Volcano thread

[bjdeming]

Nope. There it goes again. (BTW, there's an Addicted trophy? )

Edit: And so to bed. Whew! It seemed to come on through that righthand side. Earlier in the afternoon, I did see some emissions on the left (Cam C), but maybe that's still mostly blocked?

 

[bjdeming]

There it goes again. It's late; I'm tired. Will only post more tonight if it escalates big time (i.e., if these are just throat-clearing events, which seems unlikely right now given the lack of oomph shown currently).

I don't recall seeing this behavior from Sakurajima in the very short time I've followed it (about three years).

 

[bjdeming]

New day, one blast noted by Tokyo VAAC overnight (Pacific time), and as far I can tell from the cams at 4 a.m., local, Sakurajima is erupting again.

This is a change in pattern, and since it's eruptions, I think it deserves its own thread.

 

[bjdeming]

So, there's this young supervolcano just the other side of the mountain from Modesto (and many other urban areas):



It is closely monitored. (An excellent book called Fire Mountains of the West has a good account of the Mammoth Mountain swarm there in the 1980s that made geologists very unpopular at the resort for a while and also led to the USGS volcano alert system.)

It is in the news these days. There are other studies. I don't know much about it other than:

1. It's not likely to erupt big time in our lives. They have it listed as high threat because of all the people at risk, etc., not because it's cranking up (it isn't).
2. The most likely next eruption site will probably near Mono-Inyo Craters, and about their scale, not supersized.
3. Long Valley Caldera is in a very complex tectonic regime (which is why I haven't tackled it for the blog yet; it's challenging for scientists and more so for this layperson).
4. There is a school of thought that seismicity in the caldera can be attributed, to some extent, to hydrologic factors associated with nearby mountains. ? how this fits in with the CIT and other studies.

I'd like to learn more about it.

 

[bjdeming]

Iwo Jima is erupting. This is not new, but it's worth mentioning because of the historical context.

It is in a caldera that's been inflating big time: ships sunk during the 1945 battle emerged in 2021 and the land where Captain Cook set foot back in the day is now 40 m above sea level.

No caldera-forming eruption is expected any time soon AFAIK -- the eruptions now are surtseyan.

If you don't mind Italian (Twitter translates it):

 

[bjdeming]

 

[bjdeming]

Here's a better shot -- per Twitter translation, Iwo Jima is that land behind the active vent (but it is all within the caldera).

 

[bjdeming]

Iceland's eruptions lately -- those near Fagradalsfjall -- have been gorgeous lava fests but out in the boonies.

Another one is looming, this time apparently near an inhabited area (but not near Reykjavik).

• Icelandic Met Office, (autotranslated).
• IMO geoscientist notes, (autotranslated).
• Layperson Jón Frímann’s blog.
• IMO data and link to Norwegian Meteorological Office data (autotranslated).
• Icelandic Volcanoes Twitter feed.

 

[bjdeming]

From two hours ago (? precise location):

 

[bjdeming]

It's usually fun to watch an eruption come in Iceland -- like watching a textbook exercise play out in real life.

Not so much now.




It's not a major metro area, though important --

Grindavik, south of highlighted area; check YouTube for harrowing videos of fishing boats coming into the harbor during winter storms.​

-- but there also is the Blue Lagoon nearby (and a geothermal energy plant) just north:



At least people in the area aren't on a small island with the eruption as some were on Haemey (? sp) in the 70s (the one where they poured sea water on the lava and saved a harbor).

 

[bjdeming]

This is what Icelanders do in the run-up to an eruption (those not in a potential eruption zone; per tweets, Grindavik is getting generators, etc., and as above, prep for possible evacuation):



I'd go with more soothing music...

 

[bjdeming]

Well this IMO update is gob-smacking, as is the reported rate of land rise. The magma is basically ponding under the area (a sill is "horizontal" in terms of not moving towards the surface, as dikes do -- AFAIK, the other Fagradalsfjall eruptions were dike-fed):

Updated November 6 at: 12:40 p.m



In the last 24 hours, about 1,300 earthquakes have been recorded on the Reykjanes Peninsula, of which three earthquakes are over magnitude 3. The largest earthquake occurred about 3 km NE of Þorbjörn and measured 3.6 at around 7 this morning.

Deformation measurements show that landris continues in the area NW of Þorbjörn and there are indications of an increased rate of expansion since Friday, November 3. Since October 27, land has risen by 7 cm according to GPS measuring station in Þorbirn. The deformation is caused by the accumulation of magma in a sill at a depth of about 5 km. According to updated model calculations, based on data from October 27 to November 3, the shelf has become twice as large as the four shelves that have formed at Þorbjörn since 2020. Inflow into the shelf is estimated at 7 m3/s, which is four times faster than previous clip with Þorbjörn.

