Smithsonian / USGS Weekly Volcanic Activity Report 3-9 August 2022

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7-7-7-7-7-7-7-7-7-7-7-7-7-7


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


Smithsonian / USGS Weekly Volcanic Activity Report

3-9 August 2022



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

URL: https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiEpFoQF7$ 
<https://urldefense.com/v3/__https://volcano.si.edu/reports_weekly.cfm__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9blSRE6U$>





New Activity/Unrest: Aira, Kyushu (Japan)  | Grimsvotn, Iceland  | Ioto,
Volcano Islands  | Krysuvik-Trolladyngja, Reykjanes Peninsula



Ongoing Activity: Ebeko, Paramushir Island (Russia)  | Fuego, South-Central
Guatemala  | Great Sitkin, Andreanof Islands (USA)  | Karymsky, Eastern
Kamchatka (Russia)  | Kilauea, Hawaiian Islands (USA)  | Krakatau, Sunda
Strait  | Lewotolok, Lembata Island  | Merapi, Central Java  | Nevado del
Ruiz, Colombia  | Pavlof, Alaska Peninsula, Alaska  | Sabancaya, Peru  |
Santa Maria, Southwestern Guatemala  | Semeru, Eastern Java  | Sheveluch,
Central Kamchatka (Russia)  | Stromboli, Aeolian Islands (Italy)  |
Suwanosejima, Ryukyu Islands (Japan)  | Taal, Luzon (Philippines)





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





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



JMA reported that nighttime incandescence at Minamidake Crater (at Aira
Calderaâ??s Sakurajima volcano) was visible during 1-8 August. The seismic
network recorded 25 eruptive events and seven explosions. Volcanic plumes
rose as high as 2.8 km above the crater rim and material was ejected
material as high as 1.3 km above the summit. 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!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiLAIH3nr$ 
<https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9RUR_7Yc$>





Grimsvotn  | Iceland  | 64.416°N, 17.316°W  | Summit elev. 1719 m



The Icelandic Meteorological Office (IMO) reported that seismicity at
Grímsvötn had declined to normal levels during the past few days, and no
significant variations from background levels were observed in geochemical
or deformation data. On 9 August the Aviation Color Code was lowered to
Green.



Geologic Summary. Grímsvötn, Iceland's most frequently active volcano in
recent history, lies largely beneath the vast Vatnajökull icecap. The
caldera lake is covered by a 200-m-thick ice shelf, and only the southern
rim of the 6 x 8 km caldera is exposed. The geothermal area in the caldera
causes frequent jökulhlaups (glacier outburst floods) when melting raises
the water level high enough to lift its ice dam. Long NE-SW-trending
fissure systems extend from the central volcano. The most prominent of
these is the noted Laki (Skaftar) fissure, which extends to the SW and
produced the world's largest known historical lava flow in 1783. The 15 km3
basaltic Laki lavas were erupted over a 7-month period from a 27-km-long
fissure system. Extensive crop damage and livestock losses caused a severe
famine that resulted in the loss of one-fifth of the population of Iceland.



Source: Icelandic Meteorological Office (IMO) https://urldefense.com/v3/__http://en.vedur.is/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiLG5QfMf$ 
<https://urldefense.com/v3/__http://en.vedur.is/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9zm8oY2I$>





Ioto  | Volcano Islands  | 24.751°N, 141.289°E  | Summit elev. 169 m



JMA reported that minor eruptive activity off the coast at Ioto (Iwo-jima)
had been visible daily during 11-31 July. On 14 July pumice pieces from the
eruption washed up onto the shore at Onohama and were photographed during a
field survey conducted by the National Research Institute for Earth Science
and Disaster Prevention. JMA scientist visited the site on 31 July and
confirmed the pumice deposits on the beach. They saw eruptive activity
every few minutes, and gray, tephra-laden columns of water being ejected
20-30 m above the oceanâ??s surface. A satellite image on 4 August showed a
small rounded gray zone at the water surface and a plume of discolored
water drifting NE.



