Kilauea summit’s lava lake is rising.
The summit and the Puu Oo Vent are puffing up.
Earthquakes are occurring at a rate of five to 15 a day versus the one to two a week average.
It all adds up to a possible explosive eruption of Kilauea Volcano.
"It’s kind of tough to read too much into it, but all of it together — inflation at the summit and Puu Oo, the rise in the lava lake and the earthquakes" — indicates a possible eruptive event, said Jim Kauahikaua, scientist in charge at the U.S. Geological Survey’s Hawaiian Volcano Observatory.
On Friday morning the lava lake within Halemaumau Crater rose to its highest level, about 125 feet beneath the crater floor, its highest level since an explosive eruption on March 19, 2008.
The observatory’s webcams also indicated the lake rose even higher before sinking Friday afternoon.
Visitors to the Jaggar Museum overlook might get a rare view of the lake if it rises within 65 feet of the crater floor.
Magma is pressurizing beneath the surface, which causes the inflation, as it did before the March 2011 eruptive event, Kauahikaua said. "We may be looking at something similar."
In March 2011 visitors came in droves to watch the fireworks at Kilauea, with red molten rock shooting up as high as 80 feet into the air. The volcano was pumping out lava at the rate of 2.5 million cubic meters of lava a day at the Kamoamoa Fissure, five times the amount previously coming out of the east rift zone.
Scientists at the observatory reported hearing echoing booms and popping and cracking sounds at the summit. Fresh spatter bits and Pele’s hair spewed from the vent in the gas plume. The sulfur dioxide emission rate was measured Thursday at 700 metric tons a day. The vent has been active since a small explosive event on March 19, 2008.
Meanwhile at the middle east rift zone vents, surface flows of lava continued to accumulate near the base of the Pulama Pali inside the abandoned Royal Gardens subdivision. One branch is heading seaward and remains a mile from the ocean.
At Puu Oo crater the lava lake in the northeastern pit on the crater floor briefly overflowed the northern rim four times between Thursday afternoon and early Friday morning. The south pit also saw some brief lava flows, and a small spatter cone had some action Thursday night.
Janet Babb, geologist and spokeswoman for the Hawaiian Volcano Observatory, said last week that one possible outcome of the recent activity is an outpouring of lava on the floor of Halemaumau Crater.
Another is that the increased pressure might overcome an apparent constriction in the volcanic plumbing system, and an outbreak could occur between the summit and Puu Oo, similar to the March 2011 Kamoamoa fissure eruption.
Babb said the summit vent has been slowly and fitfully rising for the past several months.
On Oct. 5 "lava reached a level that covered the previous high-lava ‘bathtub’ ring within the summit vent."
The rise in lava level in the vent is not likely due to an increase in magma supply from depth since no increase in carbon dioxide emissions has been detected, she said.
Another explanation for the uplift and expansion could be "a backup of magma by a constriction in the volcanic plumbing system between the summit magma reservoir and the Puu Oo vent on Kilauea’s east rift zone," Babb said.
The Hawaii Volcanoes National Park says visitors should gather at park overlooks after dark "to view the dramatic glow that lava beneath the surface casts upon clouds and the plume of volcanic gas."
