Meanwhile, at Kilauea . . .


Update, November 24, 2018, 7:26 a.m., Pacific: Per the volcanologists, who kindly replied by email, this cloud coming out of the caldera, captured on the cam shot (below), was:

Volcanic gases — visibility of plume is more pronounced in early mornings and evenings when warm gases condense as they are released into cooler air temperatures. See this week’s Volcano Watch article for more info: https://volcanoes.usgs.gov/observatories/hvo/hvo_volcano_watch.html

We, outside Hawaii, forget that the air cools down more there, this time of year, just like where we are.

Check out the article: it turns out that local people are still dealing with a sulfur smell, only this time it’s the “rotten-egg” smell. Pelee, that’s not polite!


New featured image: Rainbow in Kilauea Iki crater this summer, by Heath Cajandig, CC BY 2.0


Update, 8:34 p.m., Pacific: Well, this is weird. Per the 6:59 p.m. note below, all is clear per VAAC; no updates on the HVO web page (linked in original post) or the Hawaii CD tweets; nothing on KHNL.

And yet I saw this on the summit cam; fortunately I saved it, because the next cam update was a black screen (night time, nothing unusual–all the other cams were already black).

??



It’s difficult for experts and impossible for a layperson to tell what’s going on in such scenes from just one static image, especially with such lighting. That could conceivably be weather (note the cloudy sky), but it seems to be coming up out of the summit caldera.

Well, we can but wait and see . . . and send an email to the “ask HVO” hotline. Will pass along any replies.


Update, 6:59 p.m., Pacific: About four hours ago, the VAAC issued an all-clear. No other changes; Kilauea remains at Yellow aviation code. We’ll see what HVO says in its next weekly update.

Yes, Kilauea is monitored very closely, and not just because of its Lower East Rift Zone eruption earlier this year. It’s the #1 most hazardous volcano in the US.


Original post:

Washington VAAC reports possible volcanic ash emission, perhaps mostly steam, extending 5 nautical miles from summit. HVO hasn’t updated or issued a VAN (Volcanic Activity Notice) yet. I looked at the webcams, and saw nothing that looked like remobilized volcanic ash from this year’s earlier eruptions. Nothing about it yet on the Hawaii CD Twitter feed or KHNL, either.

Here’s the current webcam view at Pu’u O’o:



That may just be typical for this empty crater in the middle of the Lower East Rift Zone just now.

All of those links are given so you can follow this, too. It doesn’t seem like a sudden return of eruptive activity at Kilauea, but you never know. Will add any significant changes today below, if any occur.


Featured image: geralt at Pixabay.



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Meanwhile, in Alaska . . .


Update, November 22, 2018, 12:51 p.m., Pacific: Happy Thanksgiving! Also, AVO has decreased the alert level back to Orange, as Veniaminof’s ash emissions have decreased in intensity, though they continue (along with the flowing red lava.


Original post:

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This was a Sunday Morning Volcano back in October, with a beautiful video of a molten flow down the volcano’s steep flank. Some volcanoes are capable of both Hawaiian-style “red lava” and explosive “gray lava” activity.

Veniaminof is way out in the Aleutian chain, though close to some small communities. The major problem with this and any Alaskan volcano’s typical eruptive activity–not talking extreme stuff like Novarupta/Katmai last century–is that aviation great-circle routes pass overhead and carry lots of traffic.

Here is the VAAC list of advisories Continue reading

Guest Video: Öræfajökull


Update, October 26, 2018: Volcanologist Erik Klemetti has a good blog post up about this volcano. Should we be worried? A resounding no, he says. At least not right now.


Original post:

Let’s all start practicing this new Icelandic name now, just in case this restless volcano does go off in our lifetimes!



Given Öræfajökull’s size and its history, an eruption could be bad (though you never know what a volcano is going to do until it does it).

There are a lot of gloom-and-doom videos and sites out there, but here are some online information sources I’ve found reliable:

  • Icelandic Met Office
  • The Smithsonian’s GVP page.
  • Various posts by Dr. Erik Klemetti, including this one, and this.
  • Jón Frímann Jónsson–an interesting though not expert lay source whom many of us online volcanophiles relied upon during the lead-in to the 2010 eruption of Eyjafjalljökull.
  • London Volcanic Ash Advisory Centre (VAAC) website. This should be the first place you check, if you want to know if Öræfajökull has really erupted. The link to Toulouse VAAC on this page is also helpful.

Featured image: Satellite image of Öræfajökull, showing cauldron of glacial meltwater in late 2017. Antti Lipponen, CC BY 2.0.


Guest Video: Volcanoes and Glaciers


Did you know that Yellowstone Supervolcano was covered by some 4,000 feet of ice during the last ice age?

According to the Yellowstone Volcano Observatory (YVO), the hydrothermal system at the volcano really “lit up” after all that ice melted away.

But what would have happened had the volcano erupted while a glacier sat on it?

Continue reading

Kilauea Update


There has been a slight, but possibly very important, change in the eruption–less lava coming out in the Lower East Rift Zone and a hiatus in summit collapse events–and I’m updating the Kilauea eruption page again. Can’t spend a lot of time on it because of book work, but I’ll try to catch the important stuff. Right now it’s mostly waiting to see the next pronouncement from USGS/HVO.

Click the link at the upper right of this page or use this one.

You’ve seen plenty of video of the lava flowing in the LERZ, so here is a USGS video of a summit collapse event about two months into the eruption. It’s not dramatic to look at–just trees shaking as the seismic waves roll through–but it is every bit as much of a caldera collapse as something CGI’d in a supervolcano movie.

