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Eruption With Lava Flow At Kilauea Volcano In Hawai’i

Lava fountains from the bottom of the deep pit crater in Kilauea’s Halema’uma crater, from the west rim of the collapse crater (image: HVO)

A new eruption started at Kilauea volcano in the evening of 20 Dec in Hawaii (local time). The volcano observatory reported:

“Shortly after approximately 9:30 p.m. HST, the USGS Hawaiian Volcano Observatory (HVO) detected glow within Halemaʻumaʻu crater at the summit of Kīlauea Volcano. An eruption has commenced within Kīlauea’s summit caldera. The situation is rapidly evolving and HVO will issue another statement when more information is available.”

During the past weeks, earthquakes had been more frequent under the caldera and the upper rift zone. They likely reflected magma intrusions at shallow level.

Shortly after the new eruption, observed less than two hours ago, a magnitude 4.3 quake struck the southern flank of the volcano, about 10 miles west of Kalapana. This quake might be related as a response to the new eruption, probably causing a small southwards movement of the southern flank of Kilauea, acting as adjustment for the additional space needed of the magma intrusion in the summit area.

Courtesy of volcanodiscovery.com

https://tinyurl.com/jc6svx3

New eruption at Piton de la Fournaise Volcano in (La Réunion, France), Indian Ocean

New eruption of Piton de la Fournaise volcano this morning (image: OVPF/IPGP)

A new eruption started at the volcano this morning. At around 2.28 am local time, the seismic network of the observatory detected a seismic crisis, typical sign of magma pushing its way towards the surface. Other instruments detected rapid local ground deformation, another tell-tale sign of an impending eruption.

At around 4.40 am, volcanic tremor was recorded by the instruments, reflecting now a continuous flow of magma towards the surface. The first lava probably came out shortly after, at around 4.50-4.55 am. 3 fissures opened at altitude between 2190 and 2300 m on the southwestern flank of the summit cone and started to erupt small lava fountains, about 15 m tall, from a chain of vents.

The eruption has been producing multiple lava flows that started to descend slowly on the flanks. By the time of first visual observations made by scientists on an aerial survey a few hours later, the most advanced lava flow front had descended to 2120 m altitude. Given this rather low rate of advance and low height of lava fountains, the discharge rate of this eruption seems rather low compared to most previous eruptions of Piton de la Fournaise.

Today’s eruption marks the third of the volcano in 2020, after eruptions in February and April this year. It followed a period of frequent seismic unrest, last detected during the morning of 4 Dec. These preceding periods likely reflect intrusions and the recharging of shallow magma reservoirs, events that often build up to eruptions like the current one. Piton de la Fournaise is one of the world’s most active volcanoes and typically erupts several times each year.

Courtesy of volcanodiscovery.com

https://tinyurl.com/y3kjz7ps

Incandescent Avalanches at Sinabung Volcano in Sumatra, Indonesia

Incandescent avalanches from Sinabung volcano on 28 October (image: Firdaus Surbakti/twitter)

The activity of the volcano has remained essentially unchanged and characterized by pyroclastic flows over the past days.

Courtesy of volcanodiscovery.com

https://tinyurl.com/y5d23s6f

Taal volcano update: Eruption alert as 116 earthquakes hit Philippines volcano overnight #earthquake TaalVolcano #philippines

Taal volcano update: Erupting Philippines volcano

The Philippines volcano is showing signs of volcanic activity (Image: GETTY/UNOCHA)

The volcano alert level for Taal is 3, meaning geologists are braced for an eruption in a matter of weeks. According to the Philippine Institute of Volcanology and Seismology (PHIVOLCS), Alert level 3 represents a high level of volcanic unrest.

The alert is marked by sustained seismic activity, plumes of smoke belching from Taal as well as toxic gas emissions and the movement of magma underground.

On Friday, PHIVOLCS warned of 116 tremors were detected around Taal volcano in the 24 hours since midnight GMT (8am local time).

The Taal Volcano Network recorded, in addition, two low-frequency earthquakes, which could be a sign of molten rock entering the volcano.

