Supervolcanoes: there are 11 worldwide/ FIVE in the US (no kidding!)

[Seabird]

Intrigued with the science of Supervolcanoes, the following was discovered. There are 11 known supervolcanos, five of which are in the USA; four on the main continent, one in Alaska. This was very surprising. All have the same characteristic hot springs and geysers. Check out the link to get information on each caldera.



http://www.answers.com/topic/supervolcano&method=8


Mount Aniakchak, Alaska, United States
Aso, Kyūshū, Japan
Campi Flegrei, Campania, Italy
Kikai Caldera, Ryūkyū Islands, Japan
Long Valley Caldera, California, United States
Mount Mazama, Oregon, United States (now Crater Lake)
Lake Taupo, North Island, New Zealand
Lake Toba, Sumatra, Indonesia
Valle Grande, New Mexico, United States
Mount Warning, New South Wales, Australia
Yellowstone Caldera, Wyoming, United States

 

[sssarawolf]

Wow

I didnt realize there were so many, in the U.S.

 

[Seabird]

I didnt realize there were so many, in the U.S.

Neither did I, Sssarawolf. There has been so much discussion of Yellowstone, yet the Alaska Caldera is more active being directly on the Pacific Ring of Fire. And the other three in California, Oregon and New Mexico are awfully close together, not to mention how close they are to the Ring of Fire. Really, Yellowstone is pretty far from being directly connected to the ring, although, it is a tad unnerving that the Alaskan volcanic activitiy has effected the Yellowstone caldera in the last few years.

It's interesting that New Zealand's caldera and Australia's caldera are also on the ring of fire, as is the TWO in Japan (man, that's a very small place to have two supervolcanoes. Yikes! ) And of course, Toba (Indonesia) in on the ring. It's odd that only Italy's caldera is completely off the Pacific grid.

Seabird

 

[Karnie]

It's odd that only Italy's caldera is completely off the Pacific grid.

Seabird

I understand that Italy's caldera used to be on the grid, but during the lead-up to Y2K, it decided to practice full self sufficiency. Therefore it packed up and moved off the grid entirely. It's now powered by a bank of solar panels.



I guess I should be looking for somewhere to hide now....

Karnie

 

[Freeholdfarm]

I didn't know Mt. Mazama was a supervolcano! Crater Lake is only about fifty or sixty miles north of us, and a good chunk of the houses in town (Klamath Falls) use geothermal heat -- I wonder if that means we are actually on top of the supervolcano!!


Kathleen

 

[Jumpy Frog]

Long Valley is just over the hill from me. The Geo classes here at the campus head over every year for a week long trip of hot springs and hands on teaching.

 

[Gordana]

I understand that Italy's caldera used to be on the grid, but during the lead-up to Y2K, it decided to practice full self sufficiency. Therefore it packed up and moved off the grid entirely. It's now powered by a bank of solar panels.



I guess I should be looking for somewhere to hide now....

Karnie

That's a good one, Karnie.

 

[Seabird]

I didn't know Mt. Mazama was a supervolcano! Crater Lake is only about fifty or sixty miles north of us, and a good chunk of the houses in town (Klamath Falls) use geothermal heat -- I wonder if that means we are actually on top of the supervolcano!!


Kathleen

Kathleen,

I was shocked that there are so many places in such a limited area of the US.

Even though Mazama is so close to you, it hasn't been active which makes me think that with the global crust shifting, the magma under you is actually moving eastward. There's a lot to learn with all of this.


And Karnie, you crack me up!


Seabird

 

[Old Gray Mare]

Fair use.

Report on Aniakchak (United States) — 22 February-28 February 2023​

Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
22 February-28 February 2023
Managing Editor: Sally Kuhn Sennert
Please cite this report as:

Global Volcanism Program, 2023. Report on Aniakchak (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 22 February-28 February 2023. Smithsonian Institution and US Geological Survey.
Weekly Report (22 February-28 February 2023)

Aniakchak​

United States​

56.88°N, 158.17°W; summit elev. 1341 m​

All times are local (unless otherwise noted)​

On 22 February AVO raised the Aviation Color Code for Aniakchak to Yellow (the second lowest level on a four-color scale) and the Volcano Alert Level to Advisory (the second lowest level on a four-level scale) due to a recent increase in the number of earthquakes and a shallowing of those events. Background seismicity was generally characterized as deep (more than 15 km below sea level) long-period events occurring at a rate of about four events per month. Beginning in October 2022 the rate increased, and the earthquakes were located at depths less than 9 km below sea level. The earthquake rate further increased on 31 January and was sustained with dozens of earthquakes detected per day, including a M 3.7 earthquake recorded on 17 February.

Elevated seismicity continued during 23-27 February at a variable rate. Dozens of earthquakes were recorded daily during 22-26 February, though more than one hundred small earthquakes (not all locatable) were detected during 24-25 February. Small earthquakes occurred at the rate of about 10 per hour during 26-28 February. AVO noted that there was no indication that an eruption of Aniakchak was imminent, or that one will occur. Increases in seismic activity have been detected previously at other similar volcanoes, with no subsequent eruptions.

Geological Summary. One of the most dramatic calderas of the Aleutian arc, the 10-km-wide Aniakchak caldera formed around 3,400 years ago during a voluminous eruption in which pyroclastic flows traveled more than 50 km N to the Bering Sea and also reached the Pacific Ocean to the south. At least 40 explosive eruptions have been documented during the past 10,000 years, making it the most active volcano of the eastern Aleutian arc. A dominantly andesitic pre-caldera volcano was constructed above basement Mesozoic and Tertiary sedimentary rocks that are exposed in the caldera walls to elevations of about 610 m. The ice-free caldera floor contains many pyroclastic cones, tuff cones, maars, and lava domes. Surprise Lake on the NE side drains through The Gates, a steep-walled breach on the east side of the 1-km-high caldera rim that was the site of catastrophic draining of a once larger lake about 1850 years BP. Vent Mountain and Half Cone are two long-lived vents on the south-central and NW caldera floor, respectively. The first and only confirmed historical eruption took place in 1931 from vents on the west and SW caldera floor.

Source: US Geological Survey Alaska Volcano Observatory (AVO)

Link to source:

Global Volcanism Program | Report on Aniakchak (United States) — 22 February-28 February 2023

Volcano report from the Smithsonian's Global Volcanism Program (GVP).

volcano.si.edu

 

[packyderms_wife]

Fair use.

Report on Aniakchak (United States) — 22 February-28 February 2023​

Well this isn't good, if it blows in a big way it'll definitely affect our weather here in the lower 48.

 

[Old Gray Mare]

Well this isn't good, if it blows in a big way it'll definitely affect our weather here in the lower 48.

Yup. That's why we post stuff like this. That's why lurkers come here to find info they're not going to see or read on legacy media.

 

[Profit of Doom]

I didn't know Mt. Mazama was a supervolcano! Crater Lake is only about fifty or sixty miles north of us, and a good chunk of the houses in town (Klamath Falls) use geothermal heat -- I wonder if that means we are actually on top of the supervolcano!!


Kathleen

At least near the magma plume. Relatively speaking.