October 19, 2010 - South Island, New Zealand

South Island, New Zealand

Spring in New Zealand unfurls like the spiraling frond of the native silver fern, which expands in shades of greens and tan, with touches of silver. This fern, called koru by the Maori, symbolizes new life and is a fitting symbol for October, when the South Island brushes off winter by unfurling shades of dark green in the forests, light green in agricultural land and tans in the rugged mountains and foothills, all highlighted by the silvery-white gleam of the snow clinging to the tops of the Southern Alps.

On October 11, 2010, when this true-color image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra satellite, the stark beauty of the land was enhanced by cobalt blue waters of the Tasman Sea and the Pacific Ocean, and by swirls of milky turquoise of phytoplankton in the coastal waters.

Although the scene is peaceful, New Zealand’s land is restless. Here two large tectonic plates, the Australian Plate and the Pacific Plate, slowly and relentlessly collide. The pressure of this collision is released in complex ways, creating fracture zones, trenches and high mountains. Earthquakes are common – a 7.0 earthquake struck the east coast near Christchurch on September 3, 2010. Volcanic activity also occurs on North Island, the shore of which can be seen in the upper right corner of this image.

The southwest corner of South Island, called Fiordland, is a series of massive cuts carved by glaciers during successive ice ages. The scenery is dramatic – towering, snow capped mountain peaks, ancient forests, and midnight blue ocean inlets – but the real drama is the tectonic activity. To the south of Fiordland, the Australian Plate is being forced beneath (subducted) the Pacific Plate at the Puysegur Trench, which is more than 5,000 meters (16,404 feet) deep. To the north, the enormous pressure of two massive plates of Earth in collision raises the sharp ridges of the Southern Alps.

Image Facts
Satellite: Terra
Date Acquired: 10/11/2010
Resolutions: 1km ( B), 500m ( B), 250m ( B)
Bands Used: 1,4,3
Image Credit: Jeff Schmaltz, MODIS Land Rapid Response Team, NASA GSFC