[Vulkanen] The Ring of Fire #8: Het rommelt en borrelt

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Een van de grootste vulkanen in Rusland barst uit

Shiveluch, een van de meest actieve vulkanen op het Russische schiereiland Kamtsjatka, barstte donderdagavond uit. De uitbarsting zond aswolken tot 15 kilometer de lucht in en bedekte grote gebieden met stof.

De aswolk strekte zich uit over 250 kilometer in oostelijke richting en bedekte verschillende dorpen met grijs vulkanisch stof, aldus ambtenaren.

Ondertussen gaf het Instituut voor Vulkanologie en Seismologie het hoogste waarschuwingsniveau af voor de luchtvaart, volgens Russische persbureaus. Lokale autoriteiten adviseerden bewoners om binnen te blijven en sloten tijdelijk scholen in verschillende getroffen gemeenschappen.
Shiveluch bestaat uit twee delen: de 3.283 meter hoge Oude Shiveluch en de kleinere, zeer actieve Jonge Shiveluch.

Het Kamchatka schiereiland, dat zich uitstrekt tot in de Stille Oceaan op ongeveer 6.600 kilometer ten oosten van Moskou, is een van ’s werelds meest geconcentreerde gebieden van geothermische activiteit, met ongeveer 30 actieve vulkanen.

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Powerful eruptions at Lewotobi Laki-laki eject ash up to 16.7 km (55 000 feet) a.s.l., Indonesia

Powerful eruptive activity at Indonesia’s Lewotobi Laki-laki volcano continues after a series of high-level eruptions began on November 3, 2024, damaging over 2 300 homes and claiming lives of at least 9 people.

satellite image of ash produced by lewotobi volcano indonesia at 0440 utc on november 9 2024 f
Satellite image of ash produced by Lewotobi Laki-laki volcano in Indonesia at 04:40 UTC on November 9, 2024. Credit: JMA/Himwari-9, RAMMB/CIRA, The Watchers

Four days after the initial high-level eruption on November 3, activity at Lewotobi intensified again on November 7, with multiple high-level eruptions ejecting ash up to 16.7 km (55 000 feet) above sea level (a.s.l.)

A high-level eruption at 20:47 UTC on November 8 ejected ash to 15.2 km (50 000 feet) a.s.l. followed by another powerful explosion at 00:50 UTC on November 9, with the top of the ash cloud reaching 15.8 km (52 000 feet) a.s.l., according to the Darwin VAAC

The eruption on November 3 plunged nearby villages into darkness as lava bombs and volcanic debris rained down up to 4 km (2.1 miles) from the crater, damaging over 2 300 homes, claiming the lives of 9 people and leading to power outages. Authorities have declared a state of emergency, extending assistance to over 10 000 affected residents.

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Wetenschappers verwachten uitbarsting van onderzeese vulkaan in 2025

Negen jaar nadat Amerikaanse wetenschappers een uitbarsting van de onderzeese vulkaan Axial Seamount wisten te voorspellen, denken ze dat er volgend jaar een nieuwe uitbarsting volgt.

Geofysicus William Chadwick verklaarde eerder deze maand tijdens een bijeenkomst van de American Geophysical Union in Washington DC dat metingen van de druk op de zeebodem wijzen op een uitbarsting in 2025. Uit de meetresultaten blijkt dat er zich steeds meer magma heeft verzameld onder de zeebodem, wat de druk opvoert. Er is ook sprake van toegenomen seismische activiteit.

Dit archiefbeeld van een onderzeese vulkaan in Japan uit 2013 geeft een idee van hoe het er kan uitzien als zo’n vulkaan uitbarst.

Axial Seamount is een onderzeese vulkaan in het noordoostelijk deel van de Grote Oceaan en bevindt zich meer dan 400 kilometer voor de kust van Oregon. Er is de voorbije jaren veel meetapparatuur aangebracht. In 2015 wisten wetenschappers al ruim op voorhand een vulkaanuitbarsting te voorspellen, wat best uitzonderlijk is.

“We hebben geen glazen bol”, zegt de Italiaanse vulkanoloog Valerio Acocella aan Sciencenews. “Voorspellingen zijn gebaseerd op de verwachting dat een vulkaan kan uitbarsten wanneer bepaalde activiteiten en metingen worden waargenomen.” Het gaat om het herkennen van patronen, beaamt geofysicus Michael Poland van Cascades Volcano Observatory. “Maar we kunnen niet uitsluiten dat een vulkaan een patroon volgt dat we nog niet eerder hebben waargenomen.

