A volcanic plateau is a plateau produced by volcanism. There are two main types: lava plateaus and pyroclastic plateaus.
Lava plateau
Lava plateaus are formed by highly fluid
lava during numerous successive eruptions through numerous vents without violent explosions (quiet eruptions). These eruptions are quiet because of the low viscosity of the lava and the small amount of trapped gases. The resulting sheet lava flows may be extruded from linear
fissure vent or
or gigantic volcanic eruptions through multiple vents characteristic of the prehistoric era which produced giant
. Multiple successive and extensive
lava flows cover the original landscape to eventually form a plateau, which may contain
,
,
shield volcanoes and other
volcanic landforms. In some cases, a lava plateau may be part of a single volcano. An example is the massive
Level Mountain shield volcano in northern
British Columbia,
Canada, which covers an area of and a volume of .
Charles A. Wood (1990). 052143811X, Cambridge University Press. 052143811X
Perhaps the most extensive of all the subaerial basaltic plateaus existed during the Paleogene[ Brittle tectonism in relation to the Palaeogene evolution of the Thulean/NE Atlantic domain: a study in Ulster Retrieved on 2007-11-10] and possibly extended over of the northern Atlantic Ocean region. This region, known as the Thulean Plateau, is generally believed to have been broken up by the foundering of the Earth's crust to form the present oceanic basin.
Earth features numerous subaerial and submarine volcanic plateaus, such as the Columbia River Plateau (subaerial) and the vast Ontong Java Plateau (submarine).
Pyroclastic plateau
Pyroclastic plateaus are produced by massive
. They are underlain by
:
,
tephra,
cemented into
,
mafic or
felsic. Pyroclastic plateaus are also called
ignimbrite plateaus.
Examples include the Shirasu-Daichi, which makes up almost all of southern Kyushu, Japan,
See also
-
Cézallier massif – Volcanic plateau from France
