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This question is a result of recent news that Earth had a "boring billion" years in which mountains ceased to grow, and subsequently hindered life evolution.

The article went on to give extraordinary details the scientists have provided. They know that the Earth's mountains were not growing anymore, the crust was then thinning, and the ocean life couldn't get nutrients to help evolution.

There was also a recent animation of Earth's tectonic plates over their lifetime and how the continents shaped into what they are now.

How did they know all that stuff? How did they know the tectonic plate moved from here to here a few billion years ago? Or how mountains no longer grow, or, or, or...

I understand the concept of carbon-dating, and that's about it. Are there are any other crazy methods that enable them to make these mind-blowing measurements?

I don't mind a detailed, jargon-filled explanation, but hopefully it can still make sense to someone generally interested in Science like myself.

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  • $\begingroup$ One thing is certain: It is not carbon dating. That only works for items that are 50000 years old, or younger. $\endgroup$ Feb 12, 2021 at 2:55
  • $\begingroup$ You should link your sources. There is a Boring_Billion wiki.Also Plate reconstruction. $\endgroup$ Feb 12, 2021 at 3:46

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How on “Earth” can you make all those measurements of Earth forming?

One word: Zircons.

Zircons rank very high amongst the techniques used to measure the age of the Earth, and the age at which the Earth later cooled down. One of the key elements in zircons is zirconium. There are other elements that have similar chemical characteristics to zirconium. One of these is uranium. Both uranium 235 and uranium 238 eventually decay to lead. Lead is extremely incompatible with zirconium from a chemical perspective. All of the lead in a zircon could only have resulted from radioactive decay.

The question focuses on the "boring billion" years in the Earth's history that occurred well after the Earth formed (over three billion years after the Earth formed). Zircons were key in that analysis as well. There are other elements other than uranium that are chemically compatible with zirconium. One of these is europium. The presence or absence of europium in zircons indicates whether or not mountains were eroding at the time those zircons formed. The ratio of uranium to lead in those zircons indicates how old those zircons are.

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