What happens during this time?
Continents as we know them today, with continental plates and plate tectonics appear
Subduction zones, continental plates sliding over each other, and upwelling of lava to produce new crust where continental plates tore apart
Continents grow by getting lighter and tougher.
Cyclic re-melting and reformation of rock through lava flows (igneous differentiation) gradually separates the lighter minerals, and allows the development of felsic rocks from mafic rocks.
Lighter rocks are more buoyant, and resist recycling by floating over the liquid mantle.
The supercontinent Kenorland formed during the beginning of this period (~2.7 Ga)
Methane gas is prominent, and oxygen mostly absent from the atmosphere
Subduction zones could have been a vital factor in the early oxygenation of the Earth (Meng et al. 2022)
Oceans were probably green from rust, a ferrous–ferric hydroxy salt (Halevy et al. 2017)
Evidence for the origin of oxygen-forming photosynthesis
Sulfur and molybdenum levels increased in the oceans around this time
The simultaneous increase of both indicates that microbes on land may have been breaking down rock, which washed into the sea.
Above: World map around 2.7 Ga, with supercontinent Kenorland