Earth has eight continents, and world maps should reflect this, geologists say.
The continent you’ve probably never heard of, It’s called Zealandia, and it’s almost totally covered in ocean water. The tiny bit of land that peeks above the ocean’s surface is what we know as New Zealand, but the landmass that New Zealand is a part of is much, much larger than we see on most maps.
On Monday, researchers from GNS Science in New Zealand announced that they’d mapped the shape and size of the continent in unprecedented detail. They put their maps on an interactive website so that users could virtually explore the continent.
Researchers thought it was ultimately submerged beneath the Pacific Ocean, a little over 20 million years ago, after it broke off from the supercontinent Gondwana around 80 million years back. A report in New Atlas claims that with New Zealand and New Caledonia as its only two above-water landmasses, Zealandia is around one-third smaller than the continent of Australia.
Zealandia’s total area has been mapped to be nearly 2 million square miles (5 million square kilometers). At this measure, Zealandia is about half the size of Australia, however, only 6% of the continent is above sea level.
The part above water forms the foundation of New Zealand’s north and south islands as well as the island of New Caledonia. The rest of Zealandia is underwater and thus had to be mapped for its ocean floor too, hence a bathymetric map.
“Their value is that they provide a fresh context in which to explain and understand the setting of New Zealand’s volcanoes, plate boundary and sedimentary basins,” Dr. Mortimer says.
There are three versions of the map data available to view right from your browser. There’s a geoscience map, a tectonic map, and a bathymetry map. The tectonic one is interesting because it reveals how the major faults affected the shape of the submerged continent, but the bathymetry map is probably your best bet if you want to dream of what the continent might look like if it were above sea level.
The Earth is constantly changing. It’s a slow process, but the arrangement of the continents that we see today is a far cry from what they were 100 million years ago. Go back even farther and you’ll find all the continents mashed together into the supercontinent Pangea. If things shook out a bit differently, Zealandia might have ended up being a bustling continent instead of a submerged landmass.