A
rift zone is a feature of some
volcanoes, especially
shield volcanoes, in which a linear series of
fissures in the volcanic edifice allows
lava to be erupted from the volcano's flank instead of from its summit. For example, in the currently ongoing eruption of
Kilauea in
Hawaii, lava is emitted continuously from the
Puu Oo vent located in Kilauea's East Rift Zone roughly 15 km east of Kilauea Crater. Rift zones tend to extend for tens of kilometers radially outward from the volcanic summit. The accumulated lava of repeated eruptions from rift zones causes these volcanoes to have an elongated shape. Perhaps the best example of this is
Mauna Loa, which in
Hawaiian means "long mountain".