Kilauea Activity Suggests New Eruption Possible

Kilauea volcano appears ready to flex some muscle again.

Scientists at the Hawaiian Volcano Observatory say the current activity inside the mountain is similar to what was observed nearly two years ago. And that resulted in an eruption at a new vent.

Kilauea, including its east rift zone, has seen an increase in both swelling and number of earthquakes for about the past month, HVO said in its latest Volcano Watch column issued today.

Geologists say there are basically three reasons the volcano inflates: either the amount of magma supplying the volcano has increased, the amount being erupted has decreased, or both are occurring.

They see a possible parallel to what began in late 2010 when there was an increase in tremor and inflation at the summit and the east rift zone. At the time there was also a rise in the level of lava in the vent in Halemaumau which had opened two years earlier.

Several months after that activity began in 2010, a new vent opened west of the Pu`u `O`o, between the cone and Napau Crater.

The Kamoamoa fissure eruption, which began on March 5, 2011, lasted 4½ days.

The level of lava in the lake in the southwest corner of Halemaumau has been rising again. Last week it hit a new high mark, coming to within 72 feet of the crater’s floor before dropping back down.

HVO’s scientists say if the current activity continues, the buildup in pressure could result in a new eruption. The only other alternatives are an increase of lava being erupted from Pu`u `O`o or an intrusion of magma underground somewhere else in the east rift.

HVO also postulates on where a new vent might open.

“Past patterns suggest that new activity will probably occur somewhere along the east rift zone between the summit and near Pu`u `O`o,” the column said.

The scientists note that many new vents have formed in the vicinity of Pu`u `O`o, which is currently feeding a lava flow that is slowly advancing toward the ocean across the coastal plain.

P`u `O`o was also where the current eruption began on Jan. 3, 1983. Since then it has become the most prolific – in terms of volume of lava – on the east rift zone in 500 years.

HVO’s scientists say they will continue to track the volcano’s activities, which includes the deployment of additional instrumentation.

“Perhaps the best lesson of the current inflation, seismicity, and lava level rise is that it pays to be vigilant,” the column said. “Kilauea is giving warning signs of a potential change in eruptive activity, allowing everyone to prepare for that eventuality.”