3.24 billion years ago, when the Solar System was 1.32 billion years old, is in the "Archaean" era pre-Cambria. We have some constraints now on what this planet looked like. The New York Post offers a translation for lower Zones Of Thought.
The original essay argues that the isotope ratios from 3.24 bya indicate oxygen, but an alien sort of oxygen. It was being emitted but not taken back in (UPDATE April: plants are later). Bacterial life wasn't all that effective; oxygen mainly would have been taken in by weathering, which can be spotted in old rocks as well. The oldest rocks are in Australia, South Africa, Antarctica (to the extent that ever gets drilled into), and Quebec. There wasn't much weathering in Australia, at least.
The essay concludes that continents and mountains were mostly underwater at this time (at least, Australia was). The article explains that for dummies: WATER WORLD!!
It's not unanticipated. Later comes the famous Snowball Earth / "Cryogenian" interval. I always figured the Earth would need a lot of water to come up with the amount of ice for the projected albedo. Admittedly I never ran the maths myself.
A better question is: where did the water go. Maybe the continents rose up in tandem with the seafloor sinking down. Maybe the young Earth's poor radiation-protection allowed water breakup and hydrogen escape - like on Venus today.
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