Geologic Summary. Ioto in the central Volcano Islands portion of the
Izu-Marianas arc lies within a 9-km-wide submarine caldera. Ioto, Iwojima,
and Iojima are among many transliterations of the name. The volcano is also
known as Ogasawara-Iojima to distinguish it from several other "Sulfur
Island" volcanoes in Japan. The triangular, low-elevation, 8-km-long island
narrows toward its SW tip and has produced trachyandesitic and trachytic
rocks that are more alkalic than those of other Izu-Marianas arc volcanoes.
The island has undergone dramatic uplift for at least the past 700 years
accompanying resurgent doming of the caldera. A shoreline landed upon by
Captain Cook's surveying crew in 1779 is now 40 m above sea level. The
Motoyama plateau on the NE half of the island consists of submarine tuffs
overlain by coral deposits and forms the island's high point. Many
fumaroles are oriented along a NE-SW zone cutting through Motoyama.
Numerous historical phreatic eruptions, many from vents on the west and NW
sides of the island, have accompanied the remarkable uplift.



Sources: Japan Meteorological Agency (JMA) https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiLAIH3nr$ 
<https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9RUR_7Yc$>
;

Sentinel Hub https://urldefense.com/v3/__https://sentinel-hub.com/explore/sentinel-playground__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiH2yhfZ4$ 
<https://urldefense.com/v3/__https://sentinel-hub.com/explore/sentinel-playground__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9rWF_i70$>





Krysuvik-Trolladyngja  | Reykjanes Peninsula  | 63.917°N, 22.067°W  |
Summit elev. 360 m



The fissure eruption of the Krýsuvík-Trölladyngja volcanic system that
began at around 1318 on 3 August continued at least through 9 August.
Numerous small lava fountains rose along the fissure, located near the
border of the previous flow field N of Fagradalsfjall, and lava flows
traveled downslope to the NW. Scientists from the Institute of Earth
Sciences stated that the initial flow rate was 5-10 times greater than the
flow rate at the start of the 2021 eruption, based on model estimates,
field data, and satellite measurements. The flow rate was about 32 cubic
meters per second during the initial hours of the eruption, then decreased
to an average of 18 cubic meters per second from 1700 on 3 August until
1100 on 4 August, by which time about 1.6 million cubic meters of lava had
covered an area of 0.14 square kilometers. The average flow thickness was
around 11 m. According to a news article the length of the active fissure
had decreased and the middle part of the fissure was the most active. On 5
August Icelandic Meteorological Office (IMO) reported that the number of
daily earthquakes declined after the eruption began and deformation
stabilized. Thousands of people were walking on the trails to view the
eruption; authorities warned the public to heed inclement weather warnings,
and closed access to the site during 7-9 August due to weather conditions
and trail maintenance.



Geologic Summary. The Krýsuvík-Trölladyngja volcanic system is described by
the Catalogue of Icelandic Volcanoes as an approximately 50-km-long
composite fissure swarm trending about N38°E, including a 30-km-long swarm
of fissures, with no central volcano. It is one of the volcanic systems
arranged en-echelon along the Reykjanes Peninsula west of Kleifarvatn lake.
The Fagradalsfjall and Krýsuvík fissure swarms are considered splits or
secondary swarms of the Krýsuvíkâ??Trölladyngja volcanic system. Small shield
volcanoes have produced a large portion of the erupted volume within the
system. Several eruptions have taken place since the settlement of Iceland,
including the eruption of a large basaltic lava flow from the Ogmundargigar
crater row around the 12th century. The latest eruption, identified through
tephrochronology, took place during the 14th century.



