How did the Moeraki Boulders form?

Strange, spherical boulders scattered on the sand…

On this beach located in New Zealand, these unusual rocks, measuring between 50 cm and 2 meters in diameter and weighing up to several tons, have long been a source of intrigue. Fossilized dinosaur eggs, relics of Maori ancestors, the work of extraterrestrials…

They have inspired many legends. But science has finally solved the mystery: the formation of these rocks began approximately 60 million years ago. Fossilized clay and mud are found in the center, around which sediments such as calcite have accumulated. One layer at a time, the boulders grew larger over the years. The concept is similar to the formation of an oyster pearl. Several hypotheses that may explain the spherical shape of these rocks exist, such as tidal action, gravity, and the pressure that the layers of sediment exert on each other. These are the Moeraki Boulders, one of the most iconic landscapes in New Zealand.

Brut.