Zealandia, a submerged landmass surrounding New Zealand and New Caledonia, has been fully mapped after decades of geological research.This achievement completes the documentation of its nearly two million square miles, revealing it as Earth’s eighth continent.

The study, published in *Tectonics*, highlights how sedimentary basins, seismic imaging, and rock samples from the Fairway Ridge to the Coral Sea have helped decode Zealandia's complex history.

Once part of Gondwana, the ancient supercontinent that included Australia and Antarctica, Zealandia broke away around 80 million years ago but sank under the ocean, leaving only 5% above water.

Researchers found evidence of Late Cretaceous sandstone (95 million years old) and Eocene basaltic lava (40 million years old), shedding light on its tectonic evolution.The mapping also revealed how Zealandia's separation from Gondwana involved stretching and thinning of the crust, creating the Tasman Sea.

Recent studies emphasize that Zealandia’s geological story is far more intricate than previously thought, with ongoing research focusing on sedimentary basins and post-rift features.This work not only clarifies Zealandia’s past but also informs modern geohazards, resources, and environmental understanding.