Today’s Wonder of the Day was inspired by Olivia. Olivia Wonders, “What is Zealandia?” Thanks for WONDERing with us, Olivia!
Can you name the continents of the world? You may have learned them in school. Some kids even sing a song about their names. Can you help us name them all? There’s North America, South America, and Africa. We know Asia, Australia, and Europe. What’s the last one? Oh yeah—Antarctica!
But there may be a continent missing from that list. Or, at least, some experts think there is. That’s right, Earth may have an eighth continent. Don’t believe us? Just keep reading! Today, we’re talking about the underwater continent of Zealandia.
Are you WONDERing how a continent could be underwater? You’re not alone! After all, all the other continents are on dry land. Geologists have many reasons to call Zealandia a continent. One is its elevation. It’s very high above the ocean floor. In fact, it’s only about two-thirds of a mile below the surface. To compare, the deepest part of the ocean is nearly seven miles down.
Zealandia’s geology is also like that of continents. That means the rocks and minerals found there are a lot like those on land. Experts have also studied the crust below Zealandia. They say it’s very much like the crust of continents. It’s very different from the crust below the ocean floor.
And of course, Zealandia wasn’t always underwater. Long ago, it was on land. It was part of Pangaea. That changed when it broke away from Antarctica and then Australia. That’s when about 94 percent of Zealandia came to be underwater between 80 and 100 million years ago. Later, Zealandia sank further due to activity from the Pacific Ring of Fire.
Today, only a small part of Zealandia is above sea level. This includes the islands of New Zealand and New Caledonia. The underwater portion is about two-thirds of a mile below the surface. All-in-all, Zealandia is about 1.9 million square miles. That’s roughly the size of the Indian subcontinent.
Further, experts don’t think of Zealandia as part of Australia. That’s because they sit on different tectonic plates. This is another reason they say Zealandia is its own continent.
Experts also believe that plants and animals once used Zealandia to cross the Pacific. The team that went to Zealandia found fossils from hundreds of species. Many of these are known to live in shallow water near Australia and New Zealand. This led experts to think many species likely crossed Zealandia when it was under shallow water.
Will Zealandia one day be named the Earth’s eighth continent? Possibly. Until then, scientists have more to learn about it. Would you like to explore the waters of Zealandia? What might you find there? You never know what could be waiting to be discovered!
Standards: C3.D2.Geo.10, CCRA.R.4, CCRA.L.3, CCRA.L.6, CCRA.R.1, CCRA.R.2, CCRA.W.4, CCRA.W.7, CCRA.SL.1, CCRA.R.10, CCRA.W.1, CCRA.W.9, CCRA.L.1, CCRA.L.2, CCRA.SL.2