This lava flow inched towards Pahoa, Hawaii, but stalled. The risks for breakouts remain. Photo courtesy of Flickr/Hawaii National Guard.
By Julio Avila
Geologists cannot predict volcanic lava flows and do not know in which direction lava will flow after an eruption, according to a New York Times article published on Mar. 23 2015.
The researcher quoted for the article said this in regards to a lava flow from the Kilauea volcano in Hawaii that erupted since last June. The lava moved at a slow and steady pace where the flow was getting close to a town, Pahoa.
“We can predict things over long timescales,” Timothy Glotch, a geosciences professor at Stony Brook said. “On very short timescales, there’s so many factors in play that you can’t make precise predictions where it’s going to go.”
Predicting where lava will flow is dependent on a few factors. Some factors include topography and lava viscosity, the fluidity of it. Kilauea is a shield volcano where the lava consists of low silica content and is mafic with a low viscosity.
Satellites limit researchers’ abilities in that it can show where lava is at. As for the flow, if lava flows through a channel, it may gain speed. Lava eventually hardens on the surface, but can travel underneath the solidified lava. At random points, small lava breaks can penetrate through the solid crust and flow as toes, which are streams resembling actual toes and are slow.
“On any given day, lava can go from one place underground to another place,” Glotch said. “You might have another breakout you weren’t necessarily expecting.”
Kilauea first erupted in 1983, but has since had eruptions coming out of side vents. Lava escapes from vents around the caldera and can make for unexpected breakouts. This was the case for the June 27 2014 eruption that erupted around the Pu’u O’o crater.
Glotch spent time in Hawaii with the Hawaii Volcano Observatory studying volcanic activity. The HVO is also tracking Kilauea’s activity and providing updated information regarding locations of outbreaks along the flow. He said “they literally have a guy” who uses a handheld GPS to “walk around the perimeter of an active flow” to log updated extensions. This is made possible to the lava’s slow movement.
As for Pahoa, the lava flow became inactive that on Mar. 25, the HVO downgraded the threat level from a warning to watch. It also anticipated that “it will be at least months before lava could reach to within one mile or one week of homes or infrastructure.” As of the last seven days, the HVO’s hazard summary said breakouts “have advanced into Pāhoa and may threaten residential areas depending on their level of activity and advance rate.”