Smithsonian / USGS Weekly Volcanic Activity Report 23-29 November 2022

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4-4-4-4-4-4-4-4-4-4-4-4-4


From: "Kuhn, Sally" <KUHNS@xxxxxx>


Smithsonian / USGS Weekly Volcanic Activity Report

23-29 November 2022



Sally Kuhn Sennert - Weekly Report Editor (kuhns@xxxxxx)

URL: https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJKmv41rU$ 
<https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGEgrcwN8$>





New Activity/Unrest: Ahyi, Mariana Islands (USA)  | Cotopaxi, Ecuador  |
Etna, Sicily (Italy)  | Klyuchevskoy, Central Kamchatka (Russia)  | Mauna
Loa, Hawaiian Islands (USA)  | San Miguel, Eastern El Salvador



Ongoing Activity: Aira, Kyushu (Japan)  | Alaid, Kuril Islands (Russia)  |
Ebeko, Paramushir Island (Russia)  | Great Sitkin, Andreanof Islands (USA)
| Kerinci, Central Sumatra  | Kilauea, Hawaiian Islands (USA)  | Merapi,
Central Java  | Pavlof, Alaska Peninsula, Alaska  | Rincon de la Vieja,
Costa Rica  | Sangay, Ecuador  | Semeru, Eastern Java  | Semisopochnoi,
Aleutian Islands (USA)  | Sheveluch, Central Kamchatka (Russia)  |
Stromboli, Aeolian Islands (Italy)  | Suwanosejima, Ryukyu Islands (Japan)
| Villarrica, Central Chile  | Yasur, Vanuatu





The Weekly Volcanic Activity Report is a cooperative project between the
Smithsonian's Global Volcanism Program and the US Geological Survey's
Volcano Hazards Program. Updated by 2300 UTC every Wednesday, these reports
are preliminary and subject to change as events are studied in more detail.
This is not a comprehensive list of all of Earth's volcanoes erupting
during the week, but rather a summary of activity at volcanoes that meet
criteria discussed in detail in the "Criteria and Disclaimers" section.
Carefully reviewed, detailed reports about recent activity are published in
issues of the Bulletin of the Global Volcanism Network.



Note that many news agencies do not archive the articles they post on the
Internet, and therefore the links to some sources may not be active. To
obtain information about the cited articles that are no longer available on
the Internet contact the source.







New Activity/Unrest





Ahyi  | Mariana Islands (USA)  | 20.42°N, 145.03°E  | Summit elev. -75 m



Signs of unrest at Ahyi Seamount have been observed in satellite and remote
geophysical data, starting in mid-October. Hydroacoustic signals continued
to be observed but had declined in the previous few weeks. Discolored water
over the seamount was first visible on 18 November and persisted, possibly
from either degassing or an eruption. On 29 November the Aviation Color
Code was raised to Yellow (the second lowest level on a four-color scale)
and the Volcano Alert Level was raised to Advisory (the second lowest level
on a four-level scale).



Geologic Summary. Ahyi seamount is a large conical submarine volcano that
rises to within 75 m of the sea surface about 18 km SE of the island of
Farallon de Pajaros (Uracas) in the northern Marianas. Water discoloration
has been observed there, and in 1979 the crew of a fishing boat felt shocks
over the summit area of the seamount, followed by upwelling of
sulfur-bearing water. On 24-25 April 2001 an explosive eruption was
detected seismically by a station on Rangiroa Atoll, Tuamotu Archipelago.
The event was well constrained (+/- 15 km) at a location near the southern
base of Ahyi. An eruption in April-May 2014 was detected by NOAA divers,
hydroacoustic sensors, and seismic stations.



Source: US Geological Survey https://urldefense.com/v3/__https://www.usgs.gov/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJF-8uIkH$ 
<https://urldefense.com/v3/__https://www.usgs.gov/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoG--3gUVo$>





Cotopaxi  | Ecuador  | 0.677°S, 78.436°W  | Summit elev. 5911 m



On 22 November IG concluded that the minor ash emissions recorded at
Cotopaxi on 21 October were due to magma in the volcanoâ??s conduit, though
not from new magma entering the system after the 2015 eruption. An average
of one seismic event per day was recorded based on long-term seismic rates.
In the months prior to the 21 October event, the rate had gradually
increased to 1.5 events per day, though after the ash emission the rate
fell back to one event per day. Most of the seismicity was located beneath
the summit. Minor deformation was recorded during August-November, but it
could not be conclusively linked to the eruptive activity. Sulfur dioxide
emissions increased in October and gas-emission analysis indicated a
magmatic origin. Nearly continuous emissions of gas-and-steam had been
rising from the main crater since 21 October, as high as 2 km above the
rim. The heights of emissions averaged 200 m and were as high as 800 m in
2021.



At 1848 on 25 November the seismic network recorded a tremor signal
associated with a gas emission that drifted NNW. At approximately 0310 on
26 November a new episode of tremor was associated with a gas-and-ash
emissions that lasted for several hours. The plume drifted 85 km NNW,
passing over Quito (55 km N), and caused ashfall in El Pedregal (60 km N),
Tambillo (32 km NNW), Guamaní (42 km NNW), Amaguaña (33 km NNW),
Chillogallo (44 km NNW), Quitumbe (41 km NNW), Solanda (46 km NNW), Lloa
(48 km NNW), Conocoto (41 km N), Mercado Mayorista (45 km NNW), Villaflora
(47 km NNW), and Rumipamba (55 km N). Moderate levels of seismic tremor
were recorded until about 1050. Servicio Nacional de Gestión de Riesgos y
Emergencias (SNGRE) maintained the Alert Level at Yellow (the second lowest
level on a four-color scale).



