Seismic Activity In Öræfajökull Still Going Strong

Seismic activity in Öræfajökull volcano continues. This month, fourteen earthquakes measuring over 1.2 have been detected.

An uncertainty level was declared in October and has yet not been lifted. Seismic activity has increased steadily since autumn 2016 and in the past few months it’s been stronger than since measurements began four decades ago.

Geophysicist Páll Einarsson says in today’s issue of Morgunblaðið that these earthquakes “are telling us that there’s plenty of reason to monitor the course of events carefully.”

Swarm Of Earthquakes Hits North Iceland

Almost thirty earthquakes occurred in North Iceland and the ocean north of Iceland last night. The largest earthquake of the swarm occcured at 2.30 AM at a magnitude of 3.0. Its origins were around 20 km North East of Siglufjörður.

The swarm began at around 00.30 last night and most of them were at a magnitude of between 1.0 and 2.0. An earthquake of 2.8 occurred North East of Grímsey.

The Iceland Met Office sees no cause for concern but is carefully monitoring events.

Mount Etna: Europe’s Biggest Volcano ‘Sliding Towards The Sea’

The most active volcano in Europe is slowly sliding into the sea, according to new research.

Mount Etna – located on the Italian island of Sicily – is edging towards the Mediterranean at a rate of around 14mm per year.

While its movement may seem too slow to cause any concern, scientists studying the geology of the volcano have said the situation will require careful monitoring.

“I would say there is currently no cause for alarm, but it is something we need to keep an eye on, especially to see if there is an acceleration in this motion,” lead author Dr John Murray told the BBC .

This is the first time downward “basement sliding” of an entire active volcano has been directly observed.

However, studies of extinct volcanoes suggest this phenomenon can lead to “devastating” collapse of their downslope sides, resulting in landslides.

Dr Murray, who has studied Mount Etna for nearly 40 years, has worked with his team to produce lab simulations of how such activity takes place.

They concluded that despite its instability, any threat posed by the volcano’s downward trajectory will likely not arise for thousands of years.

A more pressing concern could be the disruptive effect the sliding activity will have on the monitoring of future volcanic eruptions.

Mount Etna was first recorded erupting in 1500 BC, and since then it has erupted around 200 times, with a burst of activity in recent decades.

The last such event came in 2017, when several tourists and a BBC crew were injured after being “pelted with boiling rocks and steam”.

Researchers will need to account for their new measurements when conducting eruption forecasting for Mount Etna, as the deformation caused by a lava bulge in the mountain could be impacted by its downward movement.

The study, carried out by Dr Murray and his collaborators over the course of 11 years, was published in the journal Bulletin of Volcanology.

They arrived at their conclusions using data collected with a network of precise GPS stations around the volcano that monitor tiny changes in its behaviour.

Mount Etna is moving down a very gentle slope due to its position on a base of relatively weak, loose sediments.

While the data showed the mountain was moving in an east-south-east direction, towards the coastal town of Giarre, Dr Murray confirmed there was no need for local people to be concerned.

“The thing to watch I guess is if in 10 years’ time the rate of movement has doubled – that would be a warning,” he said.

“If it’s halved, I’d say there really is nothing to worry about.”

Newly Discovered Hot Magma Plume Beneath Yellowstone Volcano Stretches To Mexico

New evidence on Yellowstone’s volcanic activity might shed light on the long-debated theory on the presence of magma plume beneath the national park.

The Yellowstone caldera is a complex system of rock formations that sprung after a series of volcanic eruptions some 630,000 million years ago. This is the widely accepted theory, although there are some scientists who argue that the national park sits right on top of a “hot spot.”

Results of the investigation conducted by Peter Nelson and Stephen Grand from the University of Texas’ Jackson School of Geosciences supports the latter theory suggesting a massive magma plume beneath the park’s surface. This plume, which is the technical word for a magma foundation, appears to extend as far as Mexico.

In a geographic sense, a plume is an abnormality that exists when the earth’s core rises through the mantle forming what it appears to be a foundation of hot magma.

The study, which was published in Nature Geoscience, reported that the probability of a magma plume underneath Yellowstone could explain the heat that influences ground activities such as the Boiling River. This latest claim debunks earlier explanations that the heat source is a by-product of lithospheric movements.

