's worth, the Spivey Building is almost 100 years old and it's been abandoned since the '50s.

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

St. Louis has a lot of cool abandoned architecture, although you might want to be careful wandering around East of the river.

I wonder how many cities have abandoned towers that became historical places thanks to longstanding traditions of not being able to afford a demolition.

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

#127

Post by sjy »

I’m never sure whether to trust arXiv papers outside my field, so I checked and found that the paper was published in the International Journal of Astrobiology, and the PDF is open access: https://www.cambridge.org/core/journals/international-journa...

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

#128

Post by sjy »

jccooper wrote: post #95

Yes, over geologic time, nearly anything has no chance of survival. And, yes, the lifetime of such a civilization may be a window that is, geologically, basically invisible. But an industrial civilization makes a LOT of stuff, and much of that is quite durable and easily recognizable as artificial, and is likely to be scattered all over the planet. Given that there are places that preserve tracks over 300 million yea…

The paper addresses this objection in section 1.3: “That this paper’s title question is worth posing is a function of the incompleteness of the geological record … The oldest extant large-scale surface is in the Negev Desert and is ~1.8 Ma old. However, pre-Quaternary land-evidence is far sparser, existing mainly in exposed sections, drilling and mining operations. In the ocean sediments, due to the recycling of ocean crust, there only exists sediment evidence for periods that post-date the Jurassic (~170 Ma).”

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

#129

Post by 8bitsrule »

There have been many civilizations on Earth, maybe not many were industrial (ancient Egypt was clearly semi-industrial so far as lithic tooling is concerned.)

We haven't looked deep enough very much. Many of the 10-25,000 year sites are buried dozens of feet underground. If there are any previous ruins, they're probably a hundred-or-more feet down. Seaside ruins from 10k+ years ago are now under 400 feet of water and 10k+ years of sediment. We've just started to notice evidence of major changes only 13k years back ... with more on the way.

Over 100,000 years, water has scoured (and deeply buried) much of the surface. Consider the number of glaciations in the past 2M years ... each one of which has scoured the surface in northern regions repeatedly. Much farther back than that, and most geo- and bio-records are erased.

The planet's dynamics would have scrubbed almost anything before 10 million years ago. There've been 400 of those; 5 major extinctions left some traces. The scale of upheavals has been massive. How long ago did the Andes arise? It was first noticed in the 1700s that Whole sections of the Earth's surface have gone missing. https://en.wikipedia.org/wiki/Hutton%27s_Unconformity

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

#130

Post by sjy »

JoeAltmaier wrote: post #124
jccooper wrote: post #95

Yes, over geologic time, nearly anything has no chance of survival. And, yes, the lifetime of such a civilization may be a window that is, geologically, basically invisible. But an industrial civilization makes a LOT of stuff, and much of that is quite durable and easily recognizable as artificial, and is likely to be scattered all over the planet. Given that there are places that preserve tracks over 300 million yea…

It wouldn't take a complex material to recognize a previous civilization. Their civil engineering activities would give them away completely. Archaeologists can read worked surfaces with amazing skill. E.g. a bed of pebbles could be a lake bed, a road surface, a floor inside a building, a foundation, and there's ways to distinguish them. Unless the soil was erased/reformed completely there would be a record of almost…

Geologic time is certainly enough to erase evidence of worked soils. It spans billions of years, the destruction and formation of continents, and multiple global mass extinctions. Archaeology concerns only the last few million years of hominid activity.
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