PHIVOLCS warned: “These earthquakes signify magmatic activity beneath the Taal edifice that could lead to eruptive activity at the Main Crater.”

The agency warned the residents of Luzon Island to stay clear of the volcano in a 4.3-mile-wide radius.

Access to the danger zone is restricted in parts of Agoncillo, Laurel and Batangas.

According to the UN Office for the Coordination of Humanitarian Affairs, about 486,000 people have been affected by the erupting volcano since January 12.

On Friday, the fiery mountain sitting in the middle of Taal Lake was coughing up plumes of dirty steam and smoke.

The volcanic plumes were seen reaching heights between 1,640ft and 2,296ft, drifting in a southwest direction.

At the same time, PHIVOLCS said emissions of toxic sulphur dioxide (SO2) have dropped below instrumental detection.

Although eruptive activity has ceased since two blasts tore through Taal on January 12 and January 13 respectively, the volcano is still at risk of erupting.

Since January 12, Philippine Seismic Network (PSN) has recorded a total of 763 volcanic earthquakes around Taal.

The seismic activity was marked by fissures splitting the ground open on the southern parts of Luzon Island.

At least 177 of the quakes peaked at magnitudes between 1.2 and magnitude 4.2.

Between January 29 and January 31, the PSN recorded seven quakes between magnitude 1.7 and magnitude 2.5.

PHIVOLCS warned on Friday of more earthquakes, steam-driven eruptions, ashfall and lethal gases venting from the volcano.

The agency said: “DOST-PHIVOLCS recommends that entry into the Taal Volcano Island as well as into areas over Taal Lake and communities west of the island within a 7km radius from the Main Crater must be strictly prohibited.

“Local government units are advised to assess areas outside the 7km radius for damages and road accessibilities and to strengthen preparedness, contingency and communication measures in case of renewed unrest.

“People are also advised to observe precautions due to ground displacement across fissures, frequent ashfall and minor earthquakes.”

Riverside communities are at risk of lahars – fast-moving streams of mud, debris and volcanic ash mixed with water, particularly after heavy rainfall.

PHIVOLCS said: “Civil aviation authorities must advise pilots to avoid flying close to the volcano as airborne ash and ballistic fragments from sudden explosions and wind-remobilized ash may pose hazards to aircrafts.

“DOST-PHIVOLCS is closely monitoring Taal Volcano’s activity and any new significant development will be immediately communicated to all stakeholders.”

Courtesy of express.co.uk

https://tinyurl.com/s64u7gj

Yellow Alert issued due to unusual rapid inflation beneath Mt. Thorbjorn on Reykjanes peninsula, Iceland #YellowAlert #MountThorbjorn #reykjanes #iceland

The map shows recent earthquake activity in the area. Mt. Thorbjorn is situated just above the black triangle which indicates one of IMO’s seismographs.

Inflation has been detected in the last few days. An earthquake swarm has been ongoing during the same period. A state of uncertainty has been declared. The aviation color code has been raised to yellow for Reykjanes.

An inflation has been detected since January 21st and is centred just west of Mt. Thorbjorn on Reykjanes peninsula. The inflation is unusually rapid, around 3-4 mm per day and has accumulated to 2 cm to date. It has been detected both on continuous GPS stations and in InSAR images. The inflation is most likely a sign of magma accumulation at a depth of just a few km. If magma accumulation is causing the inflation, the accumulation is very small, with the first volume estimate is around 1 million cubic meters (0,001 km3). This is the conclusion of a meeting held with the Scientific council of the Civil Protection at the IMO this morning.

Accurate measurements of crustal deformation on Reykjanes peninsula span approx. three decades. During this period no comparable signal has been measured. This is unusual for this period. An earthquake swarm has been ongoing, since January 21st, alongside the deformation signal just east of the inflation centre (northeast of Grindavík). The largest earthquakes occurred on January 22nd and were of M3,7 and 3,6. They were felt widely on the Reykjanes peninsula and all the way to Borgarnes region. The earthquake swarm is currently in decline. Swarms like this are common and not unusual by itself in the area. The fact that an inflation is occurring alongside the earthquake swarm is a cause for concern and closer monitoring.

