On Kilauea volcano's east rift zone on the big island of Hawaii, a lava lake perched in the Pu'u O'o cone grew higher and higher. It grew so high it began to spill over the walls of the cone. Then, suddenly, the bottom of the lake failed and lava began to erupt near the base of the cone.
HAWAI'I ISLAND, Hawaii — At 2:05 p.m., HST, this afternoon, the USGS Hawaiian Volcano Observatory (HVO) monitoring network detected the onset of rapid deflation of the Pu`u `Ō `ō crater floor. Soon thereafter, at 2:20 p.m., lava broke out at the base of the west flank of the Pu`u `Ō `ō cone.
According to Jim Kauahikaua, HVO’s Scientist-in-Charge, the breakout points are 0.7 km (0.4 mi) east of the eastern end of the Kamoamoa fissure that erupted earlier this year, in March 2011, or about half way between Pu`u `Ō `ō Crater and the eastern end of the Kamoamoa fissure.
“Interestingly, as the crater floor deflated , lava in the perched lake within Pu`u `Ō `ō Crater continued to circulate, just as it had over the past several weeks,” Kauahikaua noted, “but, by 3:15 p.m., the crater floor and lava lake began to collapse.”
HVO scientists at the eruption site reported a branched lava flow moving down Kīlauea’s south flank. The weaker northwest arm was pushing into kipuka and forest, while the higher volume, larger south arm had advanced at least 3 km (1.8 mi) downslope as of 3:50 p.m. The lava flow is entirely within Hawai‘i Volcanoes National Park, and poses no hazard to residents at this time.
Because the whole east rift system from Kilaeua caldera to Pu'u O'o cone was storing magma up to the high level the perched magma lake had reached in Pu'u O'o, a large amount of lava suddenly flowed across the volcanoes national park when the eruption broke loose.
More videos of the source areas of the flows after the croissant.