Geologic Summary. The symmetrical, glacier-covered, Cotopaxi stratovolcano
is Ecuador's most well-known volcano and one of its most active. The
steep-sided cone is capped by nested summit craters, the largest of which
is about 550 x 800 m in diameter. Deep valleys scoured by lahars radiate
from the summit of the andesitic volcano, and large andesitic lava flows
extend to its base. The modern edifice has been constructed since a major
collapse sometime prior to about 5,000 years ago. Pyroclastic flows (often
confused in historical accounts with lava flows) have accompanied many
explosive eruptions, and lahars have frequently devastated adjacent
valleys. Strong eruptions took place in 1744, 1768, and 1877. Pyroclastic
flows descended all sides of the volcano in 1877, and lahars traveled more
than 100 km into the Pacific Ocean and western Amazon basin. Smaller
eruptions have been frequent since that time.



Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG)
https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJBYvTXXk$ 
<https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGR6Z8sew$>
;

Servicio Nacional de Gestión de Riesgos y Emergencias (SNGRE)
https://urldefense.com/v3/__https://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJDWAkFyi$ 
<https://urldefense.com/v3/__https://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGpzxqsow$>





Etna  | Sicily (Italy)  | 37.748°N, 14.999°E  | Summit elev. 3357 m



INGV reported that at about 1800 on 27 November a vent opened at the NE
base of Etnaâ??s SE Crater, at 2,800 m elevation, and produced a lava flow.
The flow slowly advanced a few hundred meters towards the Valle del Leone.
Tremor levels at the time the vent opened showed no variations from the
average trend recorded during the previous week, and no notable changes
were identified in deformation data. Effusive activity continued through 30
November, with additional small lava flows emplacing over the first one.
For a period of about an hour, beginning at 1700 on 29 November, tremor
amplitude increased and then peaked; the amplitude fluctuated between
medium and high values for a few hours afterwards. The source of the tremor
was in an area between the SE Crater and Bocca Nuova Crater, at elevations
of 2,000-2,600 m.



Geologic Summary. Mount Etna, towering above Catania on the island of
Sicily, has one of the world's longest documented records of volcanism,
dating back to 1500 BCE. Historical lava flows of basaltic composition
cover much of the surface of this massive volcano, whose edifice is the
highest and most voluminous in Italy. The Mongibello stratovolcano,
truncated by several small calderas, was constructed during the late
Pleistocene and Holocene over an older shield volcano. The most prominent
morphological feature of Etna is the Valle del Bove, a 5 x 10 km caldera
open to the east. Two styles of eruptive activity typically occur,
sometimes simultaneously. Persistent explosive eruptions, sometimes with
minor lava emissions, take place from one or more summit craters. Flank
vents, typically with higher effusion rates, are less frequently active and
originate from fissures that open progressively downward from near the
summit (usually accompanied by Strombolian eruptions at the upper end).
Cinder cones are commonly constructed over the vents of lower-flank lava
flows. Lava flows extend to the foot of the volcano on all sides and have
reached the sea over a broad area on the SE flank.



Source: Sezione di Catania - Osservatorio Etneo (INGV)
https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJBLvZRG_$ 
<https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGrqT2znw$>





Klyuchevskoy  | Central Kamchatka (Russia)  | 56.056°N, 160.642°E  | Summit
elev. 4754 m



On 24 November KVERT reported that the Strombolian eruption that had begun
at Klyuchevskoy on 16 November was ongoing. Lava fountaining at the summit
was visible and a thermal anomaly over the summit was identified in
satellite images during 17-20 and 24 November. The Aviation Color Code
remained at Yellow (the second lowest level on a four-color scale).



Geologic Summary. Klyuchevskoy (also spelled Kliuchevskoi) is Kamchatka's
highest and most active volcano. Since its origin about 6000 years ago, the
beautifully symmetrical, 4835-m-high basaltic stratovolcano has produced
frequent moderate-volume explosive and effusive eruptions without major
periods of inactivity. It rises above a saddle NE of sharp-peaked Kamen
volcano and lies SE of the broad Ushkovsky massif. More than 100 flank
eruptions have occurred during the past roughly 3000 years, with most
lateral craters and cones occurring along radial fissures between the
unconfined NE-to-SE flanks of the conical volcano between 500 m and 3600 m
elevation. The morphology of the 700-m-wide summit crater has been
frequently modified by historical eruptions, which have been recorded since
the late-17th century. Historical eruptions have originated primarily from
the summit crater, but have also included numerous major explosive and
effusive eruptions from flank craters.



Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJDFsiKuX$ 
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGXKQ-ZQw$>





Mauna Loa  | Hawaiian Islands (USA)  | 19.475°N, 155.608°W  | Summit elev.
4170 m



An eruption at Mauna Loa began at about 2330 on 27 November in
Mokuâ??aweoweo, the summit caldera, prompting HVO to raise the Aviation Color
Code to Red (the highest level on a four-color scale) and the Volcano Alert
Level to Warning (the highest level on a four-level scale). A thermal
anomaly and a plume of sulfur dioxide gas were identified in satellite
images at the onset of the eruption, according to NOAAâ??s National
Environmental Satellite, Data, and Information Service (NESDIS). Hawaiâ??i
Volcanoes National Park closed the summit area to visitors. Lava erupted
from a fissure in the caldera and by 0127 on 28 November lava had
overflowed the caldera walls. During an overflight at about 0630 scientists
confirmed that the eruption had moved from the summit to the Northeast Rift
Zone, where three fissures opened at a high elevation. The fissures fed
several lava flows that traveled N and NE; the flows were active in the
â??saddleâ?? area between Mauna Loa and Mauna Kea and were not threatening any
populated areas. Lava fountains along the fissures were as tall as 30-60 m,
though most were only a few meters tall. Lava flows from fissures 1 and 2
traveled downslope and stalled about 18 km from the Saddle Road; the two
fissures were inactive by 1330. Sulfur dioxide emissions were approximately
250,000 tonnes per day.



