VOLCANO UPDATE: Lava Tube Collapses

On July 21, 2016, a Paradise Helicopter fly-over revealed a “huge pali collapse.”

Thursday morning, Kīlauea remained active on and above the coastal plain, widening and overplating the flow field, reported Paradise Helicopters.

But the distal tip just over a half-mile from the ocean is still stalled out for the time being.

Lava rolled over the Pulama Pali three weeks ago, mostly between Hawai‘i Volcanoes National Park and the abandoned Royal Gardens subdivision. This new flow, dubbed “61G” is now over five miles long.

Nearly the entire last mile of the distal tip was inactive this morning, with only two sizable outbreaks observed above… one about one-third miles long on the pali, and the second, a large pahoehoe flow on the coastal plain, about a half mile from the first, Paradise reported.

But of greatest interest today was a huge collapsed lava tube near the remaining trees in Royal Gardens, most of the way down the Pali. Somewhere in the neighborhood of 60 feet or more in diameter, the hole revealed layers of hot molten rock and two rivers snaking slowly beneath several shelves.

Hawaiian Helicopters was unable to locate any skylights above the Pali, but could only get about halfway to the vent due to the inclement weather.

How soon the flow could reach the ocean is a bit of a mystery now, as activity seems to have slowed considerably, and the flow front is not moving.

USGS Activity Summary: Eruptive activity continues at Kīlauea Volcano’s summit and East Rift Zone. The 61G lava flow extending southeast of Puʻu ʻŌʻō towards the ocean remains active but poses no threat to nearby communities. As of yesterday, the flow tip was stalled about ~850 m (0.5 miles) from the ocean. The lava lake at Halemaʻumaʻu Crater continues to circulate and intermittently spatter. Seismicity and deformation rates throughout the volcano remain at background levels.

Summit Observations: The lava lake within the Halemaʻumaʻu Overlook crater remains active. The depth to the lake was measured at 23 m (75 ft) below the crater rim, on the evening of, July 20, 2016. Tiltmeters at Kīlauea’s summit recorded inflationary tilt. Seismicity is within normal, background rates with tremor fluctuations associated with lava lake spattering. The summit sulfur dioxide emission rate ranged from 3,700 to 7,300 metric tons/day.

Puʻu ʻŌʻō Observations: Webcam images over the past 24 hours show persistent glow at long-term sources within the crater. There were no significant changes in seismicity or tilt over the past 24 hours. The sulfur dioxide emission rate from all East Rift Zone vents on July 15 was about 270 metric tons/day.

Lava Flow Observations: The 61G lava flow extending southeast of Puʻu ʻŌʻō towards the coastal plain on Kīlauea’s south flank remains active. On Wednesday, the flow tip was inactive but breakouts were active within a few hundred meters (yards) upslope. Yesterday, a field crew visited the flow field and noted the flow was approximately 720 m (.4 miles) from the coastal emergency road and 850 m (0.5 miles) from the ocean. Areas of incandescence remain visible in overnight webcam views of the active lava flow field, marking lava tube skylights and areas of active lava on the pali and along the flow as it extends towards the coast.