EGEST
(ee-JEST)
To
discharge or eliminate from the body
Common
clues: Discharge;
Excrete; Spew out; Cast out; Throw out; Void; Perspire
Crossword
puzzle frequency:
once a year
Video:
Hawaiian
Volcano Still Spews Hot Lava
The
most common perception of a volcano is of a conical mountain,
spewing lava and poisonous gases from a crater at its summit.
This describes just one of many types of volcano, and the
features of volcanoes are much more complicated. The structure
and behavior of volcanoes depends on a number of factors. Some
volcanoes have rugged peaks formed by lava domes rather than a
summit crater, whereas others present landscape features such as
massive plateaus. Vents that issue volcanic material (lava, which
is what magma is called once it has escaped to the surface, and
ash) and gases (mainly steam and magmatic gases) can be located
anywhere on the landform. Many of these vents give rise to
smaller cones such as Puʻu ʻŌʻō on a
flank of Hawaii's Kīlauea.
A
view taken from the International Space Station of the Sarychev
Volcano on the Kuril Islands in an early stage of eruption on
June 12, 2009.
Other
types of volcano include cryovolcanoes (or ice volcanoes),
particularly on some moons of Jupiter, Saturn and Neptune; and
mud volcanoes, which are formations often not associated with
known magmatic activity. Active mud volcanoes tend to involve
temperatures much lower than those of igneous volcanoes, except
when a mud volcano is actually a vent of an igneous volcano.
This
article is licensed under the GNU
Free Documentation License.
It uses material from the Wikipedia
article "Volcano".
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