Fissure 3, at the lowest elevation of the NE fissures, issued the longest
lava flows. Lava flows crossed the Mauna Loa Weather Observatory Road at
about 2000 on 28 November; by 0700 on 29 November the flow front was about
10 km from the Saddle Road. Lava fountains at Fissure 3 were 25 m high in
the morning on 29 November but had grown to 40-50 m tall in the afternoon.
Fissure 4, downslope of Fissure 3, opened at about 1930 and produced lava
fountains that rose 5-10 m high. There was no activity in the summit
caldera, nor along the Southwest Rift Zone. Gas plumes from the activity
drifted N.



Geologic Summary. Massive Mauna Loa is a basaltic shield volcano that rises
almost 9 km from the ocean floor to form the world's largest Holocene
volcano. Flank eruptions typically occur from the lengthy NE and SW rift
zones, and from the Moku'aweoweo summit is caldera, which is within an
older and larger 6 x 8 km caldera. Two of the youngest large debris
avalanches documented in Hawaii traveled nearly 100 km from Mauna Loa; the
second of the Alika avalanches was emplaced about 105,000 years ago (Moore
et al., 1989). Almost 90% of the surface of the volcano is covered by lavas
less than 4,000 years old (Lockwood and Lipman, 1987). Beginning about
1,500 years ago, a series of voluminous overflows from a summit lava lake
covered about 25% of the volcano's surface. Over the last 750 years, from
shortly after the formation of Moku'aweoweo caldera until the present, an
additional 25% of the volcano has been covered with lava flows, mainly from
summit and NW rift zone vents.



Sources: US Geological Survey Hawaiian Volcano Observatory (HVO)
https://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJFSDw_Pv$ 
<https://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoG8wt1mrs$>
;

National Environmental Satellite, Data, and Information Service (NESDIS)
https://urldefense.com/v3/__https://www.nesdis.noaa.gov/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJFg1egoZ$ 
<https://urldefense.com/v3/__https://www.nesdis.noaa.gov/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGzFswnN0$>





San Miguel  | Eastern El Salvador  | 13.434°N, 88.269°W  | Summit elev.
2130 m



MARN reported that the eruption at San Miguel continued during 23-28
November. Daily phreatic explosions produced gas, steam, and ash emissions
that generally rose around 500 m above the crater rim. There were a total
of 188 events recorded by 28 November, with a daily average of 13. The
explosions were more energetic mid-week; explosions at 1302 and 1642 on 26
November and 0718 and 0802 on 27 November ejected hot rocks onto the flanks
and produced eruption plumes that rose as high as 1.1 km above the summit.
A cow was killed by hot ballistics during the morning of 27 November,
according to a news article. El Director General de Protección Civil issued
a Green Alert for the municipalities of Chinameca, San Rafael Oriente, and
San Jorge, and warned the public to stay 3 km away from the volcano. The
notice recommended that those living within a 3-6 km radius should identify
evacuation routes and to take preparation measures as guided by the Sistema
Nacional de Protección Civil.



Sulfur dioxide emissions generally averaged 283 tons per day during 26-27
November, below the baseline of 300 tons per day. Specific measurements
during explosive events revealed that the emissions were sometimes as high
as 1,200 tons per day. MARN warned the public to stay 2 km away from the
volcano, and for those living within a 2-5 km radius to identify evacuation
routes and to take preparation measures as guided by the Sistema Nacional
de Protección Civil.



Geologic Summary. The symmetrical cone of San Miguel, one of the most
active volcanoes in El Salvador, rises from near sea level to form one of
the country's most prominent landmarks. A broad, deep, crater complex that
has been frequently modified by eruptions recorded since the early 16th
century caps the truncated unvegetated summit, also known locally as
Chaparrastique. Flanks eruptions of the basaltic-andesitic volcano have
produced many lava flows, including several during the 17th-19th centuries
that extended to the N, NE, and SE. The SE-flank flows are the largest and
form broad, sparsely vegetated lava fields crossed by highways and a
railroad skirting the base of the volcano. Flank vent locations have
migrated higher on the edifice during historical time, and the most recent
activity has consisted of minor ash eruptions from the summit crater.



Sources: Ministerio de Medio Ambiente y Recursos Naturales (MARN)
https://urldefense.com/v3/__https://marn.gob.sv/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJAg2c-s9$ 
<https://urldefense.com/v3/__https://marn.gob.sv/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGBcXZmk0$>
;

ASAP Televisión
https://urldefense.com/v3/__https://asap-tv.com/2022/11/27/vaca-muere-impacto-roca-lanzada-volcan-san-miguel/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJLnr9I_y$ 
<https://urldefense.com/v3/__https://asap-tv.com/2022/11/27/vaca-muere-impacto-roca-lanzada-volcan-san-miguel/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGqHl4uTs$>
;

Protección Civil de El Salvador https://urldefense.com/v3/__https://www.proteccioncivil.gob.sv/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJBUc5Asb$ 
<https://urldefense.com/v3/__https://www.proteccioncivil.gob.sv/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGYoO_oaY$>





Ongoing Activity





Aira  | Kyushu (Japan)  | 31.593°N, 130.657°E  | Summit elev. 1117 m



JMA reported ongoing eruptive activity at Minamidake Crater (at Aira
Calderaâ??s Sakurajima volcano) and nighttime crater incandescence during
21-28 November. Sulfur dioxide emissions were 700 tons per day on 21
November. An explosion on 21 November produced an ash plume that rose as
high as 2.2 km above the crater rim and ejected large blocks as far as 500
m from the vent. Small eruptive events were recorded during 25-28 November.
The Alert Level remained at 3 (on a 5-level scale), and residents were
warned to stay 2 km away from the crater.



