Science girl
@sciencegirl
Scientists have confirmed that Zealandia is a genuine continent hidden mostly beneath the South Pacific Ocean. Spanning around 5 million square kilometres (nearly 2 million square miles), only a small portion of it sits above sea level today, including islands such as New Zealand. For years, researchers argued over whether the region was simply scattered pieces of continental crust or a single connected landmass. New geological evidence now supports the idea that Zealandia meets the criteria of a continent, with a distinct crust, defined boundaries, and a shared geological history. Scientists believe Zealandia separated from the ancient supercontinent Gondwana roughly 85 million years ago. As tectonic activity stretched and thinned the crust, most of the land gradually sank below the ocean surface while still remaining geologically connected. To better understand the region, researchers studied rock samples collected from the seafloor, including sandstone, basalt, and volcanic material dating back millions of years. They combined this with magnetic data from the ocean crust, which revealed matching geological patterns across the submerged landmass. These magnetic signatures helped scientists trace Zealandia’s full extent and confirmed it is far more than isolated underwater fragments. Instead, it represents a large, unified continent shaped by volcanic processes and shifting tectonic plates over vast stretches of time. Because so much of Zealandia has remained underwater for millions of years, researchers say it offers a rare opportunity to study how continents evolve, fracture, and sink beneath the sea, processes that are often difficult to observe on exposed land. The findings are reshaping how scientists view Earth’s geology and suggest that major parts of our planet may still remain hidden beneath the oceans. Read the study: "Reconnaissance Basement Geology and Tectonics of North Zealandia." Tectonics.