World’s consumption of materials hits record 100bn tonnes a year

Re:World’s consumption of materials hits record 100bn tonnes... by clmul on Wednesday January 22, 2020 @01:55PM (#22120726)

Assuming the dirt weighs about 2 tons per cubic meter, this corresponds to 58 kg/m^2 / 2000 kg/m^3 =~ 0.03 m, so it seems like the gp just used the incorrect unit.

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Re:World’s consumption of materials hits record 100bn tonnes... by njarboe on Wednesday January 22, 2020 @03:59PM (#22121964)

You are correct. I had 1000000000 as a trillion. Scientific notation is a much better way to calculate things. At 30mm that is a big enough layer that a geologist could see it in the rock record, if it looked different enough.

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Re:World’s consumption of materials hits record 100bn tonnes... by thfuran on Thursday January 23, 2020 @01:48PM (#22130430)

I believe that we've spewed enough radiation that no visual distinction would necessary for detection, at least for the next several tens of thousands of years.

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Re:World’s consumption of materials hits record 100bn tonnes... by titzer on Thursday January 23, 2020 @05:21PM (#22132911)

It's true that atmospheric nuclear testing has produced trace elements that were basically never on Earth before 1945, like Strontium-90 [https://en.wikipedia.org/wiki/Strontium-90]. Strontium-90 has a half life of about 29 years, so it will be detectable for a few thousand years or so. Some others last longer.

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