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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?

#81

Post by titzer »

kevin_thibedeau wrote: post #77
kadoban wrote: post #74

Earlier quoted context omitted.

You've provided a good argument that it's obvious _right now_ from our junk that we live here, but what of that do you expect to last, and how long? Pick a type of object or two and let's look into how they are expected to last and what they'll look like. Fossilization isn't a universal process, there's no such thing as a fossilized beer can.

Anything corrosion resistant that ends up entombed in geologically stable strata will stick around. There will be lots of anamolous ceramic and glass mixed in with the fossilized human bones strewn about.

Or even just leaves an imprint in the surrounding strata, but it itself does not survive.

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

#83

Post by vlovich123 »

treis wrote: post #76
yissp wrote: post #72

Earlier quoted context omitted.

I don't think satellites stay in orbit for very long - like a few decades at the very most.

Depends on their orbit. LEO will see drag from the atmosphere and will fall from orbit relatively quickly. Geostationary satellites will orbit basically forever.

Won’t solar winds push it out of orbit in a geologically relatively short amount of time?

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

#84

Post by nobody9999 »

phendrenad2 wrote: post #45
Animats wrote: post #41

The oldest hard-rock mountains are 1.5 billion to 3.5 billion years ago. Those include some heavily mined areas, such as the Appalachians, If a previous civilization had been into serious mining, we'd probably have seen evidence of that by now. There may be nothing left of the mine, but an area without the good stuff and the remains of a big rubble dump would be interesting. Conversely, a concentration of rusted meta…

Wouldn't metal dissolve over thousands of years? I'd be on the lookout for plastics.

> Wouldn't metal dissolve over thousands of years? I'd be on the lookout for plastics.

That's not a bad idea, but finding synthetic isotopes[0] with extremely long half-lifes[1] (e.g., Tellurium-128) would clinch the deal.

[0] https://en.wikipedia.org/wiki/Synthetic_radioisotope

[1] https://en.wikipedia.org/wiki/List_of_radioactive_nuclides_b...

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

#86

Post by Frost1x »

rbrbr wrote: post #57

Isn’t a much easier way to look around our planet and search for satellites of past civilizations? Or even on the moon where everything lasts much longer. Long after we and everything of us is gone from this planet moon vehicles and other devices which were left there will likely still be there unless a meteorite hit them.

I'd say the moon would be an obvious candidate to look at, though no guarantees.

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

#87

Post by timoth3y »

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.

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

#88

Post by neffy »

pmayrgundter wrote: post #43
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…

I strongly agree with this take. I've been working on a paper comparing the effects of the Anthropocene to mega catastrophes in the geologically recent past. In addition to the Younger Dryas Impact (12kya), there's the Oruani (26kya) and Mt Toba (77kya) eruptions. From my calculations, it seems the climate change from each of these dwarfs any actions humans are currently capable of, namely petrocarbon burning and als…

I think you're right, if you take the extreme events that have happened on this planet - and arguably the ice ages themselves also belong there, human activities haven't yet produced anything of that magnitude.

The question is how many more years do you want to give it until we do. These are huge slow systems we are looking at, at the point there is clear evidence around us that disaster is on the horizon, it is already several decades too late to do anything about it.

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

#89

Post by cgriswald »

ALittleLight wrote: post #70
jandrese wrote: post #38

Earlier quoted context omitted.

At one level yes, most everything built will disintegrate with time, but we have fossilized footprints from dinosaurs. An industrial society disappearing without a trace seems unlikely. Although the vast majority of the evidence would be lost there will always be traces left if you know what to look for.

The dinosaurs lived for a couple hundred million years. An industrialized society might last a few thousand.

You'd want to compare the total number of dinosaurs that ever lived against the number of fossil-izable and recognizable artifacts an industrialized society ever created.

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

#90

Post by monkeydreams »

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.

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