Geologic Summary. The Aira caldera in the northern half of Kagoshima Bay
contains the post-caldera Sakurajima volcano, one of Japan's most active.
Eruption of the voluminous Ito pyroclastic flow accompanied formation of
the 17 x 23 km caldera about 22,000 years ago. The smaller Wakamiko caldera
was formed during the early Holocene in the NE corner of the Aira caldera,
along with several post-caldera cones. The construction of Sakurajima began
about 13,000 years ago on the southern rim of Aira caldera and built an
island that was finally joined to the Osumi Peninsula during the major
explosive and effusive eruption of 1914. Activity at the Kitadake summit
cone ended about 4850 years ago, after which eruptions took place at
Minamidake. Frequent historical eruptions, recorded since the 8th century,
have deposited ash on Kagoshima, one of Kyushu's largest cities, located
across Kagoshima Bay only 8 km from the summit. The largest historical
eruption took place during 1471-76.



Source: Japan Meteorological Agency (JMA) https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJFjIULuW$ 
<https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGZ6q2gUg$>





Alaid  | Kuril Islands (Russia)  | 50.861°N, 155.565°E  | Summit elev. 2285
m



KVERT lowered the Aviation Color Code for Alaid to Green (the lowest level
on a four-color scale) on 24 November noting that activity had been
gradually decreasing since the last ash plume was recorded on 26 October.
The temperature of the thermal anomaly began decreasing on 29 October and
reached background levels by 20 November. At 1025 on 26 November (local
time) ash plumes from explosions were visible in satellite images drifting
38 km SE at altitudes of 4.5-4.7 km 14,800-15,400 ft) a.s.l. The Aviation
Color Code was raised to Orange. Explosions continued through the day; by
1521 (local time) ash plumes were rising to 3.5 km (11,500 ft) a.s.l. and
ash plumes had drifted as far as 220 km SE. Dates are based on UTC times;
specific events are in local time where noted.



Geologic Summary. The highest and northernmost volcano of the Kuril
Islands, Alaid is a symmetrical stratovolcano when viewed from the north,
but has a 1.5-km-wide summit crater that is breached open to the south.
This basaltic to basaltic-andesite volcano is the northernmost of a chain
constructed west of the main Kuril archipelago. Numerous pyroclastic cones
are present the lower flanks, particularly on the NW and SE sides,
including an offshore cone formed during the 1933-34 eruption. Strong
explosive eruptions have occurred from the summit crater beginning in the
18th century. Reports of eruptions in 1770, 1789, 1821, 1829, 1843, 1848,
and 1858 were considered incorrect by Gorshkov (1970). Explosive eruptions
in 1790 and 1981 were among the largest reported in the Kuril Islands.



Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJDFsiKuX$ 
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGXKQ-ZQw$>





Ebeko  | Paramushir Island (Russia)  | 50.686°N, 156.014°E  | Summit elev.
1103 m



KVERT reported that a thermal anomaly over Ebeko was identified in
satellite images on 20 November. Weather clouds prevented views of the
volcano on the other days during 17-24 November. The Aviation Color Code
remained at Orange (the second highest level on a four-color scale). Dates
are based on UTC times; specific events are in local time where noted.



Geologic Summary. The flat-topped summit of the central cone of Ebeko
volcano, one of the most active in the Kuril Islands, occupies the northern
end of Paramushir Island. Three summit craters located along a SSW-NNE line
form Ebeko volcano proper, at the northern end of a complex of five
volcanic cones. Blocky lava flows extend west from Ebeko and SE from the
neighboring Nezametnyi cone. The eastern part of the southern crater
contains strong solfataras and a large boiling spring. The central crater
is filled by a lake about 20 m deep whose shores are lined with steaming
solfataras; the northern crater lies across a narrow, low barrier from the
central crater and contains a small, cold crescentic lake. Historical
activity, recorded since the late-18th century, has been restricted to
small-to-moderate explosive eruptions from the summit craters. Intense
fumarolic activity occurs in the summit craters, on the outer flanks of the
cone, and in lateral explosion craters.



Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJDFsiKuX$ 
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGXKQ-ZQw$>





Great Sitkin  | Andreanof Islands (USA)  | 52.076°N, 176.13°W  | Summit
elev. 1740 m



AVO reported that slow lava effusion continued at Great Sitkin during 23-29
November and the flow field continued to grow. Elevated surface
temperatures were identified in satellite images during 27-29 November. The
Volcano Alert Level remained at Watch (the second highest level on a
four-level scale) and the Aviation Color Code remained at Orange (the
second highest level on a four-color scale).



Geologic Summary. The Great Sitkin volcano forms much of the northern side
of Great Sitkin Island. A younger parasitic volcano capped by a small, 0.8
x 1.2 km ice-filled summit caldera was constructed within a large
late-Pleistocene or early Holocene scarp formed by massive edifice failure
that truncated an ancestral volcano and produced a submarine debris
avalanche. Deposits from this and an older debris avalanche from a source
to the south cover a broad area of the ocean floor north of the volcano.
The summit lies along the eastern rim of the younger collapse scarp.
Deposits from an earlier caldera-forming eruption of unknown age cover the
flanks of the island to a depth up to 6 m. The small younger caldera was
partially filled by lava domes emplaced in 1945 and 1974, and five small
older flank lava domes, two of which lie on the coastline, were constructed
along northwest- and NNW-trending lines. Hot springs, mud pots, and
fumaroles occur near the head of Big Fox Creek, south of the volcano.
Historical eruptions have been recorded since the late-19th century.



