العربية
中国
Français
Deutsch
Ελληνική
हिन्दी
Italiano
日本語
Português
Русский
EspañolMAAR
(Redirected from Maar lake)
A 'maar' is a broad, low relief crater that is caused by a phreatic eruption or explosion caused by groundwater contact with hot lava or magma. The maar typically fills with water to form a relatively shallow crater lake. The name comes from a local German dialect of Daun, which is in turn derived from Latin ''mare'' (sea). Maars are shallow, flat-floored craters that scientists interpret have formed above diatremes as a result of a violent expansion of magmatic gas or steam; deep erosion of a maar presumably would expose a diatreme. Maars range in size from to across and from to deep, and most are commonly filled with water to form natural lakes. Most maars have low rims composed of a mixture of loose fragments of volcanic rocks and rocks torn from the walls of the diatreme.
Maars occur in the western United States, in the Eifel region of Germany, where they were originally described, and in other geologically young volcanic regions of the world. Kilbourne Hole and Hunt's Hole, near El Paso, Texas, are maars. The notorious, carbon dioxide saturated, Lake Nyos in Cameroun, Africa is another example. An excellent example of a maar is Zuni Salt Lake in New Mexico, a shallow saline lake that occupies a flat-floored crater about across and deep. Its low rim is composed of loose pieces of basaltic lava and wallrocks (sandstone, shale, limestone) of the underlying diatreme, as well as random chunks of ancient crystalline rocks blasted upward from great depths.
★ USGS Photo glossary of volcano terms: Maar
★ USGS: Maars and Tuff Cones
★ Morale Claim Maar, Arizona
The three maars near Daun - Link to Wikimapia: http://wikimapia.org/#y=50175057&x=6844783&z=15&l=0&m=h&v=2
A 'maar' is a broad, low relief crater that is caused by a phreatic eruption or explosion caused by groundwater contact with hot lava or magma. The maar typically fills with water to form a relatively shallow crater lake. The name comes from a local German dialect of Daun, which is in turn derived from Latin ''mare'' (sea). Maars are shallow, flat-floored craters that scientists interpret have formed above diatremes as a result of a violent expansion of magmatic gas or steam; deep erosion of a maar presumably would expose a diatreme. Maars range in size from to across and from to deep, and most are commonly filled with water to form natural lakes. Most maars have low rims composed of a mixture of loose fragments of volcanic rocks and rocks torn from the walls of the diatreme.
Maars occur in the western United States, in the Eifel region of Germany, where they were originally described, and in other geologically young volcanic regions of the world. Kilbourne Hole and Hunt's Hole, near El Paso, Texas, are maars. The notorious, carbon dioxide saturated, Lake Nyos in Cameroun, Africa is another example. An excellent example of a maar is Zuni Salt Lake in New Mexico, a shallow saline lake that occupies a flat-floored crater about across and deep. Its low rim is composed of loose pieces of basaltic lava and wallrocks (sandstone, shale, limestone) of the underlying diatreme, as well as random chunks of ancient crystalline rocks blasted upward from great depths.
| Contents |
| References |
| External links |
References
★ USGS Photo glossary of volcano terms: Maar
★ USGS: Maars and Tuff Cones
External links
★ Morale Claim Maar, Arizona
Weinfelder Maar, one of the three maars originally described
This article provided by Wikipedia. To edit the contents of this article, click here for original source.
psst.. try this: add to faves
