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
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).