Volcano thread

[bjdeming]

Very much a layperson opinion, but if lava were coming up, I think we would see more drum-beat quakes on the helicorder.

It looks to this layperson as though something gave way but then everything stabilized, at least for the moment.

 

[bjdeming]

Excerpt from a geoscientist a few minutes ago:

...
Nearly 800 earthquakes have been recorded since midnight. The largest earthquake measured 5.0 at 00:46 just west of Þorbjörn, and also the biggest earthquake of the collapse.


In addition, three earthquakes have been recorded at or above 4.0, the first at 00:13, it was 4.2 in size about 1.7 km east of Sýrlingafell, the second at At 02:56 a magnitude of 4.4 was measured in Bletthahrauni about 3.0 km WSW of Þorbirn. Then another one was measured this morning at 06:52, of magnitude 4.0 just east of Syrlingafell.


The earthquakes have been felt in many places in the Southwest corner.
Written by geoscientist on duty Nov 09 08:05

 

[bjdeming]

Just realized, with dawn breaking, that the RUV cam isn't live. FWIW, here is the Visir cam again --



and a multi-cam combo though I'm not sure of some of the locations (wish I knew where they get the earthquake graphic from!).

Just as an off chance, here is a stream from the general 2022 eruption site, as one of the volcanologists said after the recent CD meeting that they couldn't rule out activity here:



Thus far, there is nothing out of the ordinary going on anywhere.

 

[bjdeming]

Looking at volcanoes is so much fun; I have accidentally discovered that, while sitting here in the PNW in the middle of the night, at this time of year, I can:

1. Watch tomorrow's sunset over Sakurajima in Japan (here's the cam, if you want to try it) --



2. -- and then watch the coming morning's sunrise over Iceland on this east-facing cam:



And so to bed, a very happy camper.

 

[bjdeming]

Decade Volcano Ulawun in Papua New Guinea has gone off, with plume up to 50,000 feet (check second tweet for close-up):



Here's video uploaded five hours ago:



Since collapse is always a concern at Ulawun -- scroll down through the updates in this post to read a draft of the chapter on it in my Decade Volcano eBook -- I'm not surprised that
Japan experts were reportedly concerned about a possible tsunami; fortunately, that hasn’t materialized.

Nov. 21, 0034 UTC: About five hours ago, this Facebook post reported that the volcano was still going strong and evacuations were underway.

The image that accompanies it shows a standing volcano and a plume resembling those in images from Ulawun's previous VEI 4 eruptions. It's impossible to say what this eruption will turn out to be, since the volcano is apparently still going strong.

A plume to 50,000 feet is respectable, but we'll see how it goes.

This volcano is a big sulfur producer, too, so that's something to watch.

It is in a relatively remote region overall and Rabaul city is on the other side of New Britain Island, so folks who do need to leave can get out even though air flights, at least locally, are affected; haven't heard yet about international traffic.

Right now, it sounds serious but not unprecedented. Will keep an eye on it and add updates as needed.

 

[bjdeming]

Nice overview. As I understand it, there is now a fissure in the east/southeast flank, noisy, with ongoing lava flow.

 

[bjdeming]

This is real nice imagery of the entire eruption thus far, but reportedly there is an effusive fissure flank eruption, too.

 

[bjdeming]

Ulawun is at 5° S latitude.

 

[bjdeming]

Ulawun has calmed down, per reports on Facebook that also note some 13,000 people have been displaced.

(It's worth a passing mention that there is an international presence, including US Marines, on nearby Bougainville island, nominally to help relief efforts needed after Bagana -- that island's volcano -- erupted recently, but I suspect the island's strategic role in WWII has something to do with it also, in these tense times; the point is that it's likely that some international assistance from these forces might be helping those displaced by Ulawun on New Britain Island, in addition to the PNG government's efforts. Hope so, anyway.)

I'm still looking up news on reports of effusive flank eruptions, a question related to edifice stability that might go unanswered until the next few GVP activity reports.

Overall, to this layperson it looks to have been another large eruption along 2019 lines.

The first post in this thread below has a flight-level view of the plume's effect on weather clouds:



I am uncertain of the exact details, but overall the plume -- quite hot, if I understand those Indonesian VRP graphs -- is entraining air, which then convects and lifts the plume higher.

 

[bjdeming]

 

[bjdeming]

It's visible from space already!

 

[bjdeming]

In 2019, Ulawun had some help from a high-sulfur eruption in the Kuriles, resulting in slightly purple sunsets. This time around, as Dr. Carn noted, there aren't likely to be such atmospheric effects.

Still, this is cool:

 

[bjdeming]

Just a visual update on Ulawun's recent eruption (BTW, I don't understand why it has both powerful explosive AND strong effusive activity in the same eruption):



At last report, it was sputtering a bit but, if this follows the 2019 pattern, it will settle down.

 

[bjdeming]

However, while looking into nearby Bagana, which has had upticks in SO2 lately, per TROPOMI SO2 tweets (I refuse to call them posts), I found this.

No, not local conditions in Beaverton, Oregon (it is nippy here in Oregon tonight, but snow free):

Ulawun is still producing a lot of SO2, as well -- which it's known to do -- but I think the worst cloud is from the explosive eruption.

EMB Caraga in the Philippines posted this about an hour ago, saying that they are watching it but right now air quality is good.

And I'm not sure how to connect that up with this, posted above.

 

[bjdeming]

Krakatoa, a/k/a Krakatau -- out in the Sunda Strait between Sumatra and Java -- has been active off and on down through the last hundred years.

I got superexcited about it upon learning that, but soon learned that this is what the volcano does: blows itself to pieces as in 1883, and then slowly rebuilds itself through fairly small eruptions; blows itself to pieces again; rinse and repeat.

