Moeraki Boulders at KoeKohe Beach





These  Moeraki Boulders are unusually large and spherical boulders lying along a stretch of Koekohe Beach. We started our road trip on the Otago coast heading north of Dunedin. The boulders are scattered either as a single rock or clusters  within a stretch of beach where they have been protected in a scientific reserve. The erosion from wave action hitting the mudstone exposed embedded boulders. These boulders are grey-colored septarian concretions.
Local Māori legends explained the boulders as the remains of eel baskets washed ashore from the wreck of an Arai-te-uru, a large sailing canoe. This legend tells of the rocky shoals that extend seaward from Shag Point as being the petrified hull of this wreck and a nearby rocky promontory as being the body of the canoe's captain. (sited from http://en.wikipedia.org/wiki/Moeraki_Boulders)

Amazing! The most striking aspect of the boulders is their unusually large size and highly spherical shape, with a distinct bimodal size distribution. About one-third of the boulders range in size from about 0.5 to 1.0 metres (1.5 to 3 ft) in diameter, the other two-thirds from 1.5 to 2.2 metres (4.6 to 6.7 ft), the majority being nearly to almost perfectly spherical. A minority of them are not spherical, being slightly elongated parallel to the bedding of the mudstone that once enclosed them. (http://en.wikipedia.org/wiki/Moeraki_Boulders)

Ellie trys to get on top

Alex Chills out on Beach

Jen on Top!

John and Ellie

family photo

Ellie balancing on Moeraki Boulders



These amazing Moeraki Boulders were created by a process similar to the formation of oyster pearls, where layers of material cover a central nucleus or core.
For the oyster, this core is an irritating grain of sand. For the boulders, it was a fossil shell, bone fragment, or piece of wood. Lime minerals in the sea accumulated on the core over time, and the concretion grew into perfectly spherical shapes up to three metres in diameter.