Geologists say the eruption on Kilauea’s lower East Rift Zone most likely will continue for months to years.
That’s a preliminary analysis contained in a report the U.S. Geological Survey’s Hawaiian Volcano Observatory recently submitted to Hawaii County Civil Defense.
The eruption, which started May 3 in Leilani Estates, has far outpaced other eruptions in the area in terms of volume in the past couple hundred years, and is producing an 8-mile-long lava channel to the ocean at Ahalanui. More than 700 homes have been destroyed.
Geologists say the sustained withdrawal of magma from Kilauea’s summit without appreciable ground deformation on the lower rift zone suggests the eruption remains stable.
“If the ongoing eruption maintains its current style of activity at a high eruption rate, then it may take months to a year or two to wind down,” the report says. “While this seems to be the most likely outcome, a pause in the eruption, followed by additional activity, cannot be ruled out, nor can an abrupt cessation or a transition to a steady, longer-lived activity at a lower effusion rate.”
The eruption has remained focused at fissure 8 within Leilani since late May and the chances of it moving to another site are becoming less likely, though still possible, the report says.
The fissure created a cinder cone more than 180 feet tall, but continues to erupt over a 200- to 260-foot-long segment and, if it becomes more concentrated, could create lava fountains nearly 1,000 feet tall and spread Pele’s hair and cinder over a wider area.
Gas emissions also remain much higher than recent years, with more than 30,000 metric tons per day being released. That’s more than four times the daily average for the summit prior to May 3.
“Fissure 8 is now the dominant producer of volcanic gas on the island of Hawaii and will remain so as long as current rates of eruption continue,” the report says.
The document looks at different hazards posed by the ongoing event, including the potential for other residential areas to be inundated.
For residents of Nanawale Estates and the Waa Waa area, the main risk appears to be a blockage in the lava channel, itself now 72 feet tall in places, which could divert the flow. That was seen near Kapoho Crater, when the flow moved toward Ahalanui and destroyed the “Warm Pond” and Kua o ka La Public Charter School.
The ocean entry there has spread toward Isaac Hale Beach Park and Pohoiki boat ramp, but remained 0.3 miles from the ramp as of Friday afternoon.
Collapse events at Kilauea’s summit have damaged Highway 11 at Hawaii Volcanoes National Park. The state Department of Transportation is reducing the speed limit there to 25 miles per hour between mile markers 28 and 30.
To view HVO’s report, visit https://tinyurl.com/LERZeruption.
Email Tom Callis at tcallis@hawaiitribune-herald.com.