As of November 20th, 2022, there are 47 volcanoes which are actively erupting across 7 continents.
In the last week, several volcanoes produced new eruptions while others had their alert
levels raised due to signs of unrest.
Here are this week's major volcano related news stories.
On the border of Chile and Argentina, a new explosive eruption began from the Copahue
volcano, scattering a large amount of ash to the east.
Meanwhile, in the U.S. Northern Mariana Islands, a submarine volcanic eruption was discovered
to be most likely ongoing due to various sensor readings, leading to discolored water in the
region.
And, in the nation of Vanuatu, the Ambrym volcano is once again showing signs of unrest
via a likely fresh intrusion of magma within the volcano's caldera.
For context, the Ambrym volcano encompasses the entire island which it is on, and just
like volcanoes on Hawaii's big island, it is a type of shield volcano due to its overall
gentle slopes and broad profile.
However, like the Emi Koussi volcano in the nation of Chad, Ambrym is no ordinary shield
volcano as it is not primarily built by effusive eruptions.
Instead, it is a rare type of volcano known as a pyroclastic shield where large volume
explosive eruptions with broad but low plinian eruption columns scatter ash over a wide area,
creating a shield profile.
The most recent large scale explosive eruption to originate from Ambrym occurred around 20
CE, when an eruption which was at least 20 times larger than the 1980 eruption of Mount
Saint Helens occurred.
This eruption not only wiped out the majority of life on the island, but also created a
12.3 kilometer or 7.6 mile wide depression in the ground known as a caldera.
Post caldera eruptions have been only moderately explosive, building abundant vents, the last
of which occurred in January of 2022.
Well, as of earlier this week, satellite sensors detected ground deformation totaling as much
as 8 centimeters in the past month in the eastern section of its caldera.
This is quite worrying for the following reason.
When Ambrym erupted in 2018, it created a series of cracks and fissures across the eastern
rift zone, uplifting areas by as much as a meter or 3 feet, even right through buildings.
These areas now represent weak points where the next flank eruption could occur, and as
a result the local volcano agency designated a 500 meter exclusion zone around each of
these vents.
The worry is that since there is likely a fresh magma intrusion present in the eastern
section of the caldera, it would not take much for the material to start propagating
eastwards and erupting where several settlements are located.
Luckily, no signs of this occurring have yet been detected, but the distinct possibility
that it does occur remains.
Of course, a similar episode of uplift slightly further north of the ongoing uplift occurred
in June of this year and that did not result in a new eruption.
Meanwhile, on the border of Chile and Argentina, a new explosive eruption occurred at the Copahue
volcano on November 16th, sending a plume of ash into the air.
Satellites subsequently detected heat signatures from the volcano indicating a magmatic component.
The ash from the eruption drifted largely to the east southeast, coating several areas
including an airport with a layer of finely grained volcanic particles.
This new eruption has the potential to effect towns on both sides of the border and could
continue for anywhere between a few more hours to a few more months.
In the Northern Mariana Islands, the U.S. Geological Survey had for about a month been
tracking hydroacoustic signals originating from around the Farallon De Pajaros volcano.
These signals were consistent with a volcanic eruption, which became mostly confirmed on
November 6th, when satellite imagery showed discolored water originating from the shallow
submarine volcano known as Ahyi to the south.
However, due to a lack of sensors it is unclear where on the volcano the ongoing eruption
is occurring as it could be centered anywhere from 449 feet below sea level at Ahyi's summit
to the seafloor at 9,800 feet depth.
Here is a quick list of every volcano which is currently erupting.
Also, here are some volcanoes showing signs of unrest which are not erupting but could
erupt in the near future.
Thanks for watching.
If you would like to request a specific topic please leave a comment below.
Additionally, if you wish to support this channel, consider becoming a patron on this
channel's patreon page!