Smithsonian / USGS Weekly Volcanic Activity Report 24-30 July 2024

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5-5-5-5-5-5-5-5-5-5-5-5-5-5


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


Smithsonian / USGS Weekly Volcanic Activity Report

24-30 July 2024



Sally Sennert - Weekly Report Editor (kuhns@xxxxxx)

URL: https://volcano.si.edu/reports_weekly.cfm
<https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkRSSn657A$>





New Activity/Unrest: Bezymianny, Central Kamchatka (Russia)  | Etna, Sicily
(Italy)  | Karymsky, Eastern Kamchatka (Russia)  | Katla, Iceland  |
Kelimutu, Flores Island  | Kilauea, Hawaiian Islands (USA)  | Nyamulagira,
DR Congo  | Whakaari/White Island, North Island (New Zealand)  |
Yellowstone, Eastern Snake River Plain



Ongoing Activity: Aira, Kyushu (Japan)  | Dukono, Halmahera  | Ebeko,
Paramushir Island (Russia)  | Great Sitkin, Andreanof Islands (USA)  | Ibu,
Halmahera  | Lewotobi, Flores Island  | Merapi, Central Java  | Reventador,
Ecuador  | Sabancaya, Peru  | Sangay, Ecuador  | Sheveluch, Central
Kamchatka (Russia)  | Suwanosejima, Ryukyu Islands (Japan)  | Ubinas, Peru
| Villarrica, Central Chile





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





Bezymianny  | Central Kamchatka (Russia)  | 55.972°N, 160.595°E  | Summit
elev. 2882 m



KVERT reported that activity at Bezymianny increased on 21 July and then
escalated on 24 July. Lava-dome extrusion significantly increased on 21
July, causing collapses of the E part of the lava dome and subsequent hot
avalanches of material. Activity continued and on 22 July the Aviation
Color Code was raised to Orange (the third level on a four-color scale).
Extrusion and collapses continued through 24 July with ash plumes
continuing to rise 2-3 km a.s.l. and drift at least 70 km SW. A strong
explosive eruption began at 1510 on 24 July, prompting KVERT to raise the
Aviation Color Code to Red at 2002. The explosions produced a large ash
plume that initially rose to 9.6 km (31,500 ft) a.s.l. and then to 12 km
(39,400 ft) a.s.l.; the plume drifted 300 km ESE. Pyroclastic flows
descended the flanks. By 0035 on 25 July the explosive phase had ended so
the Aviation Color Code was lowered to Orange. Effusion at the lava dome
continued and viscous lava extruded onto the domeâ??s flanks. The activity
was accompanied by notable steam-and-gas emissions and the descent of hot
avalanches. Ash clouds generated on 24 July were visible in satellite
images drifting 2,500 km SE until 25 July and 1,800 km SW until 27 July.
The Aviation Color Code was lowered to Yellow at 2317 on 28 July. Dates are
based on UTC times; specific events are in local time where noted.



Geologic Summary. The modern Bezymianny, much smaller than its massive
neighbors Kamen and Kliuchevskoi on the Kamchatka Peninsula, was formed
about 4,700 years ago over a late-Pleistocene lava-dome complex and an
edifice built about 11,000-7,000 years ago. Three periods of intensified
activity have occurred during the past 3,000 years. The latest period,
which was preceded by a 1,000-year quiescence, began with the dramatic
1955-56 eruption. This eruption, similar to that of St. Helens in 1980,
produced a large open crater that was formed by collapse of the summit and
an associated lateral blast. Subsequent episodic but ongoing lava-dome
growth, accompanied by intermittent explosive activity and pyroclastic
flows, has largely filled the 1956 crater.



Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
http://www.kscnet.ru/ivs/kvert/index_eng.php
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkRJOg4XiA$>





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



INGV reported that activity at Etnaâ??s summit craters continued during 24-28
July. Volcanologists conducted a field inspection of the summit area on 24
July, the day after intense activity that included Strombolian explosions
and lava fountaining at Voragine Crater, and lava overflows at Bocca Nuova
Crater. Explosive activity at Voragine Crater occurred at intervals of
35-40 minutes during the inspection and ejected material beyond the crater
rim. Lava flows originated from three breaches along Bocca Nuova Craterâ??s
WNW, W, and SW rim and continued to advance. The WNW flow traveled the
farthest, reaching 2,905 m elevation, followed by the W and SW flows that
reached 2,950 and 3,026 m elevations, respectively. The total volume of the
lava flows that breached the crater rim, the flows that pooled within the
crater, and ejected pyroclastic deposits, were estimated to be 2.4 x 10^6
cubic meters. Activity at Voragine Crater on 25 July was characterized by
intermittent explosive activity and a period of Strombolian activity.



