Oceans began to form about 3.8 billion years ago (3800 million years ago). This formation occurred during the early Archean Eon, shortly after the Earth itself formed about 4.54 billion years ago. The early oceans formed as the Earth cooled below the boiling point of water, allowing water vapor in the atmosphere to condense and fall as rain, filling the basins on the Earth's surface and creating the first stable bodies of liquid water.
Among the options provided:
- 12 million years ago (mya) is too recent.
- 137 mya is also too recent.
- 2 mya is far too recent.
- 3800 mya (3.8 billion years ago) is the correct answer.
