HILO >> Geologists at the Hawaiian Volcano Observatory are studying lava samples that might help fine-tune projections if Kilauea sends another 2,000-degree river of molten rock toward homes in lower Puna.
The lava flow saw its 1-year anniversary yesterday but hasn’t threatened populated areas since March, reported the Hawaii Tribune-Herald reported.
Geologist Frank Trusdell is nevertheless analyzing thousands of slides and counting crystals one by one.
"We got all the samples, sent them in for chemical analysis, and now we’re doing the nitty-gritty science," he said.
He wants to find out whether the lava flow changed in temperature or chemistry as it advanced down the slope. Certain changes could have increased the lava’s viscosity and made it more sluggish, which could explain why the flow has stopped about 14 miles from the vent, just before reaching the town.
"There’s not an invisible wall there that kept the flows from advancing downslope," cautioned Steve Brantley, the deputy scientist-in-charge at the volcano observatory.
The June 2014 eruption is the first time lava from the volcano’s Puu Oo vent stretched more than a few miles without being stopped by the ocean.
Researchers couldn’t say at the time how far the lava would go. Understanding changes in the flow as it advances could not only explain why the lava stopped short of Puna but also help scientists predict the impact of future eruptions.
"We could sample in real time and look at the crystallinity and make some judgments of how viscous is this lava, which would then provide some information as to how far the lava goes," Trusdell said.
"It’s still premature for us to actually go there," he added.
Factors that determine how a lava flow behaves include temperature, gas content, eruption output, leaks in the lava tube and alterations the lava makes to the landscape.
Whether the flow from the Puu Oo vent will eventually continue is unclear, and the geologists say there are multiple paths the lava could follow if starts flowing again.
For now, they said, it’s a matter of waiting to see what happens.
"These flows can be active in this area potentially for years," said volcano observatory geologist Tim Orr. "We don’t know."
"Nothing is imminent right now for sure."