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)
http://www.ct.ingv.it/
<https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkR_WNumgQ$>





Karymsky  | Eastern Kamchatka (Russia)  | 54.049°N, 159.443°E  | Summit
elev. 1513 m



KVERT reported moderate levels of activity at Karymsky during 18-25 July. A
thermal anomaly over the volcano was identified in satellite images during
19, 21-23, 25 July; weather clouds obscured views on the other days during
the week. The Aviation Color Code remained at Orange (the third level on a
four-color scale). Dates are based on UTC times; specific events are in
local time where noted.



Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern
volcanic zone, is a symmetrical stratovolcano constructed within a
5-km-wide caldera that formed during the early Holocene. The caldera cuts
the south side of the Pleistocene Dvor volcano and is located outside the
north margin of the large mid-Pleistocene Polovinka caldera, which contains
the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding
Karymsky eruptions originated beneath Akademia Nauk caldera, located
immediately south. The caldera enclosing Karymsky formed about 7600-7700
radiocarbon years ago; construction of the stratovolcano began about 2000
years later. The latest eruptive period began about 500 years ago,
following a 2300-year quiescence. Much of the cone is mantled by lava flows
less than 200 years old. Historical eruptions have been vulcanian or
vulcanian-strombolian with moderate explosive activity and occasional lava
flows from the summit crater.



Source: Kamchatkan Volcanic Eruption Response Team (KVERT)
http://www.kscnet.ru/ivs/kvert/index_eng.php
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkRJOg4XiA$>





Katla  | Iceland  | 63.633°N, 19.083°W  | Summit elev. 1490 m



Iceland Met Office (IMO) reported that electrical conductivity levels in
the Skálmur River, which drains from the Sandfellsjökull glacier on the E
part of the Mýrdalsjökull ice cap that covers Katla, began to increase late
on 26 July. Increased seismicity within the Katla caldera began to be
detected around 0600 on 27 July. Unrest significantly increased at around
1100 and a jökulhlaup (a glacier-outburst flood) began in the river at
around 1320. Reports indicated increased sulfur odors originating from
Mýrdalsjökull, specifically in Hólaskjól. As a precaution, and to account
for the possibility of volcanic unrest, at 1554 IMO raised the Aviation
Color Code to Yellow, the second lowest level on a four-color scale. The
flood water flowed over a 1-km-long section of Highway 1 (also known as the
Ring Road), damaging the road in several places, and washing away part of
the road located next to the Skálmur River bridge. According to a news
article local authorities closed the road between Víkur and
Kirkjubæjarklausturs and evacuated Sólheimajökull, an area near the
glacier, and a service area the end of the Sólheimajökull road. The peak
flow rate may have been as high as 1,000 cubic meters per second, making
the jökulhlaup significantly larger than previous events in 2011 and 1950.
Electrical conductivity levels indicated that the flooding had
significantly decreased later that night, though the report noted that it
may be days before the rivers return to seasonally normal levels. At 1031
on 29 July IMO lowered the Aviation Color Code to Green, noting that
activity at Mýrdalsjökull had returned to normal levels, and water levels
and electrical conductivity in the Skálmur River had decreased.



Geologic Summary. Katla volcano, located near the southern end of Iceland's
eastern volcanic zone, is hidden beneath the Myrdalsjökull icecap. The
subglacial basaltic-to-rhyolitic volcano is one of Iceland's most active
and is a frequent producer of damaging jökulhlaups, or glacier-outburst
floods. A large 10 x 14 km subglacial caldera with a long axis in a NW-SE
direction is up to 750 m deep. Its high point reaches 1380 m, and three
major outlet glaciers have breached its rim. Although most recorded
eruptions have taken place from fissures inside the caldera, the Eldgjá
fissure system, which extends about 60 km to the NE from the current ice
margin towards Grímsvötn volcano, has been the source of major Holocene
eruptions. An eruption from the Eldgjá fissure system about 934 CE produced
a voluminous lava flow of about 18 km3, one of the world's largest known
Holocene lava flows. Katla has been the source of frequent subglacial
basaltic explosive eruptions that have been among the largest
tephra-producers in Iceland during historical time and has also produced
numerous dacitic explosive eruptions during the Holocene.



