Continents rise above the waves
Land stops being scattered islands and starts being continents with coastlines.
- When
- Known to
- ± 150 million years
- Era
- Neoarchean, Archean
Around the Mesoarchean–Neoarchean transition, continental crust becomes thick enough to stand widely above sea level, and emergence continues gradually over the following 500 million years. Exposed rock weathers, delivering phosphorus and other nutrients to the sea, and shallow continental shelves appear — the very settings where cyanobacteria thrive. Rising land and rising oxygen are probably not a coincidence.