A volcanic crater that is produced by an explosion in an area of low relief, is generally more or less circular, and often contains a lake, pond, or marsh.
A type of monogenetic volcano, generally formed by subterranean phreatic or phreatomagmatic eruptions that occur as magma explosively interacts with ground water or subsurface moisture. Maar craters are cut into the surrounding country rock, vary from 10-500 meters deep, and range from a few hundred meters to 3 km in diameter. Maar volcanoes are generally surrounded by low, shallowly outward-dipping beds of well-bedded volcanic ejecta that rapidly decrease in thickness away from the vent. The volcanic deposits are mainly emplaced by base surges and fallout, and commonly contain very little (or in the case of phreatic eruptions, no) juvenile volcanic materials (Vespermann and Schminke, 2000, p. 685: Cas and Wright, 1987, p. 376-377).
A maar is a low-relief, broad volcanic crater formed by shallow explosive eruptions. The explosions are usually caused by the heating and boiling of groundwater when magma invades the groundwater table. Maars often fill with water to form a lake.
Photograph by C. Nye on 9 May 1994 Alaska Division of Geological and Geophysical Surveys
Aerial view toward N of Ukinrek Maars, Alaska; Lake Becharof at top of photo. Water partially fills the eastern maar and completely covers a lava dome that was erupted in the 100-m deep crater during a 10-day eruption in 1977. Maar is about 300 m in diameter.
Photograph by R. Russell on 6 April 1977 Alaska Department of Fish and Game
Eruption column generated by phreatic and magmatic explosions rises from the larger east maar.

Glossary of volcanic terms. - University of Wisconsin Oshkosh. . 2001.

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  • maar — maár s. n. Trimis de siveco, 10.08.2004. Sursa: Dicţionar ortografic  MAÁR s.n. (geol.) Depresiune rotundă, asemănătoare unui crater de dimensiuni relativ mici, mărginită de un val alcătuit din tufuri vulcanice sau din material care nu este de… …   Dicționar Român

  • Maar — 〈n. 11; Geol.〉 mit Wasser gefüllte, runde Bodenvertiefung vulkanischen Ursprungs [<vulgärlat. mara „stehendes Gewässer, See“ <lat. mare „Meer“] * * * I Maar   [wohl aus vulgärlateinisch mara »stehendes Gewässer«, »See«, von lateinisch mare… …   Universal-Lexikon

  • Maar — Sn Kratersee per. Wortschatz fach. (20. Jh.) Entlehnung. Entlehnt aus spl. mara f. See , das auf l. mare Meer (Meer) zurückgeht. Als Bestandteil von Namen schon früher bezeugt.    Ebenso nndl. maar, kratermeer, ne. maar, nfrz. maar, nisl. mar (… …   Etymologisches Wörterbuch der deutschen sprache

  • maar — ● maar nom masculin (allemand Maar, cratère) Cratère d explosion volcanique, généralement occupé par un lac …   Encyclopédie Universelle

  • maar — maȃr m DEFINICIJA geol. vulkanska udubina u tlu, većinom ispunjena vodom ETIMOLOGIJA njem. Maar ← nizoz …   Hrvatski jezični portal

  • Maar [1] — Maar, See, welcher in einem verloschenen Krater eines Vulkans entstanden ist …   Pierer's Universal-Lexikon

  • Maar [2] — Maar (Ülmener), kleiner Landsee im Regierungsbezirk Coblenz der preußischen Rheinprovinz …   Pierer's Universal-Lexikon

  • Maar — Maar, kesselförmige, oft mit Wasser gefüllte und von einem Schlackenkranze umgebene Einsenkung in vulkanischen Gegenden, meist kreisrund, z.B. in der Eifel …   Kleines Konversations-Lexikon

  • Maar — 〈n.; Gen.: (e)s, Pl.: e; Geogr.〉 mit Wasser gefüllte runde Bodenvertiefung vulkanischen Ursprungs [Etym.: <vulgärlat. mara »stehendes Gewässer, See« <lat. mare »Meer«] …   Lexikalische Deutsches Wörterbuch

  • Maar — (izg. mȃr), Dora (pravo ime Henriette Théodora Markovich) (1907 1997) DEFINICIJA francuska slikarica i fotografkinja hrv. porijekla; živjela s Picassom u Parizu 1936 1943, fotografski dokumentirala njegov rad na Guernici; Picasso ju je često… …   Hrvatski jezični portal

  • Maar — Maar, das; [e]s, e (Geografie kraterförmige Senke) …   Die deutsche Rechtschreibung

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