Sources: Icelandic Meteorological Office (IMO) http://en.vedur.is/
<https://urldefense.com/v3/__http://en.vedur.is/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkTYB9iurQ$>
;

Icelandic National Broadcasting Service (RUV)
https://www.ruv.is/english/2023-08-30-glacial-flood-grows-on-river-skafta-390655
<https://urldefense.com/v3/__https://www.ruv.is/english/2023-08-30-glacial-flood-grows-on-river-skafta-390655__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkR29zmbrg$>
;

Icelandic National Broadcasting Service (RUV)
https://www.ruv.is/english/2024-07-28-glacial-flooding-has-destroyed-route-1-in-the-south-418538
<https://urldefense.com/v3/__https://www.ruv.is/english/2024-07-28-glacial-flooding-has-destroyed-route-1-in-the-south-418538__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkTSnZXcFw$>





Kelimutu  | Flores Island  | 8.77°S, 121.82°E  | Summit elev. 1639 m



PVMBG reported temperature increases at all three of Kelimutuâ??s crater
lakes and water-color changes at two of them based on 14 and 28 July field
observations and webcam images. The variations were most significant at
Crater I (Tiwu Ata Polo). The color of the water changed from brown on 14
July to blackish brown on 28 July and the temperature increased from 19 to
22 degrees Celsius. Water bubbles and/or upwelling in the NE part of the
lake were observed on both days. At Crater II (Tiwu Koofai Nuwamuri) the
water color was turquois green on 14 July. Light-yellow to golden-yellow
sulfur deposits were floating on the water in the central part on the lake
and along the S edge of the water on 14 July. There was a minor sulfur odor
and the water temperature was 25 degrees Celsius. By 28 July the water
color had changed to light blue and light-yellow sulfur deposits were
scattered on the surface in the central part of the lake and along the
margins. A sulfur odor was present and gas plumes rose as high as 100 m
above the waterâ??s surface. The water temperature had increased to 33
degrees Celsius. The color of the lake water at Crater III (Tiwu Ata Bupu)
remained at dark green during 14-28 July, but the temperature increased
from 16 to 19 degrees Celsius. Though the activity indicated increased
activity within the hydrothermal system, the Alert Level remained at 2 (on
a scale of 1-4) and the public was warned to stay 250 m from the crater
rims.



Geologic Summary. Kelimutu is a small, but well-known, Indonesian compound
volcano in central Flores Island with three summit crater lakes of varying
colors. The western lake, Tiwi Ata Mbupu (Lake of Old People) is commonly
blue. Tiwu Nua Muri Kooh Tai (Lake of Young Men and Maidens) and Tiwu Ata
Polo (Bewitched, or Enchanted Lake), which share a common crater wall, are
commonly colored green and red, respectively, although lake colors
periodically vary. Active upwelling, probably fed by subaqueous fumaroles,
occurs at the two eastern lakes. The scenic lakes are a popular tourist
destination and have been the source of minor phreatic eruptions in
historical time. The summit is elongated 2 km in a WNW-ESE direction; the
older cones of Kelido (3 km N) and Kelibara (2 km S).



Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known
as CVGHM) http://vsi.esdm.go.id/
<https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkQuq00Lrg$>





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



HVO reported that localized earthquake and ground deformation rates in
around Kilaueaâ??s upper East Rift Zone significantly increased twice during
22-23 July. The Volcano Alert Level was raised to Watch (the third level on
a four-level scale) and the Aviation Color Code was raised to Orange (the
third color on a four-color scale) at 0406 in response to the increases,
and then lowered back to Advisory and Yellow, respectively, at 0904 because
of a significant decrease in the activity; seismicity and ground
deformation rates remain elevated but at a lower intensity. Pulses of
increased seismicity were detected during 24-25 July; over 500 earthquakes
were recorded, including 12 events with magnitudes greater than 3.
Seismicity rapidly decreased to normal levels by midday on 25 July and
remained at low levels through 30 July. Minor deformation was detected.



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://volcanoes.usgs.gov/observatories/hvo/
<https://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkQPTKn8QQ$>





Nyamulagira  | DR Congo  | 1.408°S, 29.2°E  | Summit elev. 3058 m



A 30 July satellite image showed lava flows extending over 5 km NNW of
Nyamuragiraâ??s N crater rim and a new flow extending almost 2 km W of the NW
crater rim, based on thermal anomalies. Weather clouds obscured parts of
the NNW flow, possibly including the furthest extent of the flow. A
thermally anomalous area about 800 m E-W and more than 1.1 km N-S was
centered over the vent area in the crater.



