Kilauea’s current eruption started on Jan. 3, with a series of fissures several miles east of the caldera on what’s called the East Rift Zone. The eruption eventually centered on the Pu‘u ‘O‘o vent.
The eruption moved downslope from the Kilauea summit. For more than five years, the Kupaianaha tube system sent flows to the coast. During this period, the lava wiped out the communities of Kalapana, Royal Gardens and Kapa‘ahu, all effectively destroyed by 1990. Kalapana was buried under 50 to 80 feet of lava.
Starting in November 1991, fissures erupted between Kupaianaha and Pu‘u O‘o, and within months, Kupaianaha stopped erupting. Activity moved back to Pu‘u O‘o by early 1992, the start of a series of flank vents that were active over the next 15 years. As at Kupaianaha, the style of the eruption was a nearly continuous effusion of lava.
In January, lava production at the Pu‘u O‘o site dropped, the crater floor collapsed, and one side of the cone wall fell down. Meanwhile, fissures opened and erupted upslope near Napau Crater. But this activity lasted only about a day, and for three weeks afterward, there was no fresh lava on Kilauea’s flanks. Then Pu‘u O‘o started up again.
An earthquake swarm and broad summit deflation were believed to accompany a magma movement into the upper East Rift Zone. The diverting of magma into underground fractures is believed responsible for an 11-day break in the eruption, the longest pause in activity since the hiatus after the 1997 cone collapse.
On Mother’s Day, a new flank vent opened on the west side of Pu‘u ‘O‘o, feeding flows that sparked the largest forest fire in Hawaii Volcanoes National Park in 15 years, consuming 880 acres. The Mother’s Day flow reached the ocean near the end of Chain of Craters Road in July, and for the next year and a half, lava entered the ocean nearly continously at several locations on the western side of the flow field.
In January, lava flowed out of the Pu‘u ‘O‘o crater for the first time since 1998. In March, there was a major breakout on the southwest side of Pu‘u ‘O‘o, dubbed the Prince Kuhio Kalaniana‘ole flows, which eventually became the dominant lava tube and remained active for three years, sending lava to the ocean at several locations in the national park.
Tube-fed lava reached the ocean at intermittent entries from March 2008 to February 2011. In mid-2010 and early 2011, lava flows reached the Kalapana Gardens subdivision, destroying three homes.
In March, the last holdout of the lava-besieged Royal Gardens subdivision was forced out by a fresh lava flow. His home was destroyed. Overall, while the Pu‘u ‘O‘o eruption remains active, it appears the amount of lava flowing on the coastal plain declined over the last year. That does not necessarily indicate the eruption will cease anytime soon.