Curious geological phenomenon

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The Maori call New Zealand, Aotearoa which means “The land of the long white cloud”.

New Zealand is located in Oceania, in the South Pacific Ocean.

The official languages in New Zealand are English and Maori.The Capital city of New Zealand is Wellington, located on the North Island.

Moeraki, on the east coast of the South Island, south of Oamaru, is known world wide for its famous boulders. The boulders formed over millions of years, but Moeraki has a human history only a few hundred years old.

The Moeraki Spheres are huge spherical stones that are scattered over the sandy beaches, but they are not like ordinary round boulders that have been shaped by rivers and pounding seas. These boulders are classed as septarian concretions, and were formed in ancient sea floor sediments.

They 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 meters in diameter.

The original mudstone seabed has since been uplifted to form coastal cliffs. Erosion of the cliffs has released the three ton captive boulders, which now lie in a haphazard jumble across the beach.

Further erosion in the atmosphere has exposed a network of veins, which gives the boulders the appearance of turtle shells. Similar boulders occur at Shag Point, and the nearby swimming beach of Katiki.

In Hawke’s Bay in the North Island, scientists have found that the central core of similar boulders contained perfectly preserved skeletons of turtles, sea snails and extinct reptiles, such as plesiosaurs.

Scattered along the beach at Moeraki which is some 40 kilometers south of Oamaru, the boulders are a popular visitor attraction. The soft mudstone containing the boulders was raised from the sea bed around 15 million years ago and sea erosion of the cliff is exposing the erosion-resistant boulders.

Emerging from the cliff, as if being born from the earth, the World famous Moeraki Boulders are septerian concretions formed some 65 million years ago. Crystallization of calcium and carbonates around charged particles in muddy undersea sediments gradually formed the boulders in a process taking as long as four million years.

According to Maori legend, the origin of the boulders dates from the loss of the Arai-te-uru, one of the large sailing canoes that came from distant Hawaiki. On her quest south for the precious greenstone, the canoe was wrecked near Shag Point (Matakaea).

The reef which today extends seawards is the canoe's petrified hull, while close by, in the shape of a prominent rock, stands the petrified body of her commander.

Strewn along the beach are the boulders which represent the eel baskets, calabashes, and kumaras washed ashore from the wreck. The name Moeraki (Moerangi) means “drowsy day”.

So, this history goes back as far as the legendary Arai-te-uru canoe, wrecked along the coast while searching for the precious stone of Te Wai Pounamu.

Moeraki makes a fascinating stopover point, both for the dramatic coastal scenery and the curious geological phenomenon on the beaches.

Moeraki has a long history of Maori occupation, which is represented in the town today by the Kotahitanga Maori Church and a pa site nearby. This small seaport town was the first European settlement in North Otago.

Behind the town a road leads to the lighthouse where you can find a yellow-eyed penguin sanctuary and a seal colony. There are other walks of ecological interest around the coast, and through the Trotter’s Gorge native forest. South of Moeraki is the town of Palmerston, where you can follow an historical scenic route to Central Otago.

Sound: Te Vaka - Lelei ilo tenei (better than this)

Te Vaka - Sei Malelosa

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Arangement: Sanda Foişoreanuwww.slideshare.net/michaelasanda