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

arxiv.org

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

#11

Post by api »

lmilcin wrote: post #5
hn_throwaway_99 wrote: post #3

I admit I did not read the entire publication, but, at least at face value, this seems somewhat absurd to me. Within the past couple hundred years humans have built massive structures in cities that should last for many millions (hundreds of millions?) of years. I mean, Manhattan may be under water in 100 million years (or, much sooner), but all those gigantic steel, concrete, plastic and glass structures aren't just…

There is better argument and it is surface natural resources. We know, that before industry took off we had huge amount of natural resources almost lying on the ground. Now many of crucial resources have to be dug from huge depths or recovered from dilute sources. I can't imagine a previous industrial civilization leaving huge amount of resources available on the surface. Almost by definition, industry is about scali…

Depends on time frame. Plate tectonics will reset things quite a bit over truly vast time scales.

Over shorter time scales this argument mostly holds, though one can imagine an intelligence with technology but with less expansionary drive and conspicuous consumption than humans. This intelligence may use resources more slowly.

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

#12

Post by ncmncm »

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 concrete will erode away. The radioactives will decay. It will all end up as a millimeter-thick layer on the sea bottom, one of thousands of millimeter-thick layers with nothing to call attention to itself. Microplastics will abound, but somebody needs to be looking for them in exactly that layer, the way we found iridium at the K-T boundary layer, after specifically looking. There is a huge overabundance of platinum (parts-per-billion) in layers only 12900 years old, just discovered in the past decade, and only because we are really interested in that layer. (It was the start of the 1300-year Younger Dryas cold spell whose end is the start of the Holocene Epoch.)

Will anything last? Big mining and quarry pits will fill in, but recognizably. Big mine tunnels will fill in or collapse, but recognizably. A rectangular mine shaft dug down through a thousand meters of sedimentary rock will have no other explanation.

Some structures will be buried, instead of eroding away. Those will be deep underground, and then might be exposed again through subsequent erosion or uplift. Again, a brick chimney found buried will have no other explanation, though people will try.

Strictly speaking, one is all you need, but some people ("people"?) need more convincing.

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

#13

Post by imglorp »

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…

Has anyone methodically looked for artificial materials like microplastics in the geological strata?

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

#14

Post by Retric »

imglorp wrote: post #13
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…

Has anyone methodically looked for artificial materials like microplastics in the geological strata?

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.

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

#15

Post by nabla9 »

hn_throwaway_99 wrote: post #3

I admit I did not read the entire publication, but, at least at face value, this seems somewhat absurd to me. Within the past couple hundred years humans have built massive structures in cities that should last for many millions (hundreds of millions?) of years. I mean, Manhattan may be under water in 100 million years (or, much sooner), but all those gigantic steel, concrete, plastic and glass structures aren't just…

In periods of 100s of millions of years whole continents disappear or move around, new layers of rocks are formed and old layers are buried. The Rocky Mountains formed just 55 - 80 million years ago.

Cities disappear completely. Concrete and glass becomes rock (again), steel is oxidized and is just layer of iron ore. Plastics degradate and breaks into nanoparticles.

As the article speculates, most evidence would be likely something like synthetic biomarkers in deep sea sediments. Traces of industrial chemicals not produced naturally. Wrong chirality in some organic chemicals. Transuranic elements.

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

#16

Post by tobinfricke »

Abstract: "If an industrial civilization had existed on Earth many millions of years prior to our own era, what traces would it have left and would they be detectable today? We summarize the likely geological fingerprint of the Anthropocene, and demonstrate that while clear, it will not differ greatly in many respects from other known events in the geological record. We then propose tests that could plausibly distinguish an industrial cause from an otherwise naturally occurring climate event."

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

#17

Post by saltedonion »

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…

Is total human/intelligent species population not a prerequisite for industrialization. If so, we would expect to see a lot of fossilized remains, which we have not seen.

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

#19

Post by DougWebb »

Retric wrote: post #14
imglorp wrote: post #13

Earlier quoted context omitted.

Has anyone methodically looked for artificial materials like microplastics in the geological strata?

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, quartz deposits, and ball lightning, which could be hinting at an energy source we haven't explored yet.

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

#20

Post by ffhhj »

A highly responsible civilization that achieves space fairing tech could rebuild its environment, leaving a clean planet as a gift for future species to emerge, and move to the stars. Sort of artifical-creationism, but phycally achievable, it's a matter of civilization goals.
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