Geologic Summary. Africa's most active volcano, Nyamulagira (also known as
Nyamuragira), is a massive high-potassium basaltic shield about 25 km N of
Lake Kivu and 13 km NNW of the steep-sided Nyiragongo volcano. The summit
is truncated by a small 2 x 2.3 km caldera that has walls up to about 100 m
high. Documented eruptions have occurred within the summit caldera, as well
as from the numerous flank fissures and cinder cones. A lava lake in the
summit crater, active since at least 1921, drained in 1938, at the time of
a major flank eruption. Recent lava flows extend down the flanks more than
30 km from the summit as far as Lake Kivu; extensive lava flows from this
volcano have covered 1,500 km2 of the western branch of the East African
Rift.



Source: Copernicus https://www.copernicus.eu/en
<https://urldefense.com/v3/__https://www.copernicus.eu/en__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkRWQQpDLw$>





Whakaari/White Island  | North Island (New Zealand)  | 37.52°S, 177.18°E  |
Summit elev. 294 m



GeoNet reported that a vigorous gas-and-steam plume containing ash was
visible in Whakatane and Te Kaha webcam images rising from Whakaari/White
Island during 0630-0730 on 26 July. The plume rose about 1 km and contained
a minor amount of ash at lower heights; ash fell on the W part of the
island. The Volcanic Alert Level remained at 2 (on a scale of 0-5) and the
Aviation Color Code remained at Yellow (the second level on a four-color
scale).



Geologic Summary. The uninhabited Whakaari/White Island is the 2 x 2.4 km
emergent summit of a 16 x 18 km submarine volcano in the Bay of Plenty
about 50 km offshore of North Island. The island consists of two
overlapping andesitic-to-dacitic stratovolcanoes. The SE side of the crater
is open at sea level, with the recent activity centered about 1 km from the
shore close to the rear crater wall. Volckner Rocks, sea stacks that are
remnants of a lava dome, lie 5 km NW. Descriptions of volcanism since 1826
have included intermittent moderate phreatic, phreatomagmatic, and
Strombolian eruptions; activity there also forms a prominent part of Maori
legends. The formation of many new vents during the 19th and 20th centuries
caused rapid changes in crater floor topography. Collapse of the crater
wall in 1914 produced a debris avalanche that buried buildings and workers
at a sulfur-mining project. Explosive activity in December 2019 took place
while tourists were present, resulting in many fatalities. The official
government name Whakaari/White Island is a combination of the full Maori
name of Te Puia o Whakaari ("The Dramatic Volcano") and White Island
(referencing the constant steam plume) given by Captain James Cook in 1769.



Source: GeoNet http://www.geonet.org.nz/
<https://urldefense.com/v3/__http://www.geonet.org.nz/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkT0-bNGYA$>





Yellowstone  | Eastern Snake River Plain  | 44.43°N, 110.67°W  | Summit
elev. 2805 m



The Yellowstone Volcano Observatory (YVO) reported that on 23 July a
hydrothermal explosion occurred at Yellowstoneâ??s Black Diamond Pool in the
Biscuit Basin thermal area. The explosion ejected a plume of water, mud,
and rock fragments 120-180 m high and NE towards Firehole River. Some
ejected boulders were more than a meter in diameter. A section of the
boardwalk to the S of the pool was notably damaged. The area, including the
parking lot and boardwalks, was closed to visitors after the explosion.
Hydrothermal explosions are relatively common in Yellowstone; on average,
there are a few of varying sizes somewhere in the park each year, often in
the backcountry where they may go unnoticed. The Volcano Alert Level
remained at Normal (the lowest level on a four-level scale) and the
Aviation Color Code remained at Green (the lowest color on a four-color
scale).



Geologic Summary. The Yellowstone Plateau volcanic field developed through
three volcanic cycles spanning two million years that included some of the
world's largest known eruptions. Eruption of the over 2,450 km3 Huckleberry
Ridge Tuff about 2.1 million years ago created the more than 75-km-long
Island Park caldera. The second cycle concluded with the eruption of the
Mesa Falls Tuff around 1.3 million years ago, forming the 16-km-wide Henrys
Fork caldera at the western end of the first caldera. Activity subsequently
shifted to the present Yellowstone Plateau and culminated 640,000 years ago
with the eruption of the over 1,000 km3 Lava Creek Tuff and the formation
of the present 45 x 85 km caldera. Resurgent doming subsequently occurred
at both the NE and SW sides of the caldera and voluminous (1000 km3)
intracaldera rhyolitic lava flows were erupted between 150,000 and 70,000
years ago. No magmatic eruptions have occurred since the late Pleistocene,
but large hydrothermal events took place near Yellowstone Lake during the
Holocene. Yellowstone is presently the site of one of the world's largest
hydrothermal systems, including Earth's largest concentration of geysers.



