Question

How did Earth’s first oceans form?

Answer 1

Earth's first oceans formed over 4 billion years ago from volcanic outgassing and water delivery from comets and asteroids, providing a habitat for the earliest forms of life.

Step-by-step explanation:

Earth's first oceans formed over 4 billion years ago as the planet cooled from its original molten state. After the formation of a solid crust, volcanoes began releasing gases, contributing to the creation of an early atmosphere rich in water vapor, as well as other gases like ammonia, methane, and carbon dioxide. As the planet cooled further, cloud formation and subsequent rainfall occurred, leading to the accumulation of water on Earth's surface, creating the primordial oceans.

Additionally, scientists believe that comets and asteroids carrying water could have struck Earth, further contributing to the development of the oceans. Over time, the early oceans set the stage for the origins of life, despite being toxic to today's life forms. This led to the evolution of life, such as cyanobacteria, which began to produce oxygen, eventually transforming Earth's atmosphere and environment. Thus, Earth's first oceans were not just vast bodies of water, but also cradles for the emergence of life.

Answer 2

Scientists think that over time, all these collisions filled the oceans. Another idea is that ocean water came from deep inside the earth. It was brought to the surface when volcanoes erupted. Scientists think soon after the earth was formed, there was a long period of massive volcanic eruptions.