A jet of
lava
sprayed into the air by the rapid formation and expansion of gas
bubbles in the molten rock is called a
lava fountain.
Lava
fountains typically range from about 10 to 100 m in height, but
occasionally reach more than 500 m. Lava fountains erupt from
isolated
vents, along
fissures, within active lava lakes, and from a
lava tube
when water gains access to the tube in a confined space (see type
of explosive activity where lava enters the sea, from the USGS
Hawaiian Volcano Observatory).