Source: Yellowstone Volcano Observatory (YVO)
https://www.usgs.gov/observatories/yvo
<https://urldefense.com/v3/__https://www.usgs.gov/observatories/yvo__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkTSN5n75Q$>





Ongoing Activity





Aira  | Kyushu (Japan)  | 31.5772°N, 130.6589°E  | Summit elev. 1117 m



JMA reported ongoing eruptive activity at Minamidake Crater (Aira Calderaâ??s
Sakurajima volcano) during 22-29 July. Nighttime crater incandescence was
visible in webcam images. An eruptive event at 0249 on 23 July produced an
ash plume that rose 1.1 km above the crater rim and drifted N. Sulfur
dioxide emissions were relatively low, averaging 800 tons per day (t/d) on
24 July, and lower than the average of 2,400 t/d on 5 July. Eruptive events
at 1155 on 27 July and at 0208, 0514, and 1439 on 28 July produced ash
plumes that rose 1-1.8 km above the crater rim and drifted mainly N. An
explosion at 1646 on 29 July generated a large ash plume that rose 4.4 km
above the crater rim and drifted SE and ejected large blocks 1.3-1.7 km
from the crater rim. An ash plume from an eruptive event at 1856 on 29 July
rose 1.1 km above the crater rim and drifted S. The Alert Level remained at
3 (on a 5-level scale), and the public was warned to stay 1 km away from
both craters.



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 caldera, along
with several post-caldera cones. The construction of Sakurajima began about
13,000 years ago on the southern rim and built an island that was joined to
the Osumi Peninsula during the major explosive and effusive eruption of
1914. Activity at the Kitadake summit cone ended about 4,850 years ago,
after which eruptions took place at Minamidake. Frequent eruptions since
the 8th century have deposited ash on the city of Kagoshima, located across
Kagoshima Bay only 8 km from the summit. The largest recorded eruption took
place during 1471-76.



Source: Japan Meteorological Agency (JMA) http://www.jma.go.jp/jma/
<https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkSon42SOA$>





Dukono  | Halmahera  | 1.6992°N, 127.8783°E  | Summit elev. 1273 m



PVMBG reported that the eruption at Dukono was ongoing during 24-30 July.
Gray-and-white ash plumes rose 100-900 m above the summit and drifted E and
NW during 24-26 and 30 July. White steam-and-gas plumes rose 100-700 m and
drifted E and NW on 27 and 29 July; emissions were not observed on 28 July.
The Alert Level remained at Level 2 (on a scale of 1-4), and the public was
warned to remain outside of the 3-km exclusion zone.



Geologic Summary. Reports from this remote volcano in northernmost
Halmahera are rare, but Dukono has been one of Indonesia's most active
volcanoes. More-or-less continuous explosive eruptions, sometimes
accompanied by lava flows, have occurred since 1933. During a major
eruption in 1550 CE, a lava flow filled in the strait between Halmahera and
the N-flank Gunung Mamuya cone. This complex volcano presents a broad, low
profile with multiple summit peaks and overlapping craters. Malupang
Wariang, 1 km SW of the summit crater complex, contains a 700 x 570 m
crater that has also been active during historical time.



Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known
as CVGHM) http://vsi.esdm.go.id/
<https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkQuq00Lrg$>





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



KVERT reported that moderate explosive activity was ongoing at Ebeko during
18-25 July. According to volcanologists in Severo-Kurilsk (Paramushir
Island, about 7 km E), explosions during 19-20 July generated ash plumes
that rose as high as 3.5 km (11,500 ft) a.s.l. and drifted NW, E, and SE.
Thermal anomalies were identified in satellite images those same days; on
other days either no activity was observed or weather conditions prevented
views. The Aviation Color Code remained at Orange (the third level on a
four-color scale). Dates are UTC; 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)
http://www.kscnet.ru/ivs/kvert/index_eng.php
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkRJOg4XiA$>





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



AVO reported that slow lava effusion in Great Sitkinâ??s summit crater
continued during 24-30 July; a 30 July radar image showed flow advancement
to the E and S. Seismicity was low with few small daily earthquakes. Weakly
elevated surface temperatures and steam emissions from the growing dome
were visible in satellite images during 28-30 July. Weather clouds often
obscured or partially obscured satellite and webcam views. The Volcano
Alert Level remained at Watch (the third level on a four-level scale) and
the Aviation Color Code remained at Orange (the third color on a four-color
scale).