The inflation is centred within an active volcanic zone

The inflation is occurring on plate boundaries and within the volcanic system of Svartsengi which is either considered a separate system or part of the Reykjanes volcanic system. The last known eruption was during Reykjanes fires, which occurred between 1210-1240 AD. Within that period a several eruptions occurred within that system, thereof there were three eruptions in Svartsengi system. The eruptions were effusive (non-explosive) fissure eruptions erupting on 1-10 km long fissures. No explosive eruptions are known from this system. The largest eruption in the swarm, from 13th century, formed Arnarseturshraun lava (estimated 0,3 km3 and 20 km2). Historically, the duration of these eruptions spans from a few days up to several weeks. Seismic activity is very common in this area and is linked to the plate boundaries, geothermal activity and possible magma intrusions. The largest earthquakes measured in this area are about M5.5.

Courtesy of en.vedur.is

https://tinyurl.com/yxygq4q4

Alert Level Raised To Orange At #Villarrica #Volcano In Central #Chile

Orange Alert Raised

Sernageomin has raised the alert level to Orange for the first time since 2015 due to escalating seismic tremor and a more turbulent lava lake (present in some form since late 2014). Although fairly unlikely, it is possible that a repeat of the March 2015 paroxysmal event could soon occur if there is a similar trend in activity. An exclusion zone of 2km is in force.

Courtesy of volcanodiscovery.com

https://tinyurl.com/y2y6kyqd

#YellowAlert Issued Due To Increased #SeismicActivity At #MaunaLoaVolcano In #Hawaii

Earthquakes under Manua Loa during the past week (image: HVO / USGS)

The alert level for the volcano has been raised to yellow two days ago. This doesn’t mean that an eruption is expected to occur in a near future, but acknowledges that the volcano is currently preparing itself for its next eruption, which will come, sooner or later, but currently without possibility to indicate a specific time frame.

The Hawaiian Volcano Observatory (HVO) reported that “for the past several months, earthquake and ground deformation rates at Mauna Loa Volcano have exceeded long term background levels. An eruption is not imminent and current rates are not cause for alarm. However, they do indicate changes in the shallow magma storage system at Mauna Loa.”

Courtesy of volcanodiscovery.com

https://tinyurl.com/y235wg4r

#Scientist warns #Russian #volcano could cause #Pompeii-scale #destruction

Volcano Alert

A volcano in the far eastern end of Russia that was thought to be extinct may now have awakened — and its eruption could be as severe as the one that destroyed the ancient Roman settlement of Pompeii, according to scientists.

In the fall of 2017, seismic activity was discovered underneath the Bolshaya Udina volcano, which was thought to be inactive for decades.

Since scientists began monitoring the area in 1961, only a single weak activity has been detected, according to the Russian Academy of Sciences (RAS).

After the initial activity was discovered, a detailed investigation was launched, which included four temporary seismic stations being placed near the volcano.

Over a two-month period from May to July 2018, 559 localized events were detected in the area of the volcanoes, according to a study that reported the investigation’s findings.

The continued activity led the study to conclude that the volcano may have to be reclassified as “active” given the possible presence of “magma intrusions with a high content of melts and fluids.”

In addition to those events, a 4.3-magnitude earthquake occurred under Udina in February — the strongest to be recorded in that area, according to RAS.

Long-dormant volcanoes pose great risks, according to Ivan Koulakov, the lead scientist investigating the volcano.

“When a volcano is silent for a long time, its first explosion can be catastrophic … Recall Pompeii,” Koulakov told RAS, referencing the ancient Roman settlement Pompeii that was totally destroyed by the eruption of Mount Vesuvius, which was dormant for thousands of years before.

Koulakov also explained that the eruption can have far-flung effects.

“A large amount of ash is thrown into the air, it is carried far away, and not only the surrounding settlements but also large territories all over the planet can suffer,” he said.

This ash can affect air travel and climate, according to CNN.

He pegged the chances of an eruption at 50 per cent.

“At any moment, an eruption can occur,” Koulakov told CNN.

Courtesy of globalnews.ca

https://tinyurl.com/y6ztrv9h