Final answer:
Oceans began to form on Earth about 4.4 to 4.57 billion years ago. The process involved the gradual formation of the atmosphere followed by the accumulation of water.
Step-by-step explanation:
The formation of oceans on Earth began about 4.4 to 4.57 billion years ago. Initially, Earth was molten and lacked an atmosphere and oceans. Over time, the atmosphere formed, followed by the accumulation of water to create the oceans.
For example: Fossil evidence suggests that multicellular organisms existed about 700 million years ago, indicating the presence of bodies of water.
Another example: The presence of stromatolites, which are colonial cyanobacteria, provides evidence of the existence of oceans around 3.5 billion years ago.