Photograph by E.W. Wolfe on 16 December
1986
Lava lake
Lava lakes are large volumes of molten lava, usually basaltic,
contained in a vent, crater, or broad depression. Scientists
use the term to describe both lava lakes that are molten and
those that are partly or completely solidified. Lava lakes can form
(1) from one or more vents in a crater that erupts enough lava to
partially fill the crater; (2) when lava pours into a crater
or broad depression and partially fills the crater; and (3)
atop a new vent that erupts lava continuously for a period
of several weeks or more and slowly builds a crater higher
and higher above the surrounding ground.
Image shows an aerial view of a lava lake atop the Kupaianaha vent on the
east rift zone of Kilauea Volcano, Hawai`i. The fume rising
from the end of the narrow part of the lava lake marks the
beginning of a lava tube.
Did you know?
- Active lava lakes typically consist of a partially solidified shiny gray
crust because its surface is constantly cooled by the atmosphere.
The crust is seldom more than 5-30 cm thick, or more than a few
minutes or hours old, because the crust continually circulates, breaks,
and sinks into the moving molten lava below. The pattern of movement
on the surface of lava lakes is often compared to the type of
large-scale movement that occurs between the huge plates
that make up the Earth's crust, including subduction, spreading, and
strike-slip movement.
- Lava lakes occur at relatively few volcanoes in the world. For
example, since 1980, lava lakes have formed at Kilauea
Volcano in Hawai`i, Mount Erebus in Antarctica (involving rare
phonolitic lava), Erta' Ale in Ethiopia and Nyiragongo in Zaire.