Nelson and Grand’s team gathered seismic data using EarthScope’s USArray, which showed a “long, thin, sloping zone” that measured about 72 kilometers long and 55 kilometers wide. Because seismic patterns travel slower in this region of the mantle, it is understandable that it can be up to 800 degrees Celsius higher than its surrounding areas.

The emerging image revealed a 350-kilometer cylinder formation that runs all the way to the California-Mexico border.

Yellowstone is not the only one with suspected magma plume. In fact, the volcanic island of Hawaii is home to a chain of active plumes that date back millions of years ago.

In the case of Hawaii, plumes are formed when the ocean plate moves beneath land masses in a process called subduction. Rocks could get in the way during the process, then forming the plumes which are fixated on earth.

“There are many suspected plumes, or hot spots, around the Earth. Yellowstone is one of them, but it’s a bit more complex,” said Michael Poland, a scientist at the Yellowstone Volcano Observatory.

According to Polan, although the science of plumes seems complex, it has always been there posing itself as a natural geographic occurrence.

“[Plumes have] no impact on our understanding of how Yellowstone works in terms of eruptive cycles, just their driving forces. It doesn’t change our perception of volcanic activity at all,” Poland explained.

Volcano In Indonesia Belches Toxic Fumes That Poison 30 People

Thirty people were treated for sulfur gas poisoning after Mount Ijen in eastern Java belched toxic fumes from its crater, Indonesia’s disaster agency said Thursday.

Spokesman Sutopo Purwo Nugroho said more than 170 residents of several villages on the volcano’s slopes had to flee.

He said some suffered shortness of breath and vomiting following the steam and gas-based eruption about 7:15 p.m. on Wednesday.

The mountain is known for its stunning sulfur lake and night-time sulfur mining involving dangerous and backbreaking work by low paid laborers.

Sutopo said Ijen’s summit is now temporarily off limits to activities but the volcano’s overall status remains normal.

Indonesia, which straddles the seismically volatile Pacific “Ring of Fire,” has more than 120 active volcanoes.

Volcano Watch: Kilauea Volcano’s Summit Eruption Is Now A Decade Old

A little more than 10 years ago, conditions around Kilauea Volcano’s summit were much different than today. The caldera floor was open to the public, and the air above it was normally clear. Halema‘uma‘u was an impressive sight, but peacefully in repose.

That quiet phase at Kilauea’s summit ended abruptly in 2008, ushering in a new era of lava lake activity that continues today.

Let’s review the past decade of this summit eruption.

After several months of increased seismic tremor and gas emissions, there was a small explosion in Halema‘uma‘u on March 19, 2008. The explosion marked the opening of a new crater, informally called the “Overlook crater.” During the remainder of 2008, several more explosions deposited spatter around Halema‘uma‘u, and the Overlook crater enlarged through collapses of its rim.

During 2009, small lava lakes were sometimes active deep within the Overlook crater. But since early 2010, the lava lake has been continuously present, steadily growing and rising higher.

The rise was interrupted March 5, 2011, when the lava lake briefly drained away because of the Kamoamoa eruption on Kilauea’s East Rift Zone.

The lava lake stabilized in 2012, rose to a higher level in 2013 and remained stable in 2014 and early 2015. In April 2015, the lava lake rose abruptly and briefly overflowed, spilling lava onto the floor of Halema‘uma‘u. High lake levels in 2016 allowed lava to be frequently observed from public viewing areas in Hawaii Volcanoes National Park, but a gradual drop in 2017 has made direct viewing of the lake less common during the past year.

The lava lake activity in 2018 is similar to that during the previous several years — relatively steady — and there are no signs that the summit eruption is slowing down.

Halema‘uma‘u now hosts one of the two largest lava lakes on Earth. It is likely the largest, but this cannot be said with complete certainty, as regular measurements are not available from the closest contender — Nyiragongo volcano in the Democratic Republic of the Congo.

Most persistent lava lakes are difficult to access, either because of geographic location (for example, Erebus in Antarctica) or political instability (for example, Nyiragongo). The size and accessibility of the Halema‘uma‘u lava lake, as well as the existing network of monitoring instruments, make it one of the premier locations to study lava lake behavior.

USGS Hawaiian Volcano Observatory scientists, along with collaborators from other institutions, are engaged in research to understand how the lava lake works and what it can tell us about the behavior and hazards of Kilauea.

