July 23: Pohoiki Going Tonight (I Think)

July 23, 2018. View of lava channel from F8 where it bends to south and heads for ocean (laze plume in background). USGS: “The fissure 8 channel continues to carry lava toward the coast on the west side of Kapoho Crater (vegetated cone, far left). Northwest of this cone, overflows (lower left) of the channel occurred overnight, but lava was confined to the existing flow field and did not threaten any homes or structures.” (Full-sized)
Today’s Eruption Summary

The USGS has updated the energy release for yesterday evening’s summit collapse to  M5.5. (For more info: “Why Do Earthquake Magnitudes Sometimes Change?” from a 2016 issue of Volcano Watch by HVO.)

Fissure 8 exhibited surge behavior afterwards. Overnight, drone crews observed minor overflows just northwest of Kapoho Cone, most of which were confined to the existing flow field and/or stopped before traveling far enough to threaten structures.

July 23, 2018. USGS: “Lava continued to enter the sea near Ahalanui during HVO’s early morning helicopter overflight of Kīlauea’s lower East Rift Zone (view to northeast). The southern margin of the flow was still about [a quarter mile] from the boat ramp at Isaac Hale Park this morning. The jetty along the launch ramp is visible near the center of the photo.” (Full-sized)
The main ocean entry and southern margin of the flow haven’t moved much in the past few days. However, USGS reports “a new lobe has started from the southern lobe and is active along its southwestern margin, slowly heading towards the ocean.” Today’s 1 pm map clarifies the new lobe’s location:

July 23, 2018, 1 pm USGS map of LERZ lava flow field. Note small overflow by Fissure 8 as well as upstream of Kapoho bend on the north side of the braided channels. (Full-sized)

Ikaika Marzo, a lava tour boat operator who stays a sensible distance from shore, reportedly saw lava is in Isaac Hale Park, within 50 m of Pohoiki boat ramp at 7:15 this evening.

No summit collapse today, unless the pattern changes; the next one ought to occur tomorrow morning.

Here’s highlights of the USGS Media Conference Call from this afternoon:

Full audio file archived here.

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