Source: US Geological Survey Alaska Volcano Observatory (AVO)
https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJAbMDTL9$ 
<https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGUTNbpjY$>





Kerinci  | Central Sumatra  | 1.697°S, 101.264°E  | Summit elev. 3800 m



PVMBG reported that white steam-and-gas plumes rose as high as 150 m above
Kerinciâ??s summit and drifted NE during 25-26 November. Gray plumes of
variable densities rose 100-500 m above the summit and drifted NE, E, and
NW. At 0830 on 27 November a gray ash plume rose about 400 m above the
summit and drifted E. The Aviation Color Code remained at Orange (the
second highest level on a four-color scale). The Alert Level remained at 2
(on a scale of 1-4), and the public was warned to remain outside of the
3-km exclusion zone.



Geologic Summary. Gunung Kerinci in central Sumatra forms Indonesia's
highest volcano and is one of the most active in Sumatra. It is capped by
an unvegetated young summit cone that was constructed NE of an older crater
remnant. There is a deep 600-m-wide summit crater often partially filled by
a small crater lake that lies on the NE crater floor, opposite the SW-rim
summit. The massive 13 x 25 km wide volcano towers 2400-3300 m above
surrounding plains and is elongated in a N-S direction. Frequently active,
Kerinci has been the source of numerous moderate explosive eruptions since
its first recorded eruption in 1838.



Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known
as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJGOY7WSB$ 
<https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoG44pFKzk$>





Kilauea  | Hawaiian Islands (USA)  | 19.421°N, 155.287°W  | Summit elev.
1222 m



HVO reported that lava continued to effuse from a vent in the lower W wall
of Kilaueaâ??s Halema`uma`u Crater during 23-29 November entering the lava
lake and flowing onto the crater floor. The active part of the lake
remained at a steady level all week. The Volcano Alert Level remained at
Watch (the second highest level on a four-level scale) and the Aviation
Color Code remained at Orange (the second highest level on a four-color
scale).



Geologic Summary. Kilauea overlaps the E flank of the massive Mauna Loa
shield volcano in the island of Hawaii. Eruptions are prominent in
Polynesian legends; written documentation since 1820 records frequent
summit and flank lava flow eruptions interspersed with periods of long-term
lava lake activity at Halemaumau crater in the summit caldera until 1924.
The 3 x 5 km caldera was formed in several stages about 1,500 years ago and
during the 18th century; eruptions have also originated from the lengthy
East and Southwest rift zones, which extend to the ocean in both
directions. About 90% of the surface of the basaltic shield volcano is
formed of lava flows less than about 1,100 years old; 70% of the surface is
younger than 600 years. The long-term eruption from the East rift zone
between 1983 and 2018 produced lava flows covering more than 100 km2,
destroyed hundreds of houses, and added new coastline.



Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
https://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJFSDw_Pv$ 
<https://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoG8wt1mrs$>





Merapi  | Central Java  | 7.54°S, 110.446°E  | Summit elev. 2910 m



BPPTKG reported that the eruption at Merapi continued during 18-24 November
and seismicity remained at high levels. The SW lava dome produced 13 lava
avalanches that traveled as far as 1.6 km down the SW flank (upstream in
the Kali Bebeng drainage). No significant morphological changes to the
central and SW lava domes were evident. According to the Darwin VAAC an ash
plume rose to 4.6 km (15,000 ft) a.s.l. and drifted SW on 25 November. The
Alert Level remained at 3 (on a scale of 1-4), and the public was warned to
stay 3-7 km away from the summit based on location.



Geologic Summary. Merapi, one of Indonesia's most active volcanoes, lies in
one of the world's most densely populated areas and dominates the landscape
immediately north of the major city of Yogyakarta. It is the youngest and
southernmost of a volcanic chain extending NNW to Ungaran volcano. Growth
of Old Merapi during the Pleistocene ended with major edifice collapse
perhaps about 2,000 years ago, leaving a large arcuate scarp cutting the
eroded older Batulawang volcano. Subsequent growth of the steep-sided Young
Merapi edifice, its upper part unvegetated due to frequent activity, began
SW of the earlier collapse scarp. Pyroclastic flows and lahars accompanying
growth and collapse of the steep-sided active summit lava dome have
devastated cultivated lands on the western-to-southern flanks and caused
many fatalities.



Sources: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi
(BPPTKG) https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJAdXij40$ 
<https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGb0UXwE4$>
;

Darwin Volcanic Ash Advisory Centre (VAAC)
https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJAad2ckZ$ 
<https://urldefense.com/v3/__http://www.bom.gov.au/aviation/volcanic-ash/darwin-va-advisory.shtml__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoG1ArqMuQ$>





Pavlof  | Alaska Peninsula, Alaska  | 55.417°N, 161.894°W  | Summit elev.
2493 m



AVO reported that a minor eruption at a vent on Pavlofâ??s upper E flank was
ongoing during 23-29 November and nearly continuous seismic tremor was
recorded. Vent incandescence was visible in webcam images on most days,
suggesting ongoing lava effusion. Elevated surface temperatures were
occasionally identified in satellite images. Minor ash emissions were
observed in webcam images during 26-27 November. A seismic signal at 1748
on 28 November indicated a flowage event. Webcam images from 29 November
confirmed that a flowage event had occurred, and a resulting gas cloud
possibly containing ash rose as high as 6.1 km (20,000 ft) a.s.l. The
Volcano Alert Level remained at Watch (the second highest level on a
four-level scale) and the Aviation Color Code remained at Orange (the
second highest level on a four-color scale).



