How did it appear?

Mar 14, 2008 14:04 GMT  ·  By

This is an unique and wild landscape, characterized by chaotic rocks, sharp volcanic cones and coniferous forests surrounding the highest lake in the Cascades Mountains, the deepest lake in US (589 m or 1,963 ft) and the seventh in the world: Crater Lake.

It is located in southern Oregon, in a volcanic region. The lake occupies an area of 5,438 hectares (21 square mi), having a diameter of 10 km (6 mi) and being located at an altitude of 2,673 m (8,910 ft). The lake received its name in 1869 because of a small crater topping the Wizard peak, the only island of the lake. The area was declared National Park in 1902.

How did the lake appear? Once the Muzama Mountain, an active volcano, was located in this location. The height of Muzama was of 3,592 m (11,973 ft). 7,700 years ago, the volcano erupted with a force 42 times higher than that of the eruption of St Helens in 1980. The resulting ash was spread over 8 US states and 3 Canadian provinces, covering a surface of 12.949 ha (52 square km) with an ash layer 15.24 cm (6 in) thick. In the Pumice Desert, located close to the Crater Lake, the ash layer reached a length of 15 m (50 ft).

The explosion caused a volcanic caldera (crater), appeared after the crumbling of the upper part of the volcano and the forming of a gap in its interior. At the beginning, the bottom of the caldera was too hot to allow the gathering of water. The volcanic activity continued even after this explosion, forming a volcano cone (the Wizard peak) in the middle of the crater (a volcano inside a volcano!).

Gradually, the volcanic activity decreased and 4,000 years ago, water coming from melting snow and rainfall collected in the caldera, forming the Crater Lake. The Crater lake is famous because of its special blue color.

The beauty and clearness of these water harbor a close, fragile ecosystem. The Crater Lake National Park harbors over 52 species of mammals, 250 species of birds and 570 species of plants (trees included).

Between 1888-1941, the waters of the lake were populated with various species of fish, but today only the rainbow trout (Oncorhynchus mykiss) and kokanee salmon (Oncorhynchus nerka) survive.