Source: Science Daily
Precambrian cratons — some of Earth’s oldest rocks — were uninhabitable for microbes for much of their existence, with the longest period of habitability not much beyond a billion years, and many only for the past 50 million to 300 million years, according to a paper correlating Earth’s deep biosphere with geologic history.
https://www.sciencedaily.com/releases/2021/11/211102111213.htm