Sources: Icelandic Meteorological Office (IMO) https://urldefense.com/v3/__http://en.vedur.is/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiLG5QfMf$ 
<https://urldefense.com/v3/__http://en.vedur.is/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9zm8oY2I$>
;

Institute of Earth Sciences https://urldefense.com/v3/__http://www.earthice.hi.is/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiLOeHw5C$ 
<https://urldefense.com/v3/__http://www.earthice.hi.is/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9nVOQNGk$>
;

Icelandic National Broadcasting Service (RUV)
https://urldefense.com/v3/__https://www.ruv.is/frett/2022/08/04/fissure-could-extend-northwards__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiNTi1biN$ 
<https://urldefense.com/v3/__https://www.ruv.is/frett/2022/08/04/fissure-could-extend-northwards__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw97Ka79gU$>
;

Icelandic National Broadcasting Service (RUV)
https://urldefense.com/v3/__https://www.ruv.is/frett/2022/08/09/meradalir-closed-until-tomorrow__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiJkeWl8a$ 
<https://urldefense.com/v3/__https://www.ruv.is/frett/2022/08/09/meradalir-closed-until-tomorrow__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9Qhvi6yk$>
;

Icelandic National Broadcasting Service (RUV)
https://urldefense.com/v3/__https://www.ruv.is/frett/2022/08/06/weather-warning-could-stop-volcano-visits-tomorrow__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiPsaq9Ut$ 
<https://urldefense.com/v3/__https://www.ruv.is/frett/2022/08/06/weather-warning-could-stop-volcano-visits-tomorrow__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9k1yETRA$>





Ongoing Activity





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



KVERT reported that moderate activity at Ebeko was ongoing during 28 July-4
August. According to volcanologists in Severo-Kurilsk (Paramushir Island,
about 7 km E) explosions generated ash plumes that rose up to 4.5 km
(14,800 ft) a.s.l. and drifted in multiple directions. A thermal anomaly
over the volcano was identified in satellite images during 1 and 3-4
August. 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!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiBoPyTe7$ 
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9NE_BW2I$>





Fuego  | South-Central Guatemala  | 14.473°N, 90.88°W  | Summit elev. 3763 m



INSIVUMEH reported that 3-10 explosions per hour were recorded at Fuego
during 2-9 August, generating ash plumes that rose as high as 1.1 km above
the crater rim. The ash plumes drifted as far as 30 km W and SW, causing
daily ashfall in areas downwind including Morelia (9 km SW), Panimaché I
and II (8 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), Los
Yucales (12 km SW), Sangre de Cristo (8 km WSW), El Porvenir (8 km ENE),
San Pedro Yepocapa (8 km NW), Ojo de Agua, and Finca Palo Verde. Daily
shock waves rattled structures in communities around the volcano and
rumbling was occasionally heard. Daily block avalanches descended the
Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Honda, and Las Lajas
(SE) drainages. Explosions ejected incandescent material 100-300 m above
the summit each day.



Geologic Summary. Volcán Fuego, one of Central America's most active
volcanoes, is also one of three large stratovolcanoes overlooking
Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta,
lies between Fuego and Acatenango to the north. Construction of Meseta
dates back to about 230,000 years and continued until the late Pleistocene
or early Holocene. Collapse of Meseta may have produced the massive
Escuintla debris-avalanche deposit, which extends about 50 km onto the
Pacific coastal plain. Growth of the modern Fuego volcano followed,
continuing the southward migration of volcanism that began at the mostly
andesitic Acatenango. Eruptions at Fuego have become more mafic with time,
and most historical activity has produced basaltic rocks. Frequent vigorous
historical eruptions have been recorded since the onset of the Spanish era
in 1524, and have produced major ashfalls, along with occasional
pyroclastic flows and lava flows.



Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e
Hidrologia (INSIVUMEH) https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiL4kiUyY$ 
<https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9YcfqMo8$>





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



AVO reported that slow lava effusion at Great Sitkin likely continued
during 2-9 August; no changes to the flow lengths were visible but the lava
had deepened around the vent. Weather clouds often obscured satellite and
webcam views during most of the week, though no activity was visible when
views were clear. Seismicity was low and occasional local earthquakes were
recorded. Elevated surface temperatures were identified in satellite images
during 5-9 August. The Aviation Color Code and the Volcano Alert Level
remained at Orange and Watch, respectively.



