Volcanic crater

Craters on Mount Cameroon
The volcanic crater of a Tangkuban Parahu mount, Bandung, Indonesia

A volcanic crater is an approximately circular depression in the ground caused by volcanic activity.[1] It is typically a bowl-shaped feature within which occurs a vent or vents. During volcanic eruptions, molten magma and volcanic gases rise from an underground magma chamber, through a tube-shaped conduit, until they reach the crater's vent, from where the gases escape into the atmosphere and the magma is erupted as lava. A volcanic crater can be of large dimensions, and sometimes of great depth. During certain types of explosive eruptions, a volcano's magma chamber may empty enough for an area above it to subside, forming a type of larger depression known as a caldera.

Geomorphology

In most volcanoes, the crater is situated at the top of a mountain formed from the erupted volcanic deposits such as lava flows and tephra. Volcanoes that terminate in such a summit crater are usually of a conical form. Other volcanic craters may be found on the flanks of volcanoes, and these are commonly referred to as flank craters. Some volcanic craters may fill either fully or partially with rain and/or melted snow, forming a crater lake.

A crater may be breached during an eruption, either by explosions or by lava, or through later erosion. Breached craters have a much lower rim on one side.

Some volcanoes, such as maars, consist of a crater alone, with scarcely any mountain at all. These volcanic explosion craters are formed when magma rises through water-saturated rocks, which causes a phreatic eruption. Volcanic craters from phreatic eruptions often occur on plains away from other obvious volcanoes. Not all volcanoes form craters.

See also

  • Caldera – Cauldron-like volcanic feature formed by the emptying of a magma chamber

Footnotes

  1. ^ "Glossary of Terms: C". physicalgeography.net. Retrieved 2008-04-12.

External links

Other Languages
العربية: فوهة بركانية
azərbaycanca: Vulkan krateri
беларуская: Вулканічны кратар
Deutsch: Vulkankrater
eesti: Kraater
Esperanto: Vulkana kratero
euskara: Krater
한국어: 화구
Ido: Kratero
Bahasa Indonesia: Kepundan
íslenska: Eldgígur
עברית: לוע הר געש
Kreyòl ayisyen: Chemine
Кыргызча: Кратер
lietuvių: Krateris
македонски: Вулкански кратер
Bahasa Melayu: Kawah gunung berapi
Nederlands: Vulkaankrater
日本語: 火口
Plattdüütsch: Vulkankrater
português: Cratera vulcânica
română: Crater vulcanic
Runa Simi: Nina urqu luq'u
Simple English: Volcanic crater
slovenčina: Sopečný kráter
slovenščina: Vulkanski krater
српски / srpski: Вулкански кратер
srpskohrvatski / српскохрватски: Vulkanski krater
svenska: Vulkankrater
татарча/tatarça: Кратер
Tiếng Việt: Miệng núi lửa
中文: 火山口