Geologic Summary. The most active volcano of the Aleutian arc, Pavlof is a
2519-m-high Holocene stratovolcano that was constructed along a line of
vents extending NE from the Emmons Lake caldera. Pavlof and its twin
volcano to the NE, 2142-m-high Pavlof Sister, form a dramatic pair of
symmetrical, glacier-covered stratovolcanoes that tower above Pavlof and
Volcano bays. A third cone, Little Pavlof, is a smaller volcano on the SW
flank of Pavlof volcano, near the rim of Emmons Lake caldera. Unlike Pavlof
Sister, Pavlof has been frequently active in historical time, typically
producing Strombolian to Vulcanian explosive eruptions from the summit
vents and occasional lava flows. The active vents lie near the summit on
the north and east sides. The largest historical eruption took place in
1911, at the end of a 5-year-long eruptive episode, when a fissure opened
on the N flank, ejecting large blocks and issuing lava flows.



Source: US Geological Survey Alaska Volcano Observatory (AVO)
https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJAbMDTL9$ 
<https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGUTNbpjY$>





Rincon de la Vieja  | Costa Rica  | 10.83°N, 85.324°W  | Summit elev. 1916 m



OVSICORI-UNA reported continuing eruptive activity at Rincón de la Vieja
characterized by occasional small phreatic explosions; five were recorded
during 19-25 November. A notable variability in sulfur dioxide emissions
was first observed on 18 November and continued through the week, with a
peak measurement as high as 1,500 tons per day. A phreatic explosion at
1432 on 25 November produced a steam-rich plume that rose 2 km and drifted
SW.



Geologic Summary. Rincón de la Vieja, the largest volcano in NW Costa Rica,
is a remote volcanic complex in the Guanacaste Range. The volcano consists
of an elongated, arcuate NW-SE-trending ridge constructed within the
15-km-wide early Pleistocene Guachipelín caldera, whose rim is exposed on
the south side. Sometimes known as the "Colossus of Guanacaste," it has an
estimated volume of 130 km3 and contains at least nine major eruptive
centers. Activity has migrated to the SE, where the youngest-looking
craters are located. The twin cone of Santa María volcano, the highest peak
of the complex, is located at the eastern end of a smaller, 5-km-wide
caldera and has a 500-m-wide crater. A Plinian eruption producing the 0.25
km3 Río Blanca tephra about 3,500 years ago was the last major magmatic
eruption. All subsequent eruptions, including numerous historical eruptions
possibly dating back to the 16th century, have been from the prominent
active crater containing a 500-m-wide acid lake located ENE of Von Seebach
crater.



Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad
Nacional (OVSICORI-UNA) https://urldefense.com/v3/__http://www.ovsicori.una.ac.cr/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJAQYzYrF$ 
<https://urldefense.com/v3/__http://www.ovsicori.una.ac.cr/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGqWdObqY$>





Sangay  | Ecuador  | 2.005°S, 78.341°W  | Summit elev. 5286 m



IG reported a high level of activity at Sangay during 22-29 November, which
included daily explosions, volcanic tremor, and gas-and-steam emissions.
The daily count of explosions ranged from 920-1,320, though seismic data
transmission was sometimes interrupted. Daily ash-and-gas plumes were
identified in either or both IG webcam images and satellite images
according to the Washington VAAC. Plumes rose as high as 2.1 km above the
volcano and drifted in various directions. Sulfur dioxide emissions were
measured daily and ranged from 491.2 tons per day to 3,693.5 tons per day.
During 22-29 November crater incandescence was visible at night and early
mornings. Pyroclastic flows descended the flanks during 24-29 November.
Lava flows, incandescent blocks, and incandescent material descended the SE
flank during 25-29 November.



Geologic Summary. The isolated Sangay volcano, located east of the Andean
crest, is the southernmost of Ecuador's volcanoes and its most active. The
steep-sided, glacier-covered, dominantly andesitic volcano grew within the
open calderas of two previous edifices which were destroyed by collapse to
the east, producing large debris avalanches that reached the Amazonian
lowlands. The modern edifice dates back to at least 14,000 years ago. It
towers above the tropical jungle on the east side; on the other sides flat
plains of ash have been eroded by heavy rains into steep-walled canyons up
to 600 m deep. The earliest report of an eruption was in 1628. Almost
continuous eruptions were reported from 1728 until 1916, and again from
1934 to the present. The almost constant activity has caused frequent
changes to the morphology of the summit crater complex.



Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJBYvTXXk$ 
<https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGR6Z8sew$>





Semeru  | Eastern Java  | 8.108°S, 112.922°E  | Summit elev. 3657 m



PVMBG reported that the eruption at Semeru continued during 23-29 November.
Daily explosions at the summit produced ash plumes that varied in color and
density, which generally rose 500-700 m above the summit and drifted in
various directions. A dense gray ash plume at 0002 on 23 November rose 700
m and drifted SE and S, at 0507 and 0540 on 24 November white-to-gray and
dense gray ash plumes, respectively, rose 500 m and drifted N, at 0702 on
25 November a dense gray ash plume rose 500 m and drifted NE, at 0444 on 26
November an ash plume rose 700 m and drifted S, at 0552 on 27 November a
white-to-gray ash plume rose 500 m and drifted S, at 0556 on 28 November a
dense gray ash plume rose 500 m and drifted N, that same day at 0611 a
dense gray ash plume rose possibly higher than 1 km, and at 0509 on 29
November a white-and-gray ash plume rose 600 m and drifted N. The Alert
Level remained at 3 (on a scale of 1-4). The public was warned to stay at
least 5 km away from the summit, and 500 m from Kobokan drainages within 17
km of the summit, along with other drainages originating on Semeru,
including the Bang, Kembar, and Sat, due to lahar, avalanche, and
pyroclastic flow hazards.