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!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiNbuqsVt$ 
<https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9O6z7IXs$>





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



KVERT reported that the eruption at Karymsky continued during 29 July-4
August. Explosions during 29-31 July, 1-2 August, and 4 August produced ash
plumes that rose 4-8 km (13,100-26,200 ft) a.s.l. and drifted 230 km S, SE,
and E. A thermal anomaly over the volcano was identified in satellite
images during 31 July-4 August. 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. 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)
https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiBoPyTe7$ 
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9NE_BW2I$>





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 2-9 August, entering the lava lake
and flowing onto the crater floor. The lake level remained within the
bounding levees. Daily minor ooze-outs were visible along the margins of
the crater floor. Intense incandescence from the W vent was visible during
5-9 August. Aviation Color Code and the Volcano Alert Level remained at
Orange and Watch, respectively.



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!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiHv3Zvr4$ 
<https://urldefense.com/v3/__https://volcanoes.usgs.gov/observatories/hvo/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9zTWNAEU$>





Krakatau  | Sunda Strait  | 6.102°S, 105.423°E  | Summit elev. 155 m



PVMBG reported that the eruption at Anak Krakatau continued during 3-9
August. Several eruptive events occurred on 3 August (at 0034, 0115, and
1540), sometimes producing dense black ash plumes that rose as high as 1.5
km above the summit and drifted SW. At 0926 on 4 August a dense
gray-to-black ash plume rose 1.5 km and drifted N. Incandescence at or near
the vent was seen in nighttime photos on most days. Diffuse white plumes
were visible rising from the volcano during 7-8 August. The Alert Level
remained at 3 (on a scale of 1-4), and the public was warned to stay at
least 5 km away from the crater.



Geologic Summary. The renowned volcano Krakatau (frequently misstated as
Krakatoa) lies in the Sunda Strait between Java and Sumatra. Collapse of
the ancestral edifice, perhaps in 416 or 535 CE, formed a 7-km-wide
caldera. Remnants of that volcano are preserved in Verlaten and Lang
Islands; subsequently Rakata, Danan, and Perbuwatan volcanoes were formed,
coalescing to create the pre-1883 Krakatau Island. Caldera collapse during
the catastrophic 1883 eruption destroyed Danan and Perbuwatan, and left
only a remnant of Rakata. This eruption caused more than 36,000 fatalities,
most as a result of tsunamis that swept the adjacent coastlines of Sumatra
and Java. Pyroclastic surges traveled 40 km across the Sunda Strait and
reached the Sumatra coast. After a quiescence of less than a half century,
the post-collapse cone of Anak Krakatau (Child of Krakatau) was constructed
within the 1883 caldera at a point between the former cones of Danan and
Perbuwatan. Anak Krakatau has been the site of frequent eruptions since
1927.



Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known
as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiGTayCZO$ 
<https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw91YFkygs$>





Lewotolok  | Lembata Island  | 8.274°S, 123.508°E  | Summit elev. 1431 m



PVMBG reported that the Strombolian eruption at Lewotolok continued during
2-9 August. Daily white or white-and-gray emissions rose as high as 400 m
above the summit and drifted in multiple directions. Photos in some posted
reports showed Strombolian activity. The Alert Level remained at 3 (on a
scale of 1-4) and the public was warned to stay 3 km away from the summit
crater and 4 km away from the crater on the SE flank.



Geologic Summary. The Lewotolok (or Lewotolo) stratovolcano occupies the
eastern end of an elongated peninsula extending north into the Flores Sea,
connected to Lembata (formerly Lomblen) Island by a narrow isthmus. It is
symmetrical when viewed from the north and east. A small cone with a
130-m-wide crater constructed at the SE side of a larger crater forms the
volcano's high point. Many lava flows have reached the coastline. Eruptions
recorded since 1660 have consisted of explosive activity from the summit
crater.



Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known
as CVGHM) https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiGTayCZO$ 
<https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw91YFkygs$>





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



BPPTKG reported that the eruption at Merapi continued during 29 July-4
August. Seismicity remained at high levels. As many as 34 lava avalanches
traveled down the Bebeng drainage on the SW flank, reaching a maximum
distance of 1.8 km. The volumes of both the SW and central lava domes were
unchanged based on photo analyses. 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) https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiFytAz4t$ 
<https://urldefense.com/v3/__http://www.merapi.bgl.esdm.go.id/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9SXOFMaw$>





Nevado del Ruiz  | Colombia  | 4.892°N, 75.324°W  | Summit elev. 5279 m



On 2 August Servicio Geológico Colombianoâ??s (SGC) reported that during the
previous week the number and size of seismic signals indicating fluid
movement had increased at Nevado del Ruiz compared to the week before,
though they remained at moderate levels. Although seismic signals
indicating rock fracturing increased in number, magnitudes were similar to
the previous week. Several episodes of drumbeat seismicity were recorded,
indicating continuing growth of the lava dome. Gas-and-steam emissions rose
from the crater, reaching just over 2.4 km above the summit on 30 July.
Several thermal anomalies in Arenas Crater were identified in satellite
images during 0500-0600 on 4 August, and seismic signals indicating
emissions were recorded during 4-5 August. Ashfall was reported in the
municipalities of Santa Rosa de Cabal, Pereira, Villamaría, Manizales, and
Dosquebradas. Tephra deposits were visible near the crater and in areas up
to 3 km away. The Alert Level remained at 3 (Yellow; the second lowest
level on a four-color scale).



Geologic Summary. Nevado del Ruiz is a broad, glacier-covered volcano in
central Colombia that covers more than 200 km2. Three major edifices,
composed of andesitic and dacitic lavas and andesitic pyroclastics, have
been constructed since the beginning of the Pleistocene. The modern cone
consists of a broad cluster of lava domes built within the caldera of an
older edifice. The 1-km-wide, 240-m-deep Arenas crater occupies the summit.
The prominent La Olleta pyroclastic cone located on the SW flank may also
have been active in historical time. Steep headwalls of massive landslides
cut the flanks. Melting of its summit icecap during historical eruptions,
which date back to the 16th century, has resulted in devastating lahars,
including one in 1985 that was South America's deadliest eruption.



Source: Servicio Geológico Colombiano (SGC)
https://urldefense.com/v3/__https://www2.sgc.gov.co/volcanes/index.html__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiJB-z9V6$ 
<https://urldefense.com/v3/__https://www2.sgc.gov.co/volcanes/index.html__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9Fv5biP8$>





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 3-9 August. Seismic tremor persisted and multiple daily
explosions were detected in local and regional seismic and infrasound data.
The explosions likely produced minor ash emissions that rose no higher than
3 km (10,000 ft) a.s.l., though cloud cover prevented confirmation on most
days. Strongly elevated surface temperatures were identified in satellite
images during 7-8 August. The Volcano Alert Level remained at Watch and the
Aviation Color Code remained at Orange.



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!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiNbuqsVt$ 
<https://urldefense.com/v3/__https://avo.alaska.edu/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9O6z7IXs$>





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



Instituto Geofísico del Perú (IGP) reported moderate levels of activity at
Sabancaya during 1-7 August with a daily average of 19 explosions.
Gas-and-ash plumes rose as high as 2.7 km above the summit and drifted E,
SE, SW, and W. As many as seven thermal anomalies originating from the lava
dome in the summit crater were identified in satellite data. Minor
inflation continued to be detected near Hualca Hualca (4 km N). The Alert
Level remained at Orange (the second highest level on a four-color scale)
and the public were 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
historical eruptions date back to 1750.



