A weekly feature provided by scientists at the Hawaiian Volcano Observatory.
January 2, 2014
Kīlauea’s Puʻu ʻŌʻō eruption still going after 31 years
On January 3, 2014, Kīlauea's Puʻu ʻŌʻō eruption surpasses 31 years of activity. The ongoing eruption has evolved tremendously during its complex history. While it is impossible to recount in detail every episode of this long-lived East Rift Zone eruption in a Volcano Watch article, we mark its anniversary with a recap of highlights through the years.
It came as no surprise to USGS Hawaiian Volcano Observatory scientists when a new fissure opened along Kīlauea's East Rift Zone on January 3, 1983. This area had hosted a series of intrusions and short-lived eruptions from the early 1960s through the early 1980s. But after towering lava fountains began erupting from a single vent in June 1983, it was recognized that this eruption was different.
The lava fountains were episodic, with each eruption lasting about a day and occurring about every 3 weeks, and progressively built the pyroclastic cone now called Puʻu ʻŌʻō. In addition, the lava fountains spawned fast-moving ʻaʻā flows, some of which destroyed houses in the sparsely populated Royal Gardens subdivision.
In July 1986, the eruption shifted 3 kilometers (2 miles) to the east and changed style. Rather than episodic fountains, lava flows erupted nearly continuously, forming a low, broad lava shield that was later named Kupaianaha.
Pāhoehoe flows erupted from Kupaianaha crept slowly downslope, building lava tubes as they advanced. These tubes insulated the molten lava, which enabled flows to travel farther and reach the more populous coastline. Over the following years, houses were buried on both sides of the widening flow field and the village of Kalapana was partially destroyed in 1990.
The Kupaianaha vent died in February 1992, when the eruption shifted to new vents on the southwest flank of the Puʻu ʻŌʻō cone. New lava tubes were constructed as the lava again advanced downslopethis time mostly within Hawaiʻi Volcanoes National Park. A lava shield, pockmarked with collapse pits, slowly buried the southwest flank of Puʻu ʻŌʻō.
Eruption from Puʻu ʻŌʻō's southwest flank vents predominated for the next 15 years, finally coming to an end in June 2007, when the Father's Day fissure eruption occurred west of Puʻu ʻŌʻō. This change led to the establishment of a new vent between Puʻu ʻŌʻō and Kupaianaha that sent flows back to Kīlauea's southeast coast, where they destroyed several more homes in Royal Gardens and Kalapana Gardens subdivisions. Kīlauea's ongoing summit eruption also began during this period (in March 2008).
The next big change came in early March 2011, when the 4-day-long Kamoamoa fissure eruption west of Puʻu ʻŌʻō was followed by the cessation of eruptive activity along the East Rift Zone. But the eruption resumed in late March, and lava slowly filled the Puʻu ʻŌʻō crater over the following months. Then, in September 2011, the "Peace Day" vent opened high on the east flank of the Puʻu ʻŌʻō cone and sent lava flows back to Kīlauea's southeastern coast for the next two years.
In January 2013, the Peace Day flow, which was relatively weak compared to much of Puʻu ʻŌʻō's past eruptive activity, was joined by a flow fed directly from a spatter cone at the northeast edge of the Puʻu ʻŌʻō crater floor. But this new flowthe Kahaualeʻa flowadvanced toward the northeast rather than to the southeast. With the establishment of the Kahaualeʻa flow, the Peace Day flow began to wane and, in November 2013, the Peace Day flow died.
The slow transition of activity from the Peace Day flow to the Kahaualeʻa flow marks a dramatic change in the risk posed by the eruption. Unless there is a significant change at Puʻu ʻŌʻō, the Kahaualeʻa flow poses no imminent threat to infrastructure, but will likely continue advancing toward the northeast, burning forest as it does. It could eventually reach communities far downslope, but fortunately, the East Rift Zone eruptive output remains weak. At its current pace, the Kahaualeʻa flow would take more than a year to reach populated areas.
Over the past 31 years, just over 4 cubic kilometers (about 1 cubic mile) of lava have been erupted, covering 128 square kilometers (49 square miles) of land and destroying 214 structures. Only time will tell how the eruption evolves in the New Year. As the saying goes, "May you live in interesting times."
Kīlauea Activity UpdateA lava lake within Halemaʻumaʻu produced nighttime glow that was visible via HVO's Webcam during the past week. Summit tiltmeters recorded minor variations, but overall the tilt level was relatively steady. The lava lake level rose slowly and was about 45 m (148 ft) below the rim of the Overlook crater on Thursday, January 2.
On Kīlauea's East Rift Zone, the Kahaualeʻa 2 flow continued to advance very slowly into the forest northeast of Puʻu ʻŌʻō. The active front of the flow was about 6.3 km (3.9 miles) northeast of Puʻu ʻŌʻō when mapped on December 26.
There were no earthquakes reported felt on the Island of Hawaiʻi in the past week.
Visit our Web site (hvo.wr.usgs.gov) for detailed Kīlauea and Mauna Loa activity updates, recent volcano photos, recent earthquakes, and more; call (808) 967-8862 for a Kīlauea activity summary; email questions to askHVO@usgs.gov.