Here's a quick geography quiz. How many continents are there?

There's Africa, Asia, Antarctica, Australia, Europe, and North and South America. So, seven. Some prefer to group Asia and Europe together as Eurasia, so six is also an acceptable answer.

But what about Zealandia? It's not that a new continent suddenly formed.

In fact, Zealandia has been around for millions of years. It's only recently that geologists have been able to make the case for it.

Where It Is

Off the eastern coast of Australia there are the island chains of New Zealand and New Caledonia. It turns out those islands are actually part of the same landmass, about the size of India, although most of it is underwater.

Continent Criteria

Zealandia does still meet the criteria for a continent.

It's elevated above the surrounding area, it has at least three types of rocks common to other continents, and that are older than the surrounding ocean floor; it's a well‑defined area; and it has a thicker, less dense type of crust compared to the ocean floor.

This finding, while scientifically interesting, could also have political and economic implications in terms of rights to offshore mineral and fossil fuel resources in the region.

Thank you to Bruce Luyendyk of the University of California, Santa Barbara for reviewing this episode.

Sources And Further Reading:

• Byrd, Deborah. "Scientists spy 8th continent, Zealandia." EarthSky. February 22, 2017. Accessed May 31, 2017.

• Witze, Alexandra. "Geologists spy an eighth continent: Zealandia." Nature, 2017. doi:10.1038/nature.2017.21503