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Mount Semeru Erupts Ten Times, Ash Reaches 1,200 Meters

TEMPO.CO, Lumajang - Mount Semeru in East Java experienced a series of ten eruptions on Thursday, January 2, 2025. The resulting ash column reached a height of 1,200 meters above the summit or 4,876 meters above sea level.

Liswanto, an officer at the Semeru Volcano Observation Post (PGA) in Lumajang, reported that the ash column was observed to be white to gray in color, with a moderate intensity directed towards the north.

Seismograph recordings from the monitoring post located on Mount Sawur in Sumber Wuluh Village, Candipuro District, Lumajang Regency, East Java, documented ten eruptions from early Thursday morning through the afternoon.

The most intense volcanic activity occurred at 00:57, 02:41, 05:05, 07:57, 08:51, 10:02, 11:18, 11:22, 11:25, and 11:37. The peak intensity was monitored between 11:00 and 12:00, during which Semeru erupted four times within approximately one hour. However, visual observation of the eruptions was hampered by thick cloud cover.

Liswanto confirmed that Mount Semeru's activity level remains at Alert Level II (Waspada). The Mount Semeru monitoring post also recorded various seismic activity in the 24 hours leading up to early Thursday morning.

This included 34 eruption earthquakes with amplitudes ranging from 10-23 mm and durations of 53-145 seconds; one avalanche earthquake with an amplitude of 3 mm and a duration of 50 seconds; seven "gust" earthquakes with amplitudes of 2-8 mm and durations of 34-62 seconds; three distant tectonic earthquakes with amplitudes of 9-20 mm, S-P waves of 22-26 seconds, and durations of 52-86 seconds; and one flood vibration earthquake with an amplitude of 10 mm and a duration of 4,950 seconds.

Given Mount Semeru's current Level II (Alert) status, the Center for Volcanology and Geological Disaster Mitigation (PVMBG) has issued several recommendations to local residents. These include avoiding all activity within an 8 km radius of the peak (eruption epicenter) in the southeast sector along Besuk Kobokan.

Outside of this 8 km radius, the public is advised to refrain from any activity within 500 meters of riverbanks along Besuk Kobokan due to the potential for hot clouds and lava flows extending up to 13 km from the peak.

The PVMBG also urges residents to avoid any activity within a 3 km radius of the crater or peak of Mount Semeru due to the risk of ejected incandescent rocks. Furthermore, the public is urged to remain vigilant regarding the potential for hot clouds, lava avalanches, and lava flows along rivers or valleys originating from the mountain's peak, particularly along Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat, as well as the potential for lava flows in smaller rivers that are tributaries of Besuk Kobokan.

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Strong explosive eruption at Ibu volcano, Indonesia

A strong eruption at Ibu volcano produced lava fountains reaching hundreds of meters and ash plumes rising to 5.5 km (18 000 feet) a.s.l., on January 11, 2025, accompanied by volcanic lightning and active lava dome growth. The Aviation Color Code remains at Orange following an upgrade to Red on January 11 for a brief time.

The explosive event on January 11 began with intense activity marked by towering lava fountains that created dome-shaped fire plumes and reached several hundred meters into the atmosphere.

The eruption released dense ash clouds with columns rising to an altitude of approximately 5.5 km (18 000 feet). The ash emissions moved westward and spread over a large area.

The eruption also generated volcanic lightning which is often referred to as “dirty thunderstorms,” caused by collisions of charged particles like ash and lava fragments.

The ongoing activity at the volcano’s summit continues to extrude viscous magma and is contributing to the growth of a glowing lava dome. The process has resulted in the advancement of lava flows on the northern flank of the stratovolcano.

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Thousands flee as Indonesia raises Ibu volcano alert to highest level

Increased volcanic activity at Indonesia’s Ibu volcano prompted authorities to raise the Alert Level to 4 on January 15, 2025, and issue evacuation orders for some 3 000 people living in 6 villages near the volcano.

The Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG), Indonesia’s Center for Volcanology and Geological Hazard Mitigation, increased the Alert Level for Ibu volcano to IV (the highest) on January 15, following a series of eruptions with dense ash emissions up to 4 km (13 100 feet) above the summit and a 500 m (1 640 feet) long pyroclastic flow on January 15.

As a result, around 3 000 people living in 6 villages near Ibu were ordered to evacuate.

By Thursday morning, January 16, 517 residents from the village nearest to the volcano had been evacuated, with the remaining residents scheduled to be relocated later in the afternoon.

“The evacuation shelters have been prepared by the local administration, and today a full evacuation will be carried out for all residents in six villages,” said Irfan Idrus, a spokesman for the local disaster management agency.

Idrus added that evacuations began on Wednesday at 18:00 LT (11:00 GMT) but were delayed due to administrative and logistical issues. In addition, rainfall affecting the area since Thursday morning has further hampered the process.

