The Pacific Ocean is without a doubt the world’s biggest ocean, more than 5 times broader than our moonWhy is the Pacific so huge?

Covering about 63 million square miles (163 million square kilometers)– more than 30 % of Earth’s surface area– all of the world’s continents might fit inside the Pacific basin, according to the National Oceanic and Atmospheric Administration(NOAA)The Pacific, which holds majority of the totally free water in the world, is likewise our world’s inmost water body, reaching a depth of more than 36,000 feet (11,000 meters) at Opposition Deep in the Mariana TrenchNOAA kept in mind.

The predecessor of the Pacific Ocean was Panthalassaor the Panthalassic Ocean, which was when Earth’s only ocean. This world-spanning superocean existed when all of Earth’s continental land was unified in the supercontinent Pangaea

“Panthalassa was the proto-Pacific,” Susanne Neuerestablishing director of the School of Ocean Futures at Arizona State University in Tempe, informed Live Science. “The Pacific is essentially what remains of Panthalassa.”

Oceans and continents previous and present rest on top of tectonic platesthe huge pieces of rock that comprise Earth’s stiff external shell. These plates are frequently on the relocation, often clashing into each other, often pulling apart from one another. About 230 million years back, such movements led Pangaea to begin separating.

“What became North America and Eurasia began to pull apart from what became South America and Africa and Antarctica and Australia,” Adriane Laman assistant teacher of Earth sciences at Binghamton University in New York, informed Live Science.

Related: Do the Pacific Ocean and the Atlantic Ocean blend?

Ultimately, Pangaea divided apart. In the space that emerged in between the continents, the Atlantic Ocean was born. “The Atlantic is growing about two to three centimeters each year, or about an inch,” Neuer stated. “That doesn’t sound like much, but when you multiply that by millions of years, it’s a lot.”

As the continents comprising Pangaea were pressed apart, Panthalassa diminished. At the “subduction zones” where these continental plates moved over Panthalassa’s oceanic plates, the “Ring of Fire” emerged, a zone notorious for volcanoes and earthquakes surrounding what is now the Pacific Ocean, Neuer described.

A 2016 research study in the journal Science Advances exposed that about 200 million years earlier, the Pacific Plate, the tectonic plate that now underlies the Pacific Ocean, was born at the junction of 3 tectonic plates under Panthalassa, called Farallon, Phoenix and Izanagi.

“The most modern analogy with what happened with the Pacific can be found today with the Afar triple junction in East Africa, where you have three plates meeting together — the Nubian, Somali and Arabian,” Lam stated. “But at the Afar triple junction, those plates ultimately failed to pull apart. With the Pacific triple junction, those three plates succeeded, forming the Pacific Plate.”

As the Pacific Plate broadened, it displaced these 3 older plates. The Izanagi Plate was pressed under Asia. Almost all of the Farallon Plate was driven underneath North America, although residues of it stay off North America’s west coast. And “the Phoenix Plate is nothing but a small piece between the southern tip of South America and the Antarctic Peninsula, the area of ocean called the Drake Passage,” Lam stated.

The Pacific is presently the world’s biggest ocean, “it’s getting smaller” as the Atlantic grows, Lam kept in mind. At 41 million square miles (106 million square kilometers), the Atlantic is still much smaller sized than the Pacific. And a 2024 modeling research study anticipates that the Atlantic will begin diminishing in about 20 million years.

For Lam, the Pacific Ocean is among a kind, she stated, noting its size, geological history and geological intricacy. “The Pacific is the most amazing ocean basin of all.”

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