Epic Travel → Asia & the South Pacific → New Zealand → Otago → Moeraki Boulders

Location: East Coast, Otago, New Zealand

Time Required: 1 hour

Red Tape/Notes: Best to visit at mid-tide or lower to have the best exploration and viewing opportunities.

What’s Nearby?: Oamaru

The Moeraki Boulders are easy to get to and worth stopping for, even if they’re likely to be a little crowded. We got lucky and had no crowds (this seems to happen to us a lot! Hooray!) but they are well-known, so don’t expect to have them to yourself. If there are crowds, you’ll probably escape them if you stray more than 5 minutes from the main cluster of boulders. This is nice, because if you walk down Moeraki Beach to the cliff face, you can actually see erosion unveiling more boulders. The boulders aren’t unique (similar ones have been found in many countries) but they are certainly picturesque. What are they? Well, basically they’re weird rock spheres on a beach.

Oh, you wanted a more scientific explanation? Um…I’m not a geologist so I’m poorly equipped for this kind of thing, but technically the boulders are concretions. Basically a little baby boulder formed in marine mud near the surface of the sea floor, and then calcium precipitated out of the mud and hardened in the spaces between the mud particles and on the surface of the baby boulder (effectively creating a “cement” that hardened the shape). The round shape occurs because the calcium “cement” source was mass diffusion, rather than fluid flow (which would have created an irregular shape). At some point, large cracks appeared in the boulders (these are actually called septaria, and the precise cause is unknown) and were slowly filled with (mainly) brown and yellow calcite. The boulders are harder than the sediment in which they’re encased, so as erosion occurs, the sediment disappears and the boulders are revealed.

Sometimes I hear people saying that they’re fossilized dinosaur eggs. This is not true, although if I had children I would be sorely tempted to pretend. Although if you want real dinosaur time capsules, head down towards Shag Point to see the similar Katiki boulders (make sure you go at half tide or lower, or else you’ll just see water). The main difference between the Katiki and Moeraki Boulders is that many of the Katiki boulders were actually formed around fossils, including an 8m (yes, 8 meter!) Plesiosaur now on display at the Otago Museum in Dunedin.

Epic Travel → Asia & the South Pacific → New Zealand → Otago → Moeraki Boulders