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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?

#71

Post by analyte123 »

ChuckMcM wrote: post #65
nraynaud wrote: post #58

Earlier quoted context omitted.

The meteorites we find fell “recently”? The iron is in a stable oxide?

I don't think so, meteoric iron (according to the wonderful blog series[1]) is early Egyptian. Iron (and steel) is stable outside the presence of oxygen and water. It doesn't just dissolve. And certainly if it were part of the steel reinforcement inside concrete in a building where special measures had been taken to insure that neither oxygen nor water would come in contact with it (as modern skyscrapers do) would pe…

What about when the skyscraper’s pieces are submerged under saltwater for a million years? Or are covered up by a mile of river sediment and then plunged another 5 miles under the earth for several million years?

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

#72

Post by yissp »

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

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

#73

Post by user4682 »

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 as it started. The cause of these remarkably sudden climate changes has puzzled geologists and climatologists for decades and despite much effort to find the answer, can still only be considered enigmatic."

https://wattsupwiththat.com/2012/06/19/the-intriguing-proble...

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

#74

Post by kadoban »

titzer wrote: post #67

FTA: "The likelihood of objects surviving and being discovered is similarly unlikely. Zalasiewicz (2009)speculates about preservation of objects or their forms, but the current area of urbanization isless than 1% of the Earth’s surface (Schneider et al., 2009), and exposed sections and drillingsites for pre-Quaternary surfaces are orders of magnitude less as fractions of the original surface.Note that even for early…

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.

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

#75

Post by Andrew_nenakhov »

titzer wrote: post #67

FTA: "The likelihood of objects surviving and being discovered is similarly unlikely. Zalasiewicz (2009)speculates about preservation of objects or their forms, but the current area of urbanization isless than 1% of the Earth’s surface (Schneider et al., 2009), and exposed sections and drillingsites for pre-Quaternary surfaces are orders of magnitude less as fractions of the original surface.Note that even for early…

Thing is, unlike dinosaur bones, beer can or bottle can't survive for aeons.

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

#76

Post by treis »

yissp wrote: post #72
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 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.

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

#77

Post by kevin_thibedeau »

kadoban wrote: post #74
titzer wrote: post #67

FTA: "The likelihood of objects surviving and being discovered is similarly unlikely. Zalasiewicz (2009)speculates about preservation of objects or their forms, but the current area of urbanization isless than 1% of the Earth’s surface (Schneider et al., 2009), and exposed sections and drillingsites for pre-Quaternary surfaces are orders of magnitude less as fractions of the original surface.Note that even for early…

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.

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

#78

Post by opportune »

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?

We know about the KT extinction layer (which contains a lot of iridium, a potentially extremely useful but rare metal) but attribute it to meteorite ejecta. It also coincided with large scale climate and environmental changes. That's the only candidate I know of as a non-geologist.

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

#79

Post by metiscus »

Andrew_nenakhov wrote: post #75
titzer wrote: post #67

FTA: "The likelihood of objects surviving and being discovered is similarly unlikely. Zalasiewicz (2009)speculates about preservation of objects or their forms, but the current area of urbanization isless than 1% of the Earth’s surface (Schneider et al., 2009), and exposed sections and drillingsites for pre-Quaternary surfaces are orders of magnitude less as fractions of the original surface.Note that even for early…

Thing is, unlike dinosaur bones, beer can or bottle can't survive for aeons.

but styrofoam lasts forever /s

For sufficiently short values of forever.

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

#80

Post by titzer »

Andrew_nenakhov wrote: post #75
titzer wrote: post #67

FTA: "The likelihood of objects surviving and being discovered is similarly unlikely. Zalasiewicz (2009)speculates about preservation of objects or their forms, but the current area of urbanization isless than 1% of the Earth’s surface (Schneider et al., 2009), and exposed sections and drillingsites for pre-Quaternary surfaces are orders of magnitude less as fractions of the original surface.Note that even for early…

Thing is, unlike dinosaur bones, beer can or bottle can't survive for aeons.

Sure they can, if surrounded by stable strata in the same way that dinosaur bones were. In fact, beer cans can bottles won't be broken down by natural biotic processes; they just need to be protected from erosive forces.
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