Putangirua Pinnacles facts for kids
The Putangirua Pinnacles (officially Pūtangirua Pinnacles) are amazing rock formations in New Zealand. People often just call them "The Pinnacles." They are a great example of something called badlands erosion.
These pinnacles are like tall, skinny earth pillars. Geologists call them hoodoos. You can find them at the end of a valley in the Aorangi Ranges. This area is on the North Island of New Zealand, in the Wellington region.
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How the Pinnacles Formed
Millions of Years Ago
About 7 to 9 million years ago, the land where the Pinnacles now stand was an island. Sea levels were much higher back then. As the island slowly wore away, large piles of rock and dirt formed. These piles are called alluvial fans. They built up on the island's southern beaches.
Later, the sea level rose again. This caused the island to go underwater. The alluvial fans were covered by the ocean.
The Ice Ages and Erosion
After the ice ages, sea levels dropped again. This exposed the old alluvial fans to the weather. Wind and water started to wear away the rock. This rock is a type called conglomerate. It is made of many different rocks cemented together.
In some spots, a harder cap of cemented silt or rock protected the conglomerate. This harder cap stopped the erosion underneath it. Over time, the softer rock around it washed away. This created the tall, spectacular pinnacles we see today.
How They Change Today
Many pinnacles have grooves on their sides. These grooves are called fluting. They are made by rainwater running down the rocks during big storms.
Scientists think the pinnacles are less than 125,000 years old. The main erosion probably started about 7,000 years ago. It sped up in the last 1,000 years. This was due to trees being cut down in the area. The pinnacles are still changing today. They are eroding at about 1 centimeter (0.4 inches) per year.
The Pinnacles in Movies
The Putangirua Pinnacles are so unique, they have been used in movies! Part of the famous film The Lord of the Rings: The Return of the King was filmed here. This was for the "Paths of the Dead" sequence.
The opening scene of the movie Braindead was also filmed at the Pinnacles.
Official Name
In December 2019, the official name for these rocks was made public. It is now "Pūtangirua Pinnacles."