Only it’s in real life, and happening so slowly that we can watch it in relative safety, while carrying on with our lives as usual nearby. And there hasn’t been one of these otherwise daily occurrences since August 2nd; it may never happen again our lifetime. (Then again, it might–you can’t be sure of anything around Pelee!)



Featured image: USGS/Hawaiian Volcano Observatory


Guest Videos: Laguna del Maule Volcanic Complex


First off, here’s a skiing video, without a single mention of volcanoes. But everything they are travelling over, under, around and through is part of the Laguna del Maule volcano complex on the Chile-Argentina border.



Yes, it’s an active volcano. In fact, until last year it seemed the most likely candidate for the world’s next supereruption.

Continue reading

Livestream of Kilauea’s Summit Crater


The lava fountains and human drama in Hawaii’s Lower Puna District are getting all the headlines, but geologists know there is also drama ongoing at the summit, where the volcano’s crater seems to have been slowly collapsing since the lava lake drained.

Hawaiian Volcano Observatory staff were forced to move farther away from the summit area because the many earthquakes there were damaging the building. Now, they have set up a livestream, and it’s fascinating to watch. Basically, the crater walls are slowly crumbling inward, and there is a pile of rocks at the bottom that may be suppressing the explosions — after a period of suppression, of course, there will likely be a big steam blast to relieve pressure, But no one knows if or when that will happen, or what will happen next.

Anyway, here’s the livestream:




For comparison, here’s a video they recorded in March to mark the ten-year anniversary of the lava lake first appearing in the summit crater. Where he’s standing has already collapsed now.



Here is a drone overlight of Halemaumau they did on May 31st. As you can see, the vent where the lava lake used to be has expanded to almost fill the whole crater. And there’s the rock pile down at the bottom, probably supressing, to some extent, the explosions.



And, about an hour ago, the USGS posted this:


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Featured image: USGS. Those curved lines on the left is where the visitor’s parking lot used to be.


Havre Seamount

You need this background to the recent news that, at Havre Seamount near New Zealand, scientists have found the largest deep-water silicic eruption in history. Some cool videos of eruptions are included, too.

Thanks to plate tectonics, almost three-quarters of Earth’s lava is erupted in the oceans, at mid-ocean ridges, not on the land where we can see it.

These spreading ridges, as they are called, are really a high volcanic mountain range rising from the abyssal depths and running down the middle of just about every ocean on the planet.

Most of that lava and rock is mafic – a word coined from the chemical symbols for magnesium and iron, which enrich this type of magma and make the resulting rock dark.

This runny red stuff usually erupts quietly as pillow lava, but in relatively shallow water, mixing molten rock and good old H2O can be spectacularly explosive.

That is the 1963 Surtsey eruption, off Iceland’s southern coast. This volcano sits in the middle of the Atlantic, but since it’s on a coastal shelf (and therefore atop the Mid-Atlantic Ridge, along with Iceland), ocean depth there is measured in hundreds of feet, not miles.

Even so, scientists would have had a hard time studying the eruption if it hadn’t broken through to the air.

Surtsey is made out of mafic rock. Another type of dramatic volcano comes from silicic magma – it contains a lot of silica instead of magnesium and iron.

Usually you find silicic volcanoes near the coast, as in the High Cascades of the US Pacific Northwest. They form in such places because, offshore, a seafloor plate is sinking down into the depths of the Earth and the continental plate is riding over it.

Of course, it’s hot down there in the mantle. Not only that, seawater is mixed in with the sinking rock – this lowers the melting temperature and causes chemical reactions that, among other things, make the silicic magma very sticky.

Volcanoes form wherever this magma reaches the surface near the trench made by the sinking plate edge.

The eruption may be explosive, as when gases build up a lot of pressure. Without so much gas, it can be nonexplosive but gooey, as in the Mount St. Helens eruption that began in 2004.

Here is a USGS closeup view of how Mount St. Helens rebuilt itself between 2004 and 2008:

Sometimes subduction (one tectonic plate sinking underneath another) happens far from land.

Volcanologists know this, but they haven’t been able to learn much about the resulting silicic volcanoes, since it all happens in deep water, which is technically defined as more than 500 meters, or over a third of a mile, below the surface.

The pressure of water at those depths is enough to prevent Surtsey-like blow-ups, so evidence of these eruptions usually goes unseen.

In 2012, though, volcanologists were able to trace a raft of pumice that had been sighted by satellite – see the image at the top of the page – back to Havre Seamount in the general vicinity of the Kermadec Islands.

That in itself was big news, but now technology has also enabled volcanologists to visit the volcano.

That is what all the fuss is about today!

Here is the original University of Tasmania fly-through used by Scientific American in the above video:

As of this writing, the Smithsonian doesn’t have a picture of Havre for the volcano’s GVP page. That’s going to change soon, thanks to this major volcanological success!


Featured image: Havre’s pumice raft spreads across the sea, NASA.


Sources:
Carey, R.; Adam-Soule, S.; Manga, M.; White, J. D. L.; and others. 2018. The largest deep-ocean silicic volcanic eruption of the past century. Science Advances. 4(1):e1701121.

Jakobsson, S. P.; Thors, K.; Vésteinsson, A. T.; and Ásbjörnsdóttir. 2009. Some aspects of the seafloor morphology at Surtsey volcano: The new multibeam bathymetric survey of 2007. Surtsey Research. 12:9-20.