In a new study published in the journal Nature Geoscience in March 2020, scientists showed evidence that the Earth was completely covered by the ocean, without the land 3.2 billion years ago, similar to the scene from Kevin Costner's movie "Waterworld" made public in 1995.

Photo: Shutterstock.

Benjamin Johnson, a researcher at the University of Iowa and his collaborator Boswell Wing at the University of Colorado Boulder (USA) conduct a geological survey of the Panorama region (Australia) - which stores an ancient ocean crust and traces of a hydrothermal system.

After analyzing the concentrations of the two oxygen-16, and oxygen-18 isotopes in 100 sediment samples, they discovered that the original ocean's 3.2 billion years ago contained more isotopes of oxygen-18 than oxygen-16. [oxy-16 is more common in modern oceans].

Computer simulations show that on a global scale, land masses are capable of absorbing oxygen-18 from the ocean. In the absence of continents, the ocean will carry more oxygen-18. The ratio of the two oxygen isotopes in the study implies that at the beginning, the Earth did not have any continent.

After the long period of time, the tectonic plates collided, pushing huge blocks of rock up to form the continents.