For instance, we learned that the lake rises and falls in concert with changes in summit ground tilt. This tells us that the lake responds to the pressure of the magma chamber, so the lake level can be used like a pressure gauge.

The lake also fluctuates in concert with the lava pond at Pu‘u ‘O‘o on Kilauea’s East Rift Zone, illustrating the hydraulic connection between the two eruption sites. Lava chemistry at the two sites also is similar, adding further evidence of a close connection.

Another important finding deals with the nature of small explosions that occur at the lava lake from time to time.

HVO webcams revealed that the explosions are triggered by rockfalls from the Overlook crater rim impacting the lake surface. This observation is further evidence that the lava lake is very gassy, akin to lava foam. Rocks falling into this gas-rich, frothy lava triggers violent releases of gas that send spatter flying.

While the summit eruption has benefited science, it comes with many challenges, including persistent volcanic air pollution (vog) resulting from elevated sulfur dioxide gas emissions from the lava lake. Vog impacts the entire state at times, but the Ka‘u and Kona districts on the Island of Hawaii have been particularly hard hit.

Kilauea has a history of long-lasting summit eruptions, but it remains to be seen if the current eruption will go on for another decade. The past few years of stable activity suggest the summit lava lake is likely to continue into the near future.

However long it lasts, HVO will continue to study this awe-inspiring, unique feature to discover what more it can reveal about the volcano.

Volcano activity updates

This past week, Kilauea Volcano’s summit lava lake level fluctuated with summit inflation and deflation, ranging about 30.5-40.5 m (100-133 ft) below the vent rim. On the East Rift Zone, the 61g lava flow remained active downslope of Pu‘u ‘O‘o, with scattered breakouts on the upper part of the flow field and on Pulama pali, but no ocean entry. The 61g flows do not pose an immediate threat to nearby communities.

Mauna Loa is not erupting. Rates of deformation and seismicity have not changed significantly in the past week, persisting at above-long-term background levels. Sixteen microearthquakes (magnitudes less than 2) were located beneath the summit caldera, upper Southwest Rift Zone and western flank of the volcano at depths of 0-5 km (0-3 mi). GPS and InSAR measurements continue to show slow deformation related to inflation of a magma reservoir beneath the summit and upper Southwest Rift Zone. No significant changes in volcanic gas emissions were measured.

No earthquakes were reported felt in the Hawaiian Islands this past week.

Volcanic Activity Threatens Families Again On Ambae Island In Vanuatu

Volcanic activity on Vanuatu’s Ambae Island has picked up again over the last few days, with fresh ash fall reported across the island’s west and south.

Communities in the western and southern parts of Ambae are suffering badly from thick periodic ash fall which threaten their health, animals and vegetation.

The entire island was evacuated late last year when the volcano at the island’s centre erupted, blanketing the island in ash, suffocating crops and contaminating water sources.

The only population returned to their homes when the eruption settled down after a month, but on Sunday night the volcano’s alert level was raised from level 2 to 3, a “state of minor eruption.”

The Geohazards Department’s Melinda Aru said the volcano was showing increased activity and an exclusion zone had been extended to three km around the crater lake.

“We’ve got a few reports coming from Ambae concerning ash fall on the west, southwest and northwest as of last week until Sunday. We still have reports from Ambae concerning ash fall.”

Melinda Aru said the chance of the eruption increasing to the level seen in October last year was highly unlikely.

Reports on the Vanuatu Daily Post website on Monday said that people may need to shelter livestock and water tanks as the Lombenben volcano continues to emit ash.

The Vanuatu Meteorology and Geo-hazards Department still grades the Ambae volcano at major unrest stage.

Destruction caused by the ash fall in affected areas is described as literally similar to a cyclone wiping out trees and crops.

Its weight caused plants and crops in the gardens like banana, cassava and cabbages to collapse.

Destruction done by volcanic ash on people, plants and crops depend largely on its thickness. Though it may causes health problems to livestock and human such as skin irritation and eye problem, volcanic ash can make the soil fertile.

Responsible authorities have warned that everyone, particularly children should be protected from the volcano’s ash and poisonous gases that poses a health risk.

The Vanuatu Red Cross Society (RCS) said it was working to establish a sub-branch in west Ambae to support communities during disasters.