August 19: The Lull Continues

This Week’s Eruption Activity

Negligible. There’s a few residual bits of lava oozing into the ocean at Ahalanui. Otherwise, there’s not much going on at the summit or LERZ.

[In case Tweet above isn’t showing, here’s the 3D Fissure 8 video on HVO website.]

USGS: “This thermal map shows the fissure system and lava flows as of 6 am on Wednesday, August 15 [2018]. Residual lava in the Fissure 8 flow continues to drain, feeding numerous small ocean entries. In the Fissure 8 cone there was a single, small lava pond.” (Full-sized)
On Friday August 19, HVO lowered ground alert levels, just as they lowered aviation alert levels after the ash explosions stopped. Here’s the official notice:

In light of the reduced eruptive activity at Kīlauea Volcano over the last several days, HVO is lowering the Alert Level for ground based hazards from WARNING to WATCH. This change indicates that the hazards posed by crater collapse events (at the Kīlauea summit) and lava flows (Lower East Rift Zone; LERZ) are diminished. However, the change does not mean with absolute certainty that the LERZ eruption or summit collapses are over. It remains possible that eruption and collapse activity could resume.


Remarks: Background and Prognosis

Kīlauea Volcano has remained quiet for well over a week now, with no collapse events at the summit since August 2. Except for a small, crusted-over pond of lava deep inside the fissure 8 cone and a few scattered ocean entries, lava ceased flowing in the LERZ channel on August 6. Sulfur dioxide (SO2) emissions rates at the summit and LERZ are also drastically reduced (the combined rate is lower than at any time since late 2007).

It remains too soon to tell if this diminished activity represents a temporary lull or the end of the LERZ lava flows and/or summit collapses. In 1955, similar pauses of 5 and 16 days occurred during an 88-day-long LERZ eruption. During the Mauna Ulu eruption (1969-1974), a 3.5 month pause occurred in late 1971.

HVO will continue to record detailed visual observations and scrutinize incoming seismic, deformation, and gas data, looking for evidence of significant movement of magma or pressurization as would be expected if the system was building toward renewed activity.

Also on Friday, the National Park Service issued a media release and gave select local media a guided tour of the summit. Lots of info, and worth seeing:

This Week’s USGS Photos From Summit to Sea

Continue reading August 19: The Lull Continues