Source: Instituto Geofísico del Perú (IGP) https://urldefense.com/v3/__http://www.igp.gob.pe/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiEhsJ6_E$ 
<https://urldefense.com/v3/__http://www.igp.gob.pe/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9sCjNs3g$>





Santa Maria  | Southwestern Guatemala  | 14.757°N, 91.552°W  | Summit elev.
3745 m



INSIVUMEH reported that the eruption at Santa Maríaâ??s Santiaguito lava-dome
complex continued during 2-9 August. Lava flows continued to advance in the
San Isidro and El Tambor drainages on the W and SW flanks and were as long
as 3.7 km by 5 August. Block avalanches from the W part of Caliente cone,
and from both the ends and sides of the flows descended the S, SW, and W
flanks. The avalanches generated ash plumes that rose about 1 km and
drifted SW, S, and E, causing ashfall in areas downwind including La
Florida, Monte Claro, San Marcos Palajunoj, Loma Linda, and Las Marías.
Incandescence from Caliente cone and the lava-flow fronts was sometimes
visible at night.



Geologic Summary. Symmetrical, forest-covered Santa María volcano is part
of a chain of large stratovolcanoes that rise above the Pacific coastal
plain of Guatemala. The sharp-topped, conical profile is cut on the SW
flank by a 1.5-km-wide crater. The oval-shaped crater extends from just
below the summit to the lower flank, and was formed during a catastrophic
eruption in 1902. The renowned Plinian eruption of 1902 that devastated
much of SW Guatemala followed a long repose period after construction of
the large basaltic-andesite stratovolcano. The massive dacitic Santiaguito
lava-dome complex has been growing at the base of the 1902 crater since
1922. Compound dome growth at Santiaguito has occurred episodically from
four vents, with activity progressing W towards the most recent, Caliente.
Dome growth has been accompanied by almost continuous minor explosions,
with periodic lava extrusion, larger explosions, pyroclastic flows, and
lahars.



Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e
Hidrologia (INSIVUMEH) https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiL4kiUyY$ 
<https://urldefense.com/v3/__http://www.insivumeh.gob.gt/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9YcfqMo8$>





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



PVMBG reported that the eruption at Semeru continued during 3-9 August.
Eruptive events recorded at 0810 on 3 August, 0628 on 4 August, 1245 on 5
August, and 0720 on 6 August produced ash plumes that rose 500-700 m above
the summit and drifted SW and 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!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiGTayCZO$ 
<https://urldefense.com/v3/__http://vsi.esdm.go.id/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw91YFkygs$>





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



KVERT reported that the ongoing eruption at Sheveluch was characterized by
explosions, hot avalanches, and lava-dome extrusion during 29 July-4
August. A daily thermal anomaly was identified in satellite images, and ash
plumes were visible drifting 24 km SW on 31 July. 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 1300 km3 volcano is one of Kamchatka's largest and most
active volcanic structures. 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 dot its outer flanks. The Molodoy
Shiveluch lava dome complex was constructed during the Holocene within the
large horseshoe-shaped caldera; Holocene lava dome extrusion also took
place on the flanks of Stary Shiveluch. At least 60 large eruptions have
occurred during the Holocene, making it the most vigorous andesitic volcano
of the Kuril-Kamchatka arc. 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!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiBoPyTe7$ 
<https://urldefense.com/v3/__http://www.kscnet.ru/ivs/kvert/index_eng.php__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9NE_BW2I$>





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



INGV reported that during 1-7 August activity at Stromboli was
characterized by ongoing explosions from two vents in Area N (North Crater
area) and two vents in Area C-S (South-Central Crater area). Low-intensity
explosions from the N1 vent (Area N) ejected mostly ash, with some course
material, 80-150 m high at a rate of 2-6 explosions per hour. The N2 vent
(Area N) emitted gases. No explosions occurred at the S1 and C vents in
Area C-S; low-intensity explosions at two S2 vents ejected coarse material
80-150 m high at a rate of 3-4 explosions per hour.