It's in the reconstruction phase now and having a series of rather powerful vulcanian pops, but that's all part of the pattern (though the volcano still is deadly).

Saw this satellite photo, though, and wanted to share it because of the view directly over the volcano.

The plume is coming up from the new young volcano that formed in the 20th century. You see all that water, surrounded by islands, around and under the plume?

That used to all be an island, and that is what exploded in 1883. This view gives us some idea of the scale of that event.



What is erupting now is "Son of Krakatau" -- Anak Krakatau. It breached the surface between 1927 and 1929, and some young Dutch geologists filmed the event.

Don't know if anyone will care to watch the whole video, which has a lot of closeups of rocks, is silent, and with Dutch titles here and there, but there are interesting views of another world, another time, and you might enjoy the biplane sequences, complete with selfies!

Ah, yes -- and the explosions. Lots and lots of Surtseyan eruptions.


I love it. Here it is:




For contrast, Naked Science made a film, shortly after Indonesia's bad tsunami, that intermingles modern-day fact and a recreation of the 1883 blast that's a little too overdramatized in terms of characters IMO but good with the basic eruption details.

Also, the team visits Anak Krakatau as it was before the 2018 flank collapse. Looks quite different from the Dutch open cockpit days, no?

Volcanoes are changeful places.

Krakatau isn't going to do this again any time soon, but since this eruption is so famous and the volcano is active at the moment, I thought a post about it would be timely.

Maybe this has already been shared, but it does go well with the current overhead satellite image showing water where this island used to be:

 

[bjdeming]

Ulawun update from the Smithsonian's Global Volcanism Program (GVP), November 22-28:

Rabaul Volcano Observatory (RVO) reported that white steam plumes and occasional puffs of ash rose from Ulawun’s summit crater during 22-24 November, though weather clouds hindered views during 23-24 November. Lava continued to flow from a new fissure vent that had opened on the SW flank, near the vent that had formed in 2019. The intensity of the incandescence from the flow decreased during 23-24 November, suggesting that effusion may have slowed. Seismicity remained at background levels. The Alert Level remained at Stage 2 (on the four-level scale).

A magnitude 6-plus quake happened north of Papua New Guinea during that interval, but it doesn't sound as though the volcano was affected.

As for the sulfur complaints up in the Philippines, there is no more news on Facebook or Twitter, and EMB Caraga has not issued any updates, so ?

Of note, Taal volcano, at the southern tip of Luzon, has been producing a lot of SO2 lately and had at least one day of five-digit emissions (glad that didn't happen during the inversion that be-smogged Manila recently).

I don't know anything about air circulation patterns in the Philippines, but perhaps the culprit might have been Taal (or some other local volcano), not Ulawun.

On the human level, USAID is helping out from Port Moresby.

Per local news reports, this palm oil company was on the scene with aid even before Ulawun had calmed down -- and even though they took a serious hit:

 

[bjdeming]

The waiting continues. This layperson's impression from IMO updates and news reports is that the wait will end after the sill fills up again and the earthquakes restart. But then no one can be sure where the magma will go, per IMO interviews with local press, though east to the dike area seems most likely. There are proponents of a westward breakout, too, in the Eldsvorp system.

Grindvikings have been accessing their property between 9 and 4 daily but reportedly won't be allowed back in to stay until the dike's magma inflow stops -- it is still going on, though much weaker, around the Sylingafjall/Hagafall area a few kilometers north of town.

That access might change, though, because this just happened:



Well, technically, they discovered it yesterday.

And reportedly (autotranslated) the whole Reykjanes Peninsula has cracked up a bit -- nothing like in Grindavik, of course, but the quakes have opened up cracks and fissures. Keilir, that pyramid of a mountain near the Litli Hurtur eruption site, is shedding large rocks from its summit and apparently a fissure has opened up near a sea cliff, which may collapse as a result.

This photo is from that linked article:

Part of the crack at Krýsuvíkurbjarg.
RÚV – Gunnhildur Kjerúlf Birgisdóttir

There are huge traces all over the Reykjanes Peninsula from the earthquakes that have occurred there. At Krýsuvíkurbjarg, the ground seems to be about to fall into the sea, and the police are warning the public against traveling in the area...

Interesting times.

Here's the live cam where, in daylight, you can see Keilir's details -- a cam is probably the safest way to visit it these days:



I believe that's Reykjavik in the background -- the city wasn't at all threatened by the earlier Fires but was close enough to serve as a base for the many international visitors who came in to visit 2021-2023 eruption sites on foot or by bus.

The Good Times of volcano tourism for Iceland; now Earth is presenting the bill.

 

[bjdeming]

No one needs to be warned about respecting these polygons!



Second only to the Hunga Tonga blast in terms of awesome volcano imagery I've seen thus far.

Per PHIVOLCS, the pH of that small crater lake is 0.45 (it's on Volcano Island which in turn is surrounded by the great Taal Lake filling the caldera (which is perfectly normal lake water).

 

[bjdeming]

Sumatra's most most active volcano reminded everyone it is still there today --



Reportedly there were 70 hikers checked into the area and 42 of them are still unaccounted for.

GVP page.

 

[bjdeming]

Just did a news check. Reportedly:

• 75 were on the volcano
• 3 of the missing found alive
• 11 dead
• 12 still missing

Of note, AFAIK Marapi is still erupting, and the news article reports 160 people involved in the search and rescue effort.

Confirmation: Yes, still erupting; this was posted an hour ago:



There was also this from last night (local time); I don't know what the man says at the end, but from his face I gather that he is giving us the bad news contained in the news article up above.