Early Earth May Have Been Covered In Water
One of the many films that actor Kevin Costner has been in was called "Waterworld" and while the film didn't do well in the box office, it did give a look at what an early Earth might have looked like. New research from the University of Colorado, Boulder has been published that shows the Earth may have been completely covered in water 3.2 billion years ago.
The scientists on the project took advantage of a quirk of hydrothermal chemistry to suggest that the surface of Earth was covered by a global ocean. Researchers on the project think that its findings might help scientists to better understand how and where single-cell organisms first emerged on Earth.
Researcher Boswell Wing says that the history of the planet tracks available niches. He says that if the world is covered by an ocean, dry niches aren't going to be available. The team says that the study also gives an idea of what an ancient Earth may have looked like when the planet was much hotter than it is today. The researchers went to a place called the Panorama district in the Northwestern Australia outback.
The location has a 3.2-billion-year-old chunk of ocean crust that is on its side. Scientist say that the location allows you to walk in a day from the base of the crust to the spots where water once bubbled up through the seafloor via hydrothermal vents. In the formation are rocks that interacted with seawater and remember the interaction.
More than 100 rocks samples around the terrain were analyzed. They were looking for isotopes of oxygen trapped inside the stones with one being Oxygen-18 and the other Oxygen-16. Findings suggest that there was a bit more Oxygen-18 in the seawater on ancient Earth than we see today hinting at much less landmass. Earth today is covered in clay-rich soils that disproportionally take up Oxygen-18. The team says that ancient Earth could have micro-continents sticking out of the ocean, but they don't believe the continents as we know today could have existed. The team plans to investigate other rock formations around the world for additional clues.