Geologic Summary. The Great Sitkin volcano forms much of the northern side
of Great Sitkin Island. A younger 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
older edifice and produced a submarine debris avalanche. Deposits from this
and an even 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. Eruptions have been recorded
since the late-19th century.



Source: US Geological Survey Alaska Volcano Observatory (AVO)
https://avo.alaska.edu/
<https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkSRy-htCw$>





Ibu  | Halmahera  | 1.488°N, 127.63°E  | Summit elev. 1325 m



PVMBG reported that activity at Ibu continued during 24-30 July. Daily
white-and-gray ash plumes rose as high as 2.1 km above the summit and
drifted in multiple directions. Eruptive events were occasionally not
observable. Daily webcam images posted with the reports showed
incandescence emanating above the crater rim, possibly reflected in the
emissions. The Alert Level remained at 3 (the second highest level on a
four-level scale) and the public was advised to stay 4 km away from the
active crater and 5 km away from the N crater wall opening.



Geologic Summary. The truncated summit of Gunung Ibu stratovolcano along
the NW coast of Halmahera Island has large nested summit craters. The inner
crater, 1 km wide and 400 m deep, has contained several small crater lakes.
The 1.2-km-wide outer crater is breached on the N, creating a steep-walled
valley. A large cone grew ENE of the summit, and a smaller one to the WSW
has fed a lava flow down the W flank. A group of maars is located below the
N and W flanks. The first observed and recorded eruption was a small
explosion from the summit crater in 1911. Eruptive activity began again in
December 1998, producing a lava dome that eventually covered much of the
floor of the inner summit crater along with ongoing explosive ash emissions.



Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known
as CVGHM) http://vsi.esdm.go.id/
<https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkQuq00Lrg$>





Lewotobi  | Flores Island  | 8.542°S, 122.775°E  | Summit elev. 1703 m



PVMBG reported that eruptive activity at Lewotobiâ??s Laki-laki volcano
continued during 24-30 July. Gray or white-and-gray ash plumes that were
sometimes dense rose as high as 1 km above the summit and drifted mainly
SW, W, and NW on almost all days; an eruptive event was recorded on 28
July, though no emissions were observed. The Alert Level remained at 3 (the
second highest level on a scale of 1-4) and the public was warned to stay
outside of the exclusion zone, defined as a 3-km radius around both
Laki-laki and Perempuan craters, 4 km to the NNW and SSE of Laki-laki.



Geologic Summary. The Lewotobi edifice in eastern Flores Island is composed
of the two adjacent Lewotobi Laki-laki and Lewotobi Perempuan
stratovolcanoes (the "husband and wife"). Their summits are less than 2 km
apart along a NW-SE line. The conical Laki-laki to the NW has been
frequently active during the 19th and 20th centuries, while the taller and
broader Perempuan has had observed eruptions in 1921 and 1935. Small lava
domes have grown during the 20th century in both of the summit craters,
which are open to the north. A prominent cone, Iliwokar, occurs on the E
flank of Perampuan.



Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known
as CVGHM) http://vsi.esdm.go.id/
<https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkQuq00Lrg$>





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



BPPTKG reported that the eruption at Merapi (on Java) continued during
19-25 July. Earthquakes were less intense compared to the previous week.
The SW lava dome produced 126 lava avalanches that traveled as far as 1.9
km down the upper part of the Bebeng drainage. Five pyroclastic flows
traveled as far as 1.2 km down the Bebeng drainage. Morphological changes
to the SW lava dome were due to continuing effusion and collapses of
material and slight changes were detected at the dome in the main crater.
The volume of the SW dome was an estimated 2,538,700 cubic meters and the
dome in the main crater was stable at an estimated 2,360,700 cubic meters
based on webcam images and a 23 July drone survey. The hottest temperature
at the SW dome was around 219 degrees Celsius, similar to the previous
measurement. 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.



Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi
(BPPTKG) http://www.merapi.bgl.esdm.go.id/
<https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkTiYwUqAA$>





Reventador  | Ecuador  | 0.077°S, 77.656°W  | Summit elev. 3562 m



IG-EPN reported that an eruption at Reventador was ongoing during 23-30
July. Seismicity was characterized by 61-90 daily explosions, long-period
earthquakes, harmonic tremor, and tremor associated with emissions. Weather
conditions prevented visual observations during 23-25 July. Several
ash-and-gas plumes observed during 26-30 July rose as high as 1.1 km above
the crater rim and drifted N. NW, W, and SW. Avalanches of incandescent
material traveled 800-900 m down the flanks during 27-29 July. On 28 July a
pyroclastic flow descended the flanks as far as 600 m and on 29 July
pyroclastic flows descended the SE flank 600-800 m. During 29-30 July
ejected incandescent material fell onto the flanks as far as 400 m below
the crater rim. Secretaría de Gestión de Riesgos maintained the Alert Level
at Orange (the second highest level on a four-color scale).