Geologic Summary. Semeru, the highest volcano on Java, and one of its most
active, lies at the southern end of a volcanic massif extending north to
the Tengger caldera. The steep-sided volcano, also referred to as Mahameru
(Great Mountain), rises above coastal plains to the south. Gunung Semeru
was constructed south of the overlapping Ajek-ajek and Jambangan calderas.
A line of lake-filled maars was constructed along a N-S trend cutting
through the summit, and cinder cones and lava domes occupy the eastern and
NE flanks. Summit topography is complicated by the shifting of craters from
NW to SE. Frequent 19th and 20th century eruptions were dominated by
small-to-moderate explosions from the summit crater, with occasional lava
flows and larger explosive eruptions accompanied by pyroclastic flows that
have reached the lower flanks of the volcano.



Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known
as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJGOY7WSB$ 
<https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoG44pFKzk$>





Semisopochnoi  | Aleutian Islands (USA)  | 51.93°N, 179.58°E  | Summit
elev. 1221 m



On 23 November AVO lowered the Aviation Color Code for Semisopochnoi 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)
noting that no ash emissions or explosive activity had been detected since
7 November. Seismicity had decreased, though remained at elevated levels.
Steam emissions from the active vent in the N crater of Mount Cerberus
persisted.



Geologic Summary. Semisopochnoi, the largest subaerial volcano of the
western Aleutians, is 20 km wide at sea level and contains an 8-km-wide
caldera. It formed as a result of collapse of a low-angle, dominantly
basaltic volcano following the eruption of a large volume of dacitic
pumice. The high point of the island is Anvil Peak, a double-peaked
late-Pleistocene cone that forms much of the island's northern part. The
three-peaked Mount Cerberus was constructed within the caldera during the
Holocene. Each of the peaks contains a summit crater; lava flows on the N
flank of Cerberus appear younger than those on the south side. Other
post-caldera volcanoes include the symmetrical Sugarloaf Peak SSE of the
caldera and Lakeshore Cone, a small cinder cone at the edge of Fenner Lake
in the NE part of the caldera. Most documented eruptions have originated
from Cerberus, although Coats (1950) considered that both Sugarloaf and
Lakeshore Cone could have been recently active.



Source: US Geological Survey Alaska Volcano Observatory (AVO)
https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJAbMDTL9$ 
<https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGUTNbpjY$>





Sheveluch  | Central Kamchatka (Russia)  | 56.653°N, 161.36°E  | Summit
elev. 3283 m



KVERT reported that the ongoing eruption at Sheveluch during 17-24 November
was generally characterized by explosions, hot avalanches, lava-dome
extrusion, and strong fumarolic activity. A daily thermal anomaly was
identified in satellite images. Collapses generated hot avalanches and ash
plumes that drifted 80 km E during 17-18 and 20 November. The Aviation
Color Code remained at Orange (the second highest level on a four-color
scale). Dates are based on UTC times; specific events are in local time
where noted.



Geologic Summary. The high, isolated massif of Sheveluch volcano (also
spelled Shiveluch) rises above the lowlands NNE of the Kliuchevskaya
volcano group. The 1,300 km3 andesitic volcano is one of Kamchatka's
largest and most active volcanic structures, with at least 60 large
eruptions during the Holocene. The summit of roughly 65,000-year-old Stary
Shiveluch is truncated by a broad 9-km-wide late-Pleistocene caldera
breached to the south. Many lava domes occur on its outer flanks. The
Molodoy Shiveluch lava dome complex was constructed during the Holocene
within the large open caldera; Holocene lava dome extrusion also took place
on the flanks of Stary Shiveluch. Widespread tephra layers from these
eruptions have provided valuable time markers for dating volcanic events in
Kamchatka. Frequent collapses of dome complexes, most recently in 1964,
have produced debris avalanches whose deposits cover much of the floor of
the breached caldera.



Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJDFsiKuX$ 
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGXKQ-ZQw$>





Stromboli  | Aeolian Islands (Italy)  | 38.789°N, 15.213°E  | Summit elev.
924 m



INGV reported that during 21-27 November activity at Stromboli was
characterized by ongoing explosions at three vents in Area N (North Crater
area) and two vents in Area C-S (South-Central Crater area); weather
conditions prevented visual confirmation of activity during 21-23 November.
Low-intensity explosions from the N1 vent (Area N) ejected course material
(bombs and lapilli) less than 80 m high at a rate of 3-7 explosions per
hour. Spattering and occasional low-intensity explosive activity was
visible at the N2 vent (Area N). Explosions from at least two vents in S2
(Area C-S) ejected ash and coarse material over 250 m above the vent at a
rate of 6 events per hour.



Geologic Summary. Spectacular incandescent nighttime explosions at
Stromboli have long attracted visitors to the "Lighthouse of the
Mediterranean" in the NE Aeolian Islands. This volcano has lent its name to
the frequent mild explosive activity that has characterized its eruptions
throughout much of historical time. The small island is the emergent summit
of a volcano that grew in two main eruptive cycles, the last of which
formed the western portion of the island. The Neostromboli eruptive period
took place between about 13,000 and 5,000 years ago. The active summit
vents are located at the head of the Sciara del Fuoco, a prominent scarp
that formed about 5,000 years ago due to a series of slope failures which
extends to below sea level. The modern volcano has been constructed within
this scarp, which funnels pyroclastic ejecta and lava flows to the NW.
Essentially continuous mild Strombolian explosions, sometimes accompanied
by lava flows, have been recorded for more than a millennium.



Source: Sezione di Catania - Osservatorio Etneo (INGV)
https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJBLvZRG_$ 
<https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGrqT2znw$>





Suwanosejima  | Ryukyu Islands (Japan)  | 29.638°N, 129.714°E  | Summit
elev. 796 m



JMA reported that the eruption at Suwanosejima's Ontake Crater continued
during 21-28 November and crater incandescence was visible nightly.
Eruption plumes rose as high as 1.3 km above the crater rim and blocks were
ejected as far as 300 m from the vent. Ashfall was occasionally reported in
Toshima village (3.5 km SSW). The Alert Level remained at 3 (on a 5-level
scale), and residents were warned to stay 2 km away from the crater.



