Photograph by R.W. Decker on March 25, 1984.

Lava erupts from a fissure high on the northeast rift zone of Mauna Loa (about 3400 m) on the morning of March 25, 1984. Fountains are 10 to 50 m high along the fissure, and lava output is estimated at 1-2 million m³/hour. This fissure fed a narrow `a`a lava flow that moved only about 5 km downslope before new vents became active farther downrift (see 1984 eruption narrative).