Geologic Summary. Volcán El Reventador is the most frequently active of a
chain of Ecuadorian volcanoes in the Cordillera Real, well east of the
principal volcanic axis. The forested, dominantly andesitic stratovolcano
has 4-km-wide avalanche scarp open to the E formed by edifice collapse. A
young, unvegetated, cone rises from the amphitheater floor to a height
comparable to the rim. It has been the source of numerous lava flows as
well as explosive eruptions visible from Quito, about 90 km ESE. Frequent
lahars in this region of heavy rainfall have left extensive deposits on the
scarp slope. The largest recorded eruption took place in 2002, producing a
17-km-high eruption column, pyroclastic flows that traveled up to 8 km, and
lava flows from summit and flank vents.



Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
http://www.igepn.edu.ec/
<https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkQPJjKypA$>
;

Secretaría de Gestión de Riesgos (SGR) http://www.gestionderiesgos.gob.ec/
<https://urldefense.com/v3/__http://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkSI2M0POg$>





Sabancaya  | Peru  | 15.787°S, 71.857°W  | Summit elev. 5960 m



Instituto Geofísico del Perú (IGP) reported that the eruption at Sabancaya
continued at moderate levels during 22-29 July with a daily average of 56
explosions. Gas-and-ash plumes rose as high as 3.1 km above the summit and
drifted less than 10 km S and SE. Thermal anomalies over the lava dome in
the summit crater were identified in satellite data. Slight inflation was
detected N of Hualca Hualca (7 km N). Sulfur dioxide emissions were at
moderate levels, averaging 608 tons per day. The Alert Level remained at
Orange (the third level on a four-color scale) and the public was warned to
stay outside of a 12 km radius.



Geologic Summary. Sabancaya, located in the saddle NE of Ampato and SE of
Hualca Hualca volcanoes, is the youngest of these volcanic centers and the
only one to have erupted in historical time. The oldest of the three,
Nevado Hualca Hualca, is of probable late-Pliocene to early Pleistocene
age. The name Sabancaya (meaning "tongue of fire" in the Quechua language)
first appeared in records in 1595 CE, suggesting activity prior to that
date. Holocene activity has consisted of Plinian eruptions followed by
emission of voluminous andesitic and dacitic lava flows, which form an
extensive apron around the volcano on all sides but the south. Records of
observed eruptions date back to 1750 CE.



Source: Instituto Geofísico del Perú (IGP) http://www.igp.gob.pe/
<https://urldefense.com/v3/__http://www.igp.gob.pe/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkRBrakU4Q$>





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



IG-EPN reported that high levels of eruptive activity continued at Sangay
during 23-30 July. The seismic network recorded 1,175-1,840 daily
explosions. Daily gas-and-ash plumes were visible in webcam and/or
satellite images and rose 500-2,500 m above the summit and drifted mainly
NW, W, and SW. Incandescent material at the summit crater was periodically
visible during dark hours, and several episodes of incandescent material
were visible descending the SE drainage as far as 2 km during 23-28 July;
weather conditions often obscured views. On 24 July a pyroclastic flow
traveled 2 km down the SE drainage. Minor ashfall was reported in towns in
the Chimborazo province including Alausí (60 km SW) and Guarguallá (25 km
WNW) during 24-25 July, Alausí during 27-29 July, and Chunchi (73 km SW) on
30 July. Secretaría de Gestión de Riesgos (SGR) maintained the Alert Level
at Yellow (the second highest level on a four-color scale).



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.



Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)
http://www.igepn.edu.ec/
<https://urldefense.com/v3/__http://www.igepn.edu.ec/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkQPJjKypA$>
;

Secretaría de Gestión de Riesgos (SGR) http://www.gestionderiesgos.gob.ec/
<https://urldefense.com/v3/__http://www.gestionderiesgos.gob.ec/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkSI2M0POg$>





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



KVERT reported that thermal anomalies over both the â??300 years of RASâ?? dome
on the SW flank of Old Sheveluch and the lava dome in the crater of Young
Sheveluch were identified in satellite images during 18-25 July. The
Aviation Color Code remained at Orange (the third 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)
http://www.kscnet.ru/ivs/kvert/index_eng.php
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkRJOg4XiA$>





