Crater Lake
Crater Lake
Crater Lake is a crater lake of Mount Mazama volcano in the south of the state of Oregon in the United States. Crater Lake is the central object of Crater Lake National Park and is distinguished by its unusually deep blue color. The lake was created by the filling of the caldera with rainwater. The amount of water exchanged from approximately every 250 years.
Water
The Crater Lake ³ has a volume of 17.46 km a deep blue and clear water. The lake has no additions or outflows. The water is from rain and snow melt water. The water quality is the best in all of North America. 1972 was measured with the Secchischeibe a visual depth of 144 feet ( 43.9 m); this is one of the greatest values that have ever been measured. In 1997, a visibility depth of 142 feet ( 43.3 m) was measured. The pH is 7 to 8, the preservation of water quality is given by the Park Administration major importance. The circulating on the lake motorboats have completed a fuel system so that no traces of oil get into the water.
Dimensions
The water surface has a height of 1883 m above sea level and an area of 53.2 km ². The shoreline measures 35.1 km. The lake has a horizontal spread of 8 by 9.6 km and an average depth of 350 m, the deepest point is 594 m. It is the deepest lake in the country and the second deepest in North America.
Geology
The former is part of the volcanic arc of the Cascade Range.
The hitherto most recent eruption was about 7700 years ago, the exact date is disputed. Recent analyzes are based on
- 5724 ± 20 cal BC, calibrated with CalPal from 6845 C- 14y Before Present; or
- 5677 ± 150 cal BC.
The super massive eruption reached a value of 7 on the Vulkanexplosivitätsindex and had ³ a material discharge of 150 km. The result was that the dome of the volcano collapsed and today's caldera formed. Between 88 and 224 million tons of aerosols into the atmosphere and caused the northern hemisphere for a temperature decrease of about 0.6 ° C. Also, the ozone layer became noticeably pulled by the outbreak affected.
It was followed by further eruptions, for example, the central platform, Wizard Iceland, Merriam Cone, and other surveys in the lake formed. The hydrothermal activity at the bottom of the lake is an indication of a possible repeated eruption of the volcano.
There are two islands: Iceland Wizard ( " Wizard Island " ) and Phantom Ship Iceland ( " Ghost Ship Island "). Wizard Iceland has a height of 230 m at mean water level and an area of 1.278 km ². Iceland Wizard is itself a small ( inactive ) volcano that formed about 4600 BC. The Merriam Cone is an elevation below the water surface.
Others
The lake had over time following other names: Deep Blue Lake, Blue Lake and Lake Majesty. As the lake had no original fish population, various fish were exposed from 1888 to 1941. Based in the vicinity of the Klamath people ( Indians) worships the Crater Lake today as a sacred site.
Pictures
Geology
The lake in winter with views of Iceland Wizard
State Quarter 2005
Panorama of Crater Lake