Geologic Summary. Spectacular incandescent nighttime explosions at this
volcano have long attracted visitors to the "Lighthouse of the
Mediterranean." Stromboli, the NE-most of the Aeolian Islands, 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 horseshoe-shaped scarp formed about 5,000 years ago due to a
series of slope failures that extend 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!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiNkvzdGh$ 
<https://urldefense.com/v3/__http://www.ct.ingv.it/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9dWl3zpw$>





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



JMA reported that the number of explosions at Suwanosejima's Ontake Crater
increased during 2-8 August, when around 30 were recorded; nine of those
were detected on 7 August. During 7-8 August eruption plumes rose as high
as 2 km above the crater rim and mingled with weather clouds. Large
ballistics were ejected 600 m from the craterâ??s center. Incandescence from
the crater was visible at night. The Alert Level remained at 2 and the
public was warned to stay 1 km away from the crater.



Geologic Summary. The 8-km-long, spindle-shaped 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. Suwanosejima, one of Japan's most frequently active
volcanoes, was in a state of intermittent strombolian activity from Otake,
the NE summit crater, that began in 1949 and lasted until 1996, after which
periods of inactivity lengthened. The largest historical 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 horseshoe-shaped 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!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiLAIH3nr$ 
<https://urldefense.com/v3/__http://www.jma.go.jp/jma/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9RUR_7Yc$>





Taal  | Luzon (Philippines)  | 14.002°N, 120.993°E  | Summit elev. 311 m



PHIVOLCS reported increases in both sulfur dioxide emissions at Taal and
activity in Main Crater Lake. Sulfur dioxide emissions averaged 1,289
tonnes per day from May to mid-June, and increased to an average of 4,952
tonnes per day during 15 July-3 August. Sulfur dioxide emissions further
increased to 12,125 and 17,141 tonnes per day on 3 and 7 August,
respectively, prompting PHIVOLCS to issue advisories. Vog was present over
the W part of Taal Caldera during 2-3 August; dense vog in Laurel and
Banyaga (Agoncillo, Batangas Province) also damaged vegetation. A sulfur
odor was reported by residents of Tagaytay City and Bugaan East. Upwelling
gasses and hot fluids in the lake, and voluminous steam-rich plumes rising
as high as 2.8 km above the lake, were visible during 1-9 August. Recent
low-frequency seismic events and tremor were characterized as above
background. The Alert Level remained at 1 (on a scale of 0-5), and PHIVOLCS
reminded the public that the entire Taal Volcano Island was a Permanent
Danger Zone (PDZ).



Geologic Summary. Taal is one of the most active volcanoes in the
Philippines and has produced some of its most powerful historical
eruptions. Though not topographically prominent, its prehistorical
eruptions have greatly changed the landscape of SW Luzon. The 15 x 20 km
Talisay (Taal) caldera is largely filled by Lake Taal, whose 267 km2
surface lies only 3 m above sea level. The maximum depth of the lake is 160
m, and several eruptive centers lie submerged beneath the lake. The
5-km-wide Volcano Island in north-central Lake Taal is the location of all
historical eruptions. The island is composed of coalescing small
stratovolcanoes, tuff rings, and scoria cones that have grown about 25% in
area during historical time. Powerful pyroclastic flows and surges from
historical eruptions have caused many fatalities.



Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)
https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!flVDFiNIpMqJUBaq_LWu1117zhQK5U3XLcHpT-8MNomrp6ilCirR9K7dhlWVvzpg39EvSbDkiE4RFbzZ$ 
<https://urldefense.com/v3/__http://www.phivolcs.dost.gov.ph/__;!!IKRxdwAv5BmarQ!f0hNGom0WJzNKZ4kr9BV_8ldu62cCG6yt4qyNBrgqJXQF8z9KxI27F1MwGnTeAyVxgw9NdEg4VY$>



7-7-7-7-7-7-7-7-7-7-7-7-7-7



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End of Volcano Digest - 8 Aug 2022 to 10 Aug 2022 (#2022-81)
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