Geologic Summary. The 8-km-long island of Suwanosejima in the northern
Ryukyu Islands consists of an andesitic stratovolcano with two historically
active summit craters. The summit is truncated by a large breached crater
extending to the sea on the east flank that was formed by edifice collapse.
One of Japan's most frequently active volcanoes, it was in a state of
intermittent Strombolian activity from Otake, the NE summit crater, between
1949 and 1996, after which periods of inactivity lengthened. The largest
recorded eruption took place in 1813-14, when thick scoria deposits
blanketed residential areas, and the SW crater produced two lava flows that
reached the western coast. At the end of the eruption the summit of Otake
collapsed, forming a large debris avalanche and creating the open Sakuchi
caldera, which extends to the eastern coast. The island remained
uninhabited for about 70 years after the 1813-1814 eruption. Lava flows
reached the eastern coast of the island in 1884. Only about 50 people live
on the island.



Source: Japan Meteorological Agency (JMA) https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJFjIULuW$ 
<https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGZ6q2gUg$>





Villarrica  | Central Chile  | 39.42°S, 71.93°W  | Summit elev. 2847 m



POVI reported minor gas-and-steam emissions at Villarrica on 24 November;
one circular emission (â??vortex ringâ??) was also visible. During an
overflight on 25 November, SERNAGEOMIN scientists observed the small cone
on the crater floor with an incandescent lava lake at its center. The lake
temperature was 1,043 degrees Celsius. The Alert Level remained at Yellow
(the second lowest level on a four-color scale) and the public was warned
that material could be ejected within 500 m of the crater. ONEMI remained
the Alert Level Yellow (the middle level on a three-color scale) for the
municipalities of Villarrica, Pucón (16 km N), Curarrehue, and the commune
of Panguipulli.



Geologic Summary. Glacier-clad Villarrica, one of Chile's most active
volcanoes, rises above the lake and town of the same name. It is the
westernmost of three large stratovolcanoes that trend perpendicular to the
Andean chain. A 6-km-wide caldera formed during the late Pleistocene. A
2-km-wide caldera that formed about 3500 years ago is located at the base
of the presently active, dominantly basaltic to basaltic-andesitic cone at
the NW margin of the Pleistocene caldera. More than 30 scoria cones and
fissure vents dot the flanks. Plinian eruptions and pyroclastic flows that
have extended up to 20 km from the volcano were produced during the
Holocene. Lava flows up to 18 km long have issued from summit and flank
vents. Historical eruptions, documented since 1558, have consisted largely
of mild-to-moderate explosive activity with occasional lava effusion.
Glaciers cover 40 km2 of the volcano, and lahars have damaged towns on its
flanks.



Sources: Proyecto Observación Villarrica Internet (POVI) https://urldefense.com/v3/__http://www.povi.cl/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJIeuuQZV$ 
<https://urldefense.com/v3/__http://www.povi.cl/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGZZ2Kd8I$>
;

Servicio Nacional de Geología y Minería (SERNAGEOMIN)
https://urldefense.com/v3/__http://www.sernageomin.cl/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJAKV6CRN$ 
<https://urldefense.com/v3/__http://www.sernageomin.cl/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGacPk12U$>
;

Oficina Nacional de Emergencia-Ministerio del Interior (ONEMI)
https://urldefense.com/v3/__http://www.onemi.cl/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJNCvMhZ8$ 
<https://urldefense.com/v3/__http://www.onemi.cl/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoG__KFeik$>





Yasur  | Vanuatu  | 19.532°S, 169.447°E  | Summit elev. 361 m



On 24 November Vanuatu Meteorology and Geohazards Department (VMGD)
reported that activity at Yasur continued at a high level of â??major
unrest,â?? as defined by the Alert Level 2 status (the middle level on a
scale of 0-4). Recent observations confirmed continuing low-to-moderate
explosions that ejected bombs within the crater and produced ash, gas, and
steam emissions. The public was reminded to not enter the restricted area
within 600 m around the cone, defined by Danger Zone A on the hazard map.



Geologic Summary. Yasur has exhibited essentially continuous Strombolian
and Vulcanian activity at least since Captain Cook observed ash eruptions
in 1774. This style of activity may have continued for the past 800 years.
Located at the SE tip of Tanna Island in Vanuatu, this pyroclastic cone has
a nearly circular, 400-m-wide summit crater. The active cone is largely
contained within the small Yenkahe caldera, and is the youngest of a group
of Holocene volcanic centers constructed over the down-dropped NE flank of
the Pleistocene Tukosmeru volcano. The Yenkahe horst is located within the
Siwi ring fracture, a 4-km-wide open feature associated with eruption of
the andesitic Siwi pyroclastic sequence. Active tectonism along the Yenkahe
horst accompanying eruptions has raised Port Resolution harbor more than 20
m during the past century.



Source: Vanuatu Meteorology and Geo-Hazards Department (VMGD)
https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!blhsa6zPIXONYvRCAVyQCOIt5De0wPjK6NpSiNoXX03uJGZ_N1a4FKIqykkNvngnIdPC6PRlJOqTLpIG$ 
<https://urldefense.com/v3/__http://www.geohazards.gov.vu/__;!!IKRxdwAv5BmarQ!bcwP9vMaA1yuT6KLM_JM6Fw8XutkItONFYCPWeQUMGqBrFCKwd-n-9ZWmn_mEatPPBoGM8Ug4rY$>



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End of Volcano Digest - 29 Nov 2022 to 30 Nov 2022 (#2022-124)
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