Residents, visitors, and tourists are advised to avoid activities, climbing, or approaching Ibu within a 5 km (3.1 miles) radius and a 6 km (3.7 miles) sector extending from the crater opening in the northern part of the active crater.

If ashfall occurs, individuals outdoors are advised to use masks for nose and mouth protection and wear eye protection, such as glasses.

Residents beyond the 5 km radius and outside the 6 km sector are urged to remain vigilant and follow directives from the Regional Government.

Communities near Mount Ibu should be aware of the potential for lava flows in rivers originating from the peak, particularly during heavy rainfall.

Residents are urged to remain calm, avoid misinformation regarding the eruption, and follow guidance from the North Maluku Provincial BPBD, the West Halmahera Regency BPBD, and the Center for Volcanology and Geological Disaster Mitigation, Geological Agency in Bandung.

Ibu Volcano has been erupting since 2008. Its activity involves frequent ash emissions, dome growth within its inner crater, and occasional lava flows.

The volcano’s eruptive history includes activity in 1998 and 2008 marked by ash emissions and lava dome formation.

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Massive underground aquifer discovered beneath Oregon’s Cascade Range

Scientists from the University of Oregon have discovered a vast underground aquifer beneath Oregon’s Cascade Range, storing at least 81 km3 (19.4 mi3) of water — almost three times the maximum capacity of Lake Mead. The research detailing the findings was published on January 13, 2025, reshaping the understanding of the region’s water resources and volcanic hazards.

A newly discovered underground aquifer beneath Oregon’s Cascade Range holds at least 81 km3 (19.4 mi3) of water which is nearly 3 times the capacity of Lake Mead – currently overdrawn reservoir along the Colorado River that supplies water to California, Arizona, and Nevada, and greater than half the volume of Lake Tahoe.

Researchers say this vast water reservoir stored within volcanic rock has implications for regional water resources and volcanic hazards.

“It is a continental-size lake stored in the rocks at the top of the mountains, like a big water tower,” Leif Karlstrom, a geophysicist from the University of Oregon who led the study said. “That there are similar large volcanic aquifers north of the Columbia Gorge and near Mount Shasta likely make the Cascade Range the largest aquifer of its kind in the world.”

The study indicates that this aquifer plays an important role in regional hydrology and volcanic activity.

The Cascade Range has been shaped by volcanic processes over millions of years and created porous lava flows that allow deep water circulation.

Researchers believe this water storage system could serve as a long-term reservoir and mitigate the effects of climate change on water availability. Many communities in Oregon depend on water from the Cascades including the McKenzie River which supplies drinking water to Eugene.

Further analysis of geological formations suggests that similar aquifers may exist in other volcanic regions. Scientists have used drill samples and geophysical imaging techniques to map the structure of the subsurface water network and reveal extensive underground channels capable of sustaining long-term water reserves.

The presence of such a large underground water system also has implications for volcanic hazards. Eruptions can become more explosive when magma interacts with groundwater and increases the risks posed by Cascade Range volcanoes.

“The movement of water and the hazards posed by volcanoes are linked together,” Gordon Grant, co-author of the study from the United States (U.S.) Forest Service stated.

Geological models indicate that water stored within volcanic rocks could alter the stability of magma chambers. The interaction between hot magma and pressurized water has been associated with explosive volcanic activity in the past.

Researchers focus on the need for continued monitoring of both water levels and seismic activity in the Cascade region to assess potential risks.

The discovery of this aquifer could provide an important buffer against water shortages with increasing droughts and declining snowpack levels. Scientists estimate that the aquifer may take decades to fully recharge through natural processes and this makes careful management essential.

Hydrologists and policymakers are now evaluating how best to utilize this newly discovered water source. Potential applications include augmenting municipal water supplies, supporting agricultural irrigation, and maintaining ecosystem stability.

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Earthquake swarm in Taupo Volcanic Zone, New Zealand

A swarm of over 50 earthquakes has been recorded in the geothermal area, north of Taupo volcano, since 18:00 LT (05:00 UTC) on Thursday, January 30, 2025. The strongest earthquake was M2.9, with many earthquakes being reported as ‘unnoticeable’ or ‘weak’ by GeoNet.

A swarm of over 50 earthquakes has been detected in the geothermal area, north of Taupo, since 05:00 UTC on January 30, with the strongest earthquake being M2.9.

GeoNet reported that many earthquakes were found to be ‘unnoticeable’ or ‘weak’ by the automated system. Some residents in Taupo have felt the shaking despite the classification. The sequence is expected to diminish over the coming days though monitoring continues.

