Tag: overflows

August 2: Word of the Day – ‘Tombolo’

August 2, 2018. USGS: “During this morning’s overflight, HVO geologists used a telephoto lens to capture this image of the fissure 8 cone. Activity within the vent was low, with small bubble bursts in the eastern part of the vent and low lava fountains on the western side. The fountains occasionally threw spatter onto the west rim of the cone (right).” (Full-sized)
Today’s Eruption Summary

The eruption continues as usual, although lava levels “in the more distant portions of the channel system” are down somewhat. Nevertheless, an afternoon surge after today’s summit collapse caused an overflow and brushfire in an undeveloped area north of the channel, according to Civil Defense.

Today’s summit collapse came at 11:55 am HST, energy equivalent of an M 5.4. Once again there was a cluster of high M3 foreshocks in the ten minutes or so beforehand, so that there was already some suspended dust from rockfalls.

Northeast Rim livestream cam was stuttering today, but still dramatic.

Also note that HVO’s Fissure 8 webcam was damaged by a brushfire Tuesday and ceased working. In fact, right now it’s stuck on the last photo it took.

While checking on the main webcams page, I caught a lovely time of the evening up at the summit. From the ones that are working:

Former Overlook Vent cam, now pointed at a sheer cliff above where it used to be. (Full-sized)
HVO Panorama cam. All of these from about 6:40 pm HST. (Full-sized)
Halema’uma’u wide angle webcam. (Full-sized)

And speaking of photos, I took a night off, and come back to find HVO posted a ton of good photos! Which I shall mirror here so they’re easier to find after they’ve “fallen off” that Photo & Chronology page.

Most importantly, a new frame from the Cosmo-Skymed satellite radar animation:

Aug 1, 2018. USGS: “This animated GIF shows a sequence of radar amplitude images that were acquired by the Agenzia Spaziale Italiana CosmoSkyMed satellite system. The images illustrate changes to the caldera area of Kīlauea Volcano that occurred between May 5 and August 1 at about 6:00 a.m. HST.” (Full-sized

Accompanying text with this animation: “Over time, expansion of the summit eruptive vent within Halema‘uma‘u crater and the widening of Halema‘uma‘u itself are obvious. Starting in late May, the development of several cracks outside Halema‘uma‘u is clear, and inward slumping of a large portion of the western, southwestern, and northern crater rim begins. Much of this motion appears to be coincident with the small explosions from the summit that have taken place on a near daily basis since early June. The most recent radar scene, from August 1, shows continued motion along cracks over a broader area of the caldera floor, extending east of Halema‘uma‘u. We expect this slumping to continue as long as the collapse events and overall subsidence persist.”

Continue reading August 2: Word of the Day – ‘Tombolo’

July 28: Mini-Update Plus New Images of Summit

New Image of Halema’uma’u – July 28, 2018
July 28, 2018. USGS: “Aerial view of the summit crater from this morning’s overflight. Zoom in to see HVO and the Park’s Jaggar Museum on the caldera rim (right side of photo).” (Full-sized)

Note the light green mostly-treeless area in background at left, and then zoom in to find museum & observatory on rim at right. Then compare with:

April 13, 2018
BEFORE the big event: Kilauea caldera, April 13, 2018. USGS: “The museum and HVO are perched on the caldera rim (middle right), with the slopes of Mauna Loa visible in the background.” (Full-sized)
Today’s Eruption Summary

Summit collapse event at 2:37 am HST, July 28, 2018. Energy release equivalent to M5.4. Minor overflows on Fissure 8’s channel reported a few hours afterwards. At the coast, the SW edge of the flow remains stalled 175 m from Pohoiki boat ramp, with ocean entry a few hundred meters to its east.

Road crews are monitoring cracks on Highway 130 after increased gas emissions were detected there.

Also, notwithstanding longer intervals between recent summit collapses and a few days where the lava channel seemed lower, HVO doesn’t see any strong indications the eruption is weakening:

More photos from today

Continue reading July 28: Mini-Update Plus New Images of Summit

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.

Continue reading July 23: Pohoiki Going Tonight (I Think)

July 15: Tiny Island Is Now Tiny Peninsula

July 15, 2018. USGS: ” View of fissure 8 looking uprift toward the west. The open lava channel in upper right leads to the ocean; when the photo was taken this early morning, nearly all of the lava erupting from fissure 8 was in the channel. Some lava was spilling eastward to form a slowly advancing flow (middle foreground) atop earlier lava flows. This flow stalled within hours.” (Full-sized)
Today’s Eruption Summary

Kilauea’s double eruption continues as usual. Fissure 8’s lava river is still sending lava mostly to the southern ocean entry near Ahalanui, following the diverted channel on the west side of Kapoho Crater. The southern margin of the lava flow along the coast has slowed its southward advance, possibly giving Pohoiki/Isaac Hale Park a respite. At 7pm HST, HVO said it was “around half a mile away.”

