This is my transcript of the July 2, 2018 11am USGS press briefing, which covered lava-created thunderstorms, whirlwinds, and rain; laze-induced lightning; and lava boats. Additionally, Mike Zoellner mentioned findings of a sonar expedition to measure the lava extending on the ocean floor.
Soundfile is archived here. BigIslandVideoNews has also posted most of it, overlaid with recent video footage:
Leslie Gordon, USGS Public Affairs
Jessica Ferracane, Hawaii Volcanoes Nat’l Park Public Affairs
Robert Ballard, NWS
Mike Zoeller, HVO & Center for the Study of Active Volcanoes, UHI
Brian Shiro, seismologist, USGS/HVO
Transcript note: I omit salutations/pleasantries, jumping straight to news and information. Also I usually summarize questions to provide just enough context for USGS responses.
Fissure 8 just keeps on going, as if it’s settling in for a Pu’u O’o eruption rather than a 1955/1960 eruption. Once again, there’s minor overflows upriver that don’t go anywhere. The ocean entry is mostly via the channel on the south side of the lava delta, but there’s also trickles along a kilometer-wide stretch of shore. Fissure 22 showed incandescence but no lava during the USGS morning overflight.
The USGS was skimpy on images today but gave us a treat: a timelapse of what they call “lava boats.”
Here’s their explanation: “Geologists captured this time-lapse video of the perched lava channel issuing from fissure 8 on Kīlauea’s lower East Rift Zone. Rafts of accreted lava move down stream and look like boats moving down a river. These are termed lava balls or lava boats and form when portions of the fissure 8 cone or levees break away and are rafted down stream. As they move along in the channel, additional lava can cool to their surface to form accretionary lava balls.”
After lots of minor earthquakes and rockfalls that sent up small plumes of dust, the daily summit “collapse explosion” occurred at 4:34pm. It sent up a 2000-foot plume, once again equivalent to 5.3 earthquake. Again, I couldn’t resist a video capture:
The runup to today’s explosion was impressive. There was one cascade of dust and rubble all the way around the walls that I would’ve taken for the day’s explosive event, except that there was no camera shake beforehand. Doubtless it was one of these:
There’s not much news today, so let’s hitch a ride with the Hawaii County Fire Department and follow the lava river to the ocean. But first….
More on Lava Boats
I’d asked about the “lava boats” before that video was posted: “What’s forming those so-called “lava bergs”? Are they chunks off the sides of the levees? Do they indicate erosion/undermining of lava channel’s banks analogous to meanders of an H20 river, with risk of wearing through?”
@USGSVolcanoes offered some additional info in response: “They are chunks of the sides of levees as well as bits of the cone. As lava moves by them in the channel, they can be coated, dislodged, etc. Different than water – lava cools against cooler surfaces (channel sides) & we’ve started to see portions roofing over (forming tubes).” And when someone else asked if the whole 8 mile channel might become a lava tube: “It’s a possibility, but not necessarily guaranteed. It’s easier in places where the channel is already narrow.”
Which doesn’t answer my question about erosion/meanders, but looking back, they answered another question about braided lava channels on June 11 with this paper, which emphasizes that viscosity is a major factor in lava flows, whereas in H2O it’s particles in water.
Someone else’s Q on “lava boats”: ” Are these what’s floating beyond the ocean entry? USGS: That’s a different process. The chunks floating beyond the ocean entry are bits of very bubble-rich lava-rock. When lava enters the sea there is sometimes an explosive process that expels rocks – the heat of the rock combined with the amount of bubbles causes these pieces to float for a while. Eventually, they cool, fill with water, and sink.
Awkward place to stick this, but so I don’t forget: this week’s HVO “Volcano Watch” newsletter focused on “Mauna Loa Back to Normal.“
More USGS on Social Media
Q: What will happen if the summit collapse continues? USGS: There are several options: It could enlarge #Halemaumau to a point and then the explosive activity could stop, or it could enlarge the crater and the explosions could change character.
Aha! It turns out the USGS posted photos today only on Facebook. Someday when things calm down, they need to comb their social media channels and make sure they’ve archived everything on the HVO website and/or USGS media library.
If the USGS is too busy to post photos, the Hawai’i County Fire Department takes up the slack. (Unlike Facebook, Flickr is Google-able). Today Civil Defense shared their latest photo album, and once again I’m impressed by the definition of the camera they’re using compared to everybody else.
A small sample:
Looking southeast towards the “Y” junction at Pokoihi Rd, Kapoho Rd and 132 (Google Map) with Puna Geothermal Ventures in the background on the left:
Left and right, as different as night and day:
A disagreeable neighbor:
Looking towards the new lava delta:
Past the Lava Rooster house (near that mast):
Past the Cinder Pit:
Around Kapoho Crater (and former Green Lake):
To the sea. (Note upwelling.)
Effects extend offshore…
So far, so lucky. (Note the 1960 lava flow with roads on it.)
(warning: helicopter noise)
Sorry, got carried away. But there’s another 98 photos/videos in that album, including video all along the route and detailed views of houses, farms, even a dock.
A lot of the landscape resembles a hell-like atmosphere. The stench of sulfur, the rumble of the lava boil, and death as far as the eye can see. It's both magical and extraordinarily sad. #KilaueaEruptionpic.twitter.com/XWzQcbDX4u