The Pacific tectonic plate

The Earth's surface is made up of a series of large plates like pieces of a giant jigsaw puzzle. These plates are called tectonic plates. We have been talking about volcanoes and earthquakes and mountains throughout this blog - the reason why there is a lot of activity in New Zealand is because two tectonic plates meet along the island:

The Southern Alps on the South Island are formed by tectonic uplifting and pressure as the Pacific and Australia-Indian plates collide along the island's western coast. The uplifting continues, raising the mountain range an average of 7 mm (just over a quarter of an inch) each year. However, erosive forces are also constant shapers of the mountains. Wind, rain (and ice!) and dramatic changes in temperature are reducing the mountains by about the same amount.

The Southern Alps has the highest mountain in NZ, Mount Cook, which stands at 3,754 metres (12,316 ft). (And, as a powerful example of the erosion forces at work, Mount Cook was 10 m (33 ft) higher until approximately 10 million cubic metres of rock and ice fell off the northern peak in 1991).
More info available at the Moorland School website.