This Week in Volcano News; Earthquake Swarm in Iceland, New Eruption in Russia


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As of September 11th, 2022, there are 49 volcanoes
actively erupting on the planet. One of these erupting volcanoes is Villarica
in Chile, which has been continuously erupting since December 2nd of 2014. While this volcano has produced some truly
large plinian eruptions in recent geologic times, including two caldera forming eruptions,
its recent eruptions have been much smaller. Villarica frequently has a lava lake present,
which aids in the generation of its frequent strombolian eruptions.

With this being said, here are this week's
major volcano related news stories. In Russia, a new explosive eruption occurred
at the Alaid volcano in the Kuril islands, sending a plume of ash to a height of 3,000
meters or 10,000 feet. Meanwhile, in New Zealand, a change in sensor
readings at the White Island volcano caused it's alert level to be raised. And, in Iceland, although there is no longer
an active eruption, there is an intense earthquake swarm ongoing to the north of the country. This earthquake swarm is occurring along a
known large strike slip fault zone which has generated quakes in the magnitude 6 range
in 1885, 1910, and 1976. For context, a strike slip fault is a boundary
that moves horizontally, with one famous example being the San Andreas fault. Known as the Grimsey Lineament, this fault
line connects with the northern volcanic zone to the south and a section of mid ocean ridge
to the north. Strike slip faults are common spots for volcanic
complexes, and this fault is no exception as they often act as a path of least resistance
for molten rock.

Part of the fault runs through or adjacent
to two volcanoes which have each produced eruptions since the country has been settled. One eruption occurred in 1372 to the northwest
of Grimsey while a second eruption occurred between December of 1867 and January of 1868
north of the island of Manareyjar. Its latest earthquake swarm began in the early
morning hours of September 8th, culminating in a magnitude 5.2 earthquake. Since then, more than 500 quakes have struck
along the fault line, largely being centered at between 1 and 17 kilometers in depth. While some people have speculated that these
quakes could be magmatic, I see no evidence as of yet that these are anything except tectonic
in origin. Aftershocks will continue in the upcoming
weeks albeit at a decreased rate unless another major earthquake occurs. Of the 49 volcanoes which are currently erupting,
two nations stand out as having the largest among this group. Indonesia has 7 actively erupting volcanoes,
while Russia has 6. During the last few months, two new eruptions
began in the Kuril island chain in far eastern Russia. Both of these eruptions began on the populated
Paramushir Island and were mildly explosive in nature.

Then, on September 10th, a third volcano known
as Alaid in close proximity to the erupting Ebeko and Chikurachki volcanoes but on a separate
island also unexpectedly erupted, sending a plume of ash to a height of 10,000 feet
or 3,000 meters. Alaid has historically produced some smaller
eruptions but it also has a record of highly explosive sub-plinian or plinian eruptions.

For example, its eruption in 1981 had a volcanic
explosivity index of a 4. However, such a large eruption is not to be
expected for the time being. What likely occurred was a medium sized phreatic
eruption with a probable volcanic explosivity index of a 1. Within New Zealand there are more than a dozen
active volcanoes. Of these, the second most active volcano since
1950 has been the scenic White Island volcano, with 24 distinct eruptions since then. These have largely consisted of phreatic eruptions
which are difficult to predict, meaning real-time monitoring of the volcano is crucial.

For several months the White Island volcano
has been at an alert level of 1 on the 0 to 5 scale. Then, due to a change in sensor readings,
its alert level was raised from 1 to 2 on September 7th of 2022. This change in alert level was made not due
to an increasing amount of volcanic activity but rather due to the fact that it had been
unsafe since 2019 to repair or replace decaying real-time equipment at the volcano due to
a persistent threat of another phreatic eruption.

On August 5th, the single remaining seismo-acoustic
station on the volcano stopped working. Since scientists no longer have sufficient
data to distinguish between activity which would be best suited via an alert level of
1 or an alert level of 2, it was raised to 2 as a precaution. 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, I would like to thank my new
patron Thomas Joseph Lydon for supporting this channel..


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