The Taupo area, situated within the Taupo Volcanic Zone (TVZ), frequently experiences earthquake swarms because of its complex geological setting.

The ongoing swarm consists of relatively small earthquakes with magnitudes below 2.9 though one event, an M2.9, has generated over 1 000 felt reports. Most of the tremors have been shallow and are intensifying the likelihood of being noticed by people in the vicinity.

A GeoNet earthquake map shows the distribution, with black dots representing the latest earthquakes since January 30, contrasting with red dots indicating those from the past year.

Unlike traditional earthquake sequences that feature a primary large earthquake followed by aftershocks, earthquake swarms consist of multiple small tremors occurring in a concentrated area over hours, days, or weeks. Such swarms are common across New Zealand in the TVZ where geothermal and magmatic activity influence seismic events.

Fluids, such as water or gases from deeper magma sources can migrate along faults and fractures in the crust. The process reduces friction along pre-existing faults and allows slippage that results in seismic activity. In the TVZ, the combination of geothermal activity and deep-seated magmatic processes contributes to frequent swarms.

While the region is home to Taupō, one of the world’s most active rhyolitic caldera volcanoes, there is no current evidence linking this earthquake swarm to increased volcanic activity. Earthquakes in the area often occur because of geothermal and tectonic interactions rather than magmatic intrusion.

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Japan maakt zich klaar voor mogelijke uitbarsting van vulkaan Mount Fuji
De Japanse overheid maakt nieuwe richtlijnen bekend over hoe de bevolking zich moet voorbereiden op een mogelijke uitbarsting van Mount Fuji, de beroemde vulkaan bij Tokio. Hoewel er geen directe tekenen zijn dat de vulkaan op korte termijn zal uitbarsten, blijft deze actief. Experts benadrukken dat vooruitdenken en voorbereiding moeten om grote schade en chaos te voorkomen.

Mount Fuji, de meest iconische vulkaan van Japan, is al 318 jaar in rust. De laatste uitbarsting vond plaats in 1707 en had destijds een grote impact op het land. Experts waarschuwen voor de mogelijkheid van een nieuwe explosieve uitbarsting, vergelijkbaar met 300 jaar geleden. Dat kan uitgebreide schade veroorzaken, vooral in stedelijke gebieden, zoals Tokio.

Volgens Toshitsugu Fujii, professor aan de Universiteit van Tokio, heeft het Japanse rampenplan rekening gehouden met een mogelijk worstcasescenario. “Bij een grote uitbarsting verwachten we dat er tot 1,7 miljard kubieke meter vulkanische as vrijkomt, waarvan ongeveer 490 miljoen kubieke meter zich zal ophopen op wegen, gebouwen en andere infrastructuur”, zei hij tijdens een persconferentie op 21 maart.

Hij waarschuwt dat een dergelijke ophoping niet alleen logistieke problemen zou veroorzaken, maar ook een groot risico voor de veiligheid van mensen.

Richtlijnen
De richtlijnen van de Japanse autoriteiten benadrukken dat burgers tijdens een uitbarsting zoveel mogelijk thuis moeten blijven. Het advies is om een noodvoorraad van belangrijke goederen aan te leggen die minimaal twee weken meegaat.

Evacuatie kan echter noodzakelijk worden als meer dan 30 centimeter vulkanische as zich ophoopt. Dit kan leiden tot het instortingsgevaar van houten huizen met een lage draagkracht. “Een uitbarsting betekent niet alleen asregen, maar ook mogelijke verstoring van elektriciteit, waterleidingnetten en transport", vervolgt Fujii. De overheid is voorbereid is om op grote schaal hulp te bieden, mits inwoners tijdig de basisrichtlijnen volgen.

Gevolgen
Zelfs een kleine hoeveelheid vulkanische as kan grote verstoringen veroorzaken. Dit begint bij het transport: treinen zouden kunnen stoppen met rijden en wegen kunnen onbruikbaar worden wanneer de as zich ophoopt, vooral in combinatie met regen. Daarnaast kan de ophoping leiden tot stroomstoringen, wat het leven in stedelijke gebieden volledig ontregelt.

De lucht zou bedekt worden met zwarte vulkanische as, waardoor stedelijke gebieden zelfs overdag in het donker zouden zitten, volgens de regering.

De economische impact van een grote Mount Fuji-uitbarsting wordt geschat op maximaal 2,5 triljoen yen (ongeveer 15,4 miljard euro). Naast directe schade aan wegen en gebouwen, zouden distributiesystemen en logistiek ernstig verstoord worden, waardoor het verkrijgen van essenti�le goederen moeilijk wordt.