The surprise about the largest ocean on Earth

The Pacific Ocean is now considered Earth's largest ocean, covering more than 30% of the planet's surface. However, this is only a "remnant" of what was once the largest ocean in the history of the Earth's formation. 

Illustration of the supercontinent Pangea and the vast ocean surrounding it.

According to Brendan Murphy, a professor of geology at the University of St. Francis Xavier (Canada), the largest ocean in history is called Panthalassa. This is a sea that stretches around the world, surrounding the supercontinent Pangea from about 300 million to 200 million years ago, the late Paleozoic and early Mesozoic.

"The largest oceans usually occur when supercontinents form. Because only when we have a supercontinent, there is an ocean around it," Murphy said.

This ocean included the (today) Pacific Ocean in the western and northern regions of the Tethys Sea. Later, Panthalassa became the Pacific Ocean, as a result of the closing of the Tethys Basin and the breakup of the continent of Pangea. For this reason, Panthalassa is often referred to as the Ancient-Pacific

In terms of surface area, Panthalassa makes the Pacific Ocean extremely small. This ocean covers about 70% of the Earth's surface, according to a report in the journal Earth-Science Reviews, with an estimated area of ​​360 million square kilometers. 

Interestingly, the Pacific Ocean will no longer be the largest ocean in the future.

According to geologists predicting the motion of tectonic plates, Australia will split the Pacific Ocean within the next 70 million years. With that, the Atlantic Ocean will expand, and eventually take the crown of Earth's largest ocean.