Tramping in Tongariro National Park

New Zealand is home to numerous mountains that form the backbone of both the North and the South Island. During our visit to the North Island we stopped in Tongariro National Park where we tramped around some of the mountain ranges that are home to the highest peak in the North Island, Mount Ruapehu, at an elevation of 2,797 m (9,176 ft). Mount Ruapehu, is an active statovolcano, also called a composite volcano, is a tall, conical volcano with many layers (strata) of hardened lava, tephra, and volcanic ash. Stratovolcanoes are characterized by a steep profile and periodic, explosive eruptions. The lava that flows from stratovolcanoes tends to be viscous; it cools and hardens before spreading far. The magma forming this lava is often felsic, having high-to-intermediate levels of silica (as in rhyolite, dacite, or andesite). Mt. Ruapehu is largely composed of andesite and began erupting at least 250,000 years ago. In recorded history, major eruptions have been about 50 years apart, in 1895, 1945 and 1995–1996. Minor eruptions are frequent, with at least 60 since 1945. This recent activity is due to the country's position on the boundary between the Indo-Australian and Pacific Plates, a part of the Pacific Ring of Fire. During these hikes we stumbled upon streams that were coming off the mountain ranges that look much different from the streams back in Minnesota, I was curious to why the rivers had beds of orange. I soon discovered that this coloration was due to minerals these minerals that are iron- rich form precipitates that cover the rock beds in the rivers and stream associated with some springs on the andesitic volcanoes. These iron rich minerals after oxidization can cause the rocks to assume and orange or brown rusty color. These colored deposits are iron-oxide clays from upstream swamps. The heavy rain in the area tumbles over the ancient and newly formed lava flows and then makes its way to the rivers and streams that lace the mountain sides, further up the mountain when the stream emerges from the lava cliffs at the head of the valley the water is rich in aluminium and silicate minerals. These volcanic formed streams do not seem to affect the growing vegetation surrounding these areas. As we were walking I examined many different types of vegetative life such as wire rush, tangle fern, red tussock and beech trees that surround and shade the areas.