July 15, 2018. USGS: ” Laze plume rises where lava pours into the sea on the south margin of the fissure 8 flow. This southern boundary did not change location appreciably in the past day, remaining about 900 m (0.56 mi) from the boat ramp at Isaac Hale Park.” (Full-sized)

The tiny island that formed Friday is now a tiny peninsula, joined to shore by a neck of lava or possibly just black sand. Lava continues to ooze into the ocean here and there along the broad front of 6 km (3.7mi) lava delta. Recent HVO Kilauea status alerts have warned that this delta has built out 0.5 miles from the former coastline, and is resting on “unconsolidated lava fragments and sand,” which can give way.

Following this morning’s 3:26 am collapse event (M5.2) at Kilauea’s summit, a pulse of lava came down the rift zone to Fissure 8. This caused an early-morning, temporary overflow to the ESE which did not extend beyond the boundaries of earlier flows. (This spillover was very visible during a 6:30am @hotseathawaii livestream overflight). No other vents show any activity.

USGS: “View of Halema‘uma‘u taken today (July 15) from the south side of the caldera near the KEANAKEKOI Overlook.” (Full-sized)

And a reminder of what it used to be like…

Continue reading July 15: Tiny Island Is Now Tiny Peninsula

July 11: Overflows and More Homes/Landmarks Lost

July 11, 2018. USGS: “A pāhoehoe flow fed by overflows from the fissure 8 lava channel was active along Nohea Street in the Leilani Estates subdivision this morning.” (Full-sized)
Today’s Eruption Summary

Quite a lot happened today in the LERZ. Fissure 8 started overflowing again about 8:30-9am this morning. Unfortunately, some spillouts on the north side extended past the edges of previous flows, destroying three more homes in Leilani Estates, two on Luana St, one on Nohea.

Another blockage just west of Kapoho Crater last night diverted much of the main lava channel around the west side of the crater’s cone, rejoining the main flow field on the other side. It created a channelized a’a flow which skirted the southern edge of the existing lava field, and was a quarter mile from the coast and Ahalanui Warm Pond by noon.  [Update 10pm HST: I’m seeing several unconfirmed reports on social media that it and Kua O Ka La Charter School were taken by lava late Wednesday afternoon or early evening.]

However, some lava is still being supplied to earlier ocean entry areas, either by still-molten lava that’s permeated the lava delta, or by a lesser supply of new lava following the old route around Kapoho Crater. This lava is working on building a point (it’s still not the easternmost point of the island, although the angle of the left-hand photo makes it appear so):

[full-sized left photo] [full-sized right photo]

Interestingly, today’s tardy summit collapse at 5:46am (M5.3 as usual) seems to have had some effect upon Fissure 8. There’s been speculation that might be occurring, but it wasn’t confirmed until now. According to the HVO update: “The collapse/explosive event this morning was followed by an increase in lava from the fissure 8 vent which has produced small overflows from the upper channel that are threatening a few homes on Nohea and Luana streets.”

July 11, 2018. USGS— in fact this is another Don Swanson photo, according to the FB caption: “A telephoto view of the eastern edge of Halema‘uma‘u taken just two minutes after today’s (July 11) 5:45 a.m. HST collapse explosion event. Steam is intermixed with minor ash that imparts a pinkish-brown color to the plume. The energy released by the event was equivalent to a magnitude-5.3 earthquake.” (Full-sized)

Fissure 22 continues to sputter quietly and intermittently, so the sluggish flow it was emitting a week or so ago has cooled.

July 11 LERZ Lava Flow Map
July 11, 2018. USGS map of LERZ lava flows as of 1pm. Full-sized)

Continue reading July 11: Overflows and More Homes/Landmarks Lost

July 10: Steve Brantley USGS Talk at Pahoa Meeting

Transcript of Steve Brantley’s Tuesday evening presentation at the weekly community meeting, July 10, 2018.

Steve Brantley (HVO/USGS): Well, good evening. Thank you for turning out. I worked really hard this afternoon to prepare my very best presentation for you tonight, and lo and behold, somehow it didn’t end up on my jump drive. So for that, I apologize. And what I’ll do is basically recount the presentation, but you’ll have to— we can refer to the map up here.

July 10, 2018, noon USGS map of lava flows. (Full-sized)

So the overall picture is that the activity at Fissure 8 has not fundamentally changed. A high rate of lava is still being erupted, and we really haven’t noticed a change in that rate. At the summit, the volcano continues to subside very slowly over time, and periodically— now about once every 30 hours, or almost every day— the ground drops as much as two and a half meters or so in each drop, and results in a ground shaking that’s equivalent to about a magnitude 5 event.

Continue reading July 10: Steve Brantley USGS Talk at Pahoa Meeting

July 3 Steve Brantley Slideshow at Pahoa Meeting

[Note: this is when the overflows around Kapoho Crater got started, but the main flow front/ocean entry was still mostly north.]

I was hoping NLTV would post a video of last Tuesday evening’s Pahoa Community meeting as they usually do, since BigIslandVideoNews records Steve Brantley’s slideshows by pointing the camera at him and skipping most of the slides, but no such luck.

BIVN posted various excerpts of the meeting, including these non-geology segments: Live poll, Hwy 130 Reopening Discussed, Residents question Civil Defense. 

Here’s Steve Brantley’s USGS presentation:

Transcript

Steve Brantley, Deputy Scientist-in-Charge of HVO:

Continue reading July 3 Steve Brantley Slideshow at Pahoa Meeting