Volcanic fissures and lava flows - what's the difference?

2018-05-08 2

PUNA, HAWAII — Hawaii's Big Island continues to be plagued by volcanic eruptions, which have destroyed several homes and forced roughly 2,000 people to evacuate.

Reuters reports that lava flows and fissures have caused a large part of the damage, though it's important to make a distinction between the two in order to better understand the situation.

According to the U.S. Geological Survey, lava flows are streams of hot molten rock that pour out onto the earth during an effusive eruption.

Lava flows come in different sizes and speeds depending on the viscosity of the lava. Its path is possible to predict since flows are confined by topography.

Volcanic fissures meanwhile, are linear vents usually a few meters wide and several kilometers long through which lava spews out.

Scientists may know the general direction of magma flow underground, but it's impossible to predict when and where fissures will appear.

Seismic activity and cracks on the ground may indicate that a fissure will soon appear, but the unpredictability of this force of nature definitely makes the situation in Hawaii even more dangerous.