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



JMA reported that eruptive activity at Suwanosejima's Ontake Crater
continued during 22-29 July. Crater incandescence was observed nightly in
webcam images. An explosion at 1527 on 24 July produced an ash plume that
rose 700 m above the crater rim and drifted W. Another explosion was
detected at 1231 on 25 July, though details about possible emissions were
unknown. The Alert Level remained at 2 (on a 5-level scale) and the public
was warned to stay at least 1.5 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 active
summit craters. The summit is truncated by a large breached crater
extending to the sea on the E 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 covered
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 an open collapse
scarp extending 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) http://www.jma.go.jp/jma/
<https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkSon42SOA$>





Ubinas  | Peru  | 16.345°S, 70.8972°W  | Summit elev. 5608 m



Instituto Geofísico del Perú (IGP) reported that during 24-30 July daily
seismicity at Ubinas was characterized by 55-116 events associated with
rock fracturing and 49-129 events associated with fluid movement.
Gas-and-steam emissions were sometimes visible rising 200-600 m above the
crater rim. Daily thermal anomalies were identified in satellite images.
The Alert Level remained at Yellow (the second level on a four-color scale)
and the public was warned to stay 2 km away from the crater.



Geologic Summary. The truncated appearance of Ubinas, Perú's most active
volcano, is a result of a 1.4-km-wide crater at the summit. It is the
northernmost of three young volcanoes located along a regional structural
lineament about 50 km behind the main volcanic front. The growth and
destruction of Ubinas I was followed by construction of Ubinas II beginning
in the mid-Pleistocene. The upper slopes of the andesitic-to-rhyolitic
Ubinas II stratovolcano are composed primarily of andesitic and
trachyandesitic lava flows and steepen to nearly 45°. The steep-walled,
150-m-deep summit crater contains an ash cone with a 500-m-wide
funnel-shaped vent that is 200 m deep. Debris-avalanche deposits from the
collapse of the SE flank about 3,700 years ago extend 10 km from the
volcano. Widespread Plinian pumice-fall deposits include one from about
1,000 years ago. Holocene lava flows are visible on the flanks, but
activity documented since the 16th century has consisted of intermittent
minor-to-moderate explosive eruptions.



Source: Instituto Geofísico del Perú (IGP) http://www.igp.gob.pe/
<https://urldefense.com/v3/__http://www.igp.gob.pe/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkRBrakU4Q$>





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



Servicio Nacional de Geología y Minería (SERNAGEOMIN) reported that an
explosion at Villarrica ejected incandescent material around 190 m above
the crater rim on 24 July. Some of the incandescent material landed on the
flanks and rolled short distances based on the webcam view posted with the
report. According to POVI a series of phreatomagmatic pulses on 29 July
produced ash plumes and ashfall on the upper E flank. The Volcanic Alert
level remained at Yellow (the third level on a four-level scale) and the
public was warned to stay 1.5 km away from the crater. SENAPRED maintained
the Alert Level at Yellow (the middle level on a three-color scale) for the
communities of Villarrica, Pucón (16 km N), Curarrehue, and Panguipulli.



Geologic Summary. The glacier-covered Villarrica stratovolcano, in the
northern Lakes District of central Chile, is ~15 km south of the city of
Pucon. A 2-km-wide caldera that formed about 3,500 years ago is located at
the base of the presently active, dominantly basaltic to basaltic-andesite
cone at the NW margin of a 6-km-wide Pleistocene caldera. More than 30
scoria cones and fissure vents are present on 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. Eruptions documented since 1558 CE 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: Servicio Nacional de Geología y Minería (SERNAGEOMIN)
http://www.sernageomin.cl/
<https://urldefense.com/v3/__http://www.sernageomin.cl/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkTZUMoBYQ$>
;

Sistema y Servicio Nacional de Prevención y Repuesta Ante Desastres
(SENAPRED) https://senapred.cl/
<https://urldefense.com/v3/__https://senapred.cl/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkS0gMvM_Q$>
;

Proyecto Observación Villarrica Internet (POVI) http://www.povi.cl/
<https://urldefense.com/v3/__http://www.povi.cl/__;!!IKRxdwAv5BmarQ!bUJLE7NI6tw_FwxyR-zsaUUpCKF9PX9YihV1gtPbGgqiWuqb_uZULV1PMQ3xemTuhgLcJlAoJrIpBtOXfkTAICkrfQ$>


5-5-5-5-5-5-5-5-5-5-5-5-5-5



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End of Volcano Digest - 26 Jul 2024 to 31 Jul 2024 (#2024-67)
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