While the magma accumulation continues, seismic activity can be expected on the Reykjanes Peninsula because the magma intrusion causes increased tension in the area.

Here is an autotranslated link to mbl.is's topic page. This article, in particular, is interesting.

 

[bjdeming]

Still "NEI!" on any eruption. Just wanted to share a link to RUV's cam at Thornbjörn, which I think is close to the center of all these Fagradalsfjall "fires."

It's good to get a little familiar with an area, I've learned, before the lava appears.

Also: https://www.volcanocafe.org/thorbjorn-on-the-brink/

 

[bjdeming]

Still NEI! Just a news update: I believe RUV is their public broadcasting service.



Yes, a couple of people have tweeted about the Blue Lagoon staying open. I couldn't do it -- that scene in Dante's Peak would play over and over in my head.

 

[bjdeming]

There's a plethora of webcams that always come online at times like these. RUV is reliable, but they haven't put it on YouTube yet.

When lava erupts I'll put all the cams with good views and other links in the first post of that thread (or someone else can if they want to -- am just enthusiastic)

Visir (autotranslated) is good, too; they have this one up now. It's located atop Mount Thorbjorn and overlooks the Blue Lagoon and that inland part of the peninsula.

Yeah: the Blue Lagoon and Thorbjorn are almost right at the center of the seismicity. And they're keeping that place open; granted it might not exist soon, but still...!

Cam:

 

[bjdeming]

Nothing yet; in fact, some tweeters report a very quiet night so far, which can be either good or bad in such a situation.

Anyway, I got together information about the series of Fagradalsfjall eruptions thus far: basically some videos (so everyone can go, "Yeah I saw that on the news a couple years ago") along with some Global Volcanism Program reports, and IMO and Civil Defense press conference for the current crisis:

Guest Videos: The Fagradalsfjall Fires to Date

With a potentially very large eruption from this system looming, now is a good time to review the “fires” — a term used locally for any series of eruptions from a given volcanic s…

flighttowonder.com

It's really just a backgrounder; good luck with the GVP links -- I use the URL on the page where I am getting the information, but when I test the links, they don't always go there.

The GVP weekly and bulletin reports still will get you to lots of good information.

The last news I saw was that an eruption could happen anywhere from the 2022 Fagradalsfjall site to the Thorbjorn area. If this quiet keeps on, perhaps the sill will stall. These rocks have been quiet for some eight centuries, after all, and there might not be any vertical cracks to exploit.

What we don't want is an earthquake right now, and one is likelier with all that ground deformation.

 

[bjdeming]

About two hours ago, here (autotranslated):

Comments of a geoscientist​

Just after midnight, a powerful storm started near Þorbjörn and Sýlingafell with an earthquake of magnitude 3.9. at 00:02. At 00:13 another earthquake of magnitude 4.2 was recorded and at At 00:46, the largest earthquake measured almost 5.0 in magnitude. About 400 earthquakes have been recorded, of which 18 were over three in magnitude recently at 02:56, 4.3 in size. The earthquakes have been felt in many places in the Southwest corner.

More than 22,800 earthquakes have been recorded in the earthquake series that began on October 25 at Þorbjörn. A total of six earthquakes have been measured above magnitude 4, the largest measured magnitude 4.5 at 8:18 on 25/10. More information about the earthworks in the news on the front page

The National Police Commissioner in consultation with the police chief in Suðurnesj has declared the level of uncertainty for Civil Defense due to the earthquake. See news
Written by geoscientist on duty Nov 09 03:36

The RUV cam is panning and so far shows nothing but electric lights at Blue Lagoon, the power station, and (I think) Grindavik in the distance.

Unrelated, but I noticed in this week's earthquake report that there is a magma intrusion under Fagradalsfjall, too, but much deeper: 10 km.

 

[bjdeming]

Today's IMO report (autotranslated) has an amazing image of the widespread deformation:

 

[bjdeming]

Jón Frimann's opinion (he is an informed layperson, too, but much more familiar with Iceland and a veteran of several eruptions there):

It is unclear if this earthquake activity is the start of the eruption or just normal inflation related earthquake activity. The magma is still at depth of 5 km. If it has started to move upwards trough the crust, it is going to take several hours to reach the surface. That means nothing might happen on the surface until late tomorrow or on 10. November at the earliest. Depending on how quickly the magma goes up through the crust.

 

[bjdeming]