Lava Lake Visible Atop Hawaii’s Kilauea Volcano

The U.S. Geological Survey says a lake of lava has come into view atop Hawaii’s Kilauea volcano, and a burst of seismic activity has shaken the summit in recent days.

lava-lake

It’s the first time the lava lake has been visible since May 2015. It deflated Saturday, but it was expected to inflate again Sunday.
At least one earthquake was felt along with several smaller events, according to the Geological Survey.

Kilauea is one of the world’s most active volcanoes. A current lava flow into the Pacific Ocean has drawn thousands of visitors from around the world to Hawaii Volcanoes National Park.

Alert Heightened For Vanuatu Volcano

Vanuatu authorities have upgraded warnings around Ambae Volcano in northern Vanuatu.

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The country’s Geohazards Observatory has raised the alert to Level two on a scale of one to five which signifies the volcano is in a stage of major unrest.

The observatory says volcanic activity could increase at any time over the next few days.

It’s warned the local community, tourists and travel agencies to stay well away from the Manaro crater lakes to avoid the effects of volcanic gas, ash and other volcanic activity.

The Department of Meteorology and Geohazards is closely monitoring the volcano which last erupted in 2009.

Australian Scientists Uncover Evidence Of Super Eruptions 106 Million Years Ago

Australian scientists believe a super volcano active over 100 million years ago was so powerful it spewed tiny crystals across the breadth of the continent.

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It was not exactly the intended area of inquiry for researchers at Curtin University’s School of Mines but they recently stumbled upon the rather fascinating finding nonetheless.

Dr Milo Barham from the Department of Applied Geology led the study, which originally sought to examine the geology of the Nullarbor Plain in remote southeastern WA in order to study how the southern margin of the country evolved after separating from Antarctica.

However once they made the discovery of zircon crystals unlike any previously found in Western Australia, the research took a slightly new direction.

“It was somewhat fortuitous I suppose,” Dr Barham told news.com.au.

Researchers pulled up a vast amount of core material from the drilling to examine the sediment and study certain fossils. They also took a sample of earth to look at zircon crystal and study their chemistry and age to see what sort of rocks the crystals had been eroded from, Dr Barham recalled.

“And then suddenly there were these crystals that didn’t match any thing we know exists in Western Australia and we looked into it more carefully and we see that the chemistry and age match perfectly for what we’d expect for this volcanic region in eastern Australia.”

Using advanced geochemical fingerprinting of individual crystals as well as in-depth analysis of the sediments and their fossils, scientists were able to determine the crystals were the product of volcanic air fall — despite being 2300km from their original source on the other side of the country.

By looking at the age of the material and aspects of their chemistry “we could tell for definite that it came across from the volcanoes on the east coast”, Dr Barham said.

The findings from the dig point to the occurrence of super-eruptions over 100 million years ago.

According to the researchers at Curtin University, such explosive events would have had magnitudes tens to hundreds of times greater than anything in documented human history.

“Such distal projection of a unique volcanic mineral population demonstrates that super-eruptions were occurring in eastern Australia approximately 106 million years ago, during the breakup of the supercontinent Gondwana,” Dr Barham said.

We know about super eruptions in the more recent past. In the last few tens of thousands of years, or maybe a couple million years, he said.

“But trying to go back further to prove these super eruptions is really difficult because it’s very difficult to prove,” he added, because much of the geology from the time has been eroded away.

But given the use of the sophisticated fingerprinting technology, the team is highly confident about their conclusions.

Dr Barham says the findings, which were published in the journal Geology, shine a light on just how violent and volcanic the region was such a long time ago.

These massive eruptions “were not enough to cause any mass extinctions or anything like that but animals would’ve died as a result,” he said.

“It tells us about how violent the east coast of Australia would’ve been at that time.”

Mexico’s Popocatépetl Volcano Erupts 4 Times In Under 24 Hours

MEXICO CITY – Mexico’s National Center for Disaster Prevention said the Popocatépetl volcano has erupted multiple times, spewing ash and burning rocks into the air.

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The disaster prevention center, or CENAPRED, Monday afternoon said Popocatépetl erupted four times in the previous 24 hours, had 73 volcanic plumes and had two volcano tectonic earthquakes — measuring in magnitudes 1.2 and 1.6, respectively.

Popocatépetl is about 43 miles southeast of Mexico City.

CENAPRED in March raised the environmental alert level to the second degree out of three, meaning nearby residents should be prepared to evacuate.

“The CENAPRED urges you not to approach the volcano, especially the crater, due to the danger of falling ballistic fragments,” CENAPRED said in a statement.

Magma Build-Up May Put Salvadoran Capital At Risk

The build-up of magma six kilometres below El Salvador’s Ilopango caldera means the capital city of San Salvador may be at risk from future eruptions, University of Bristol researchers have found.

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A caldera is a large cauldron-like volcanic depression or crater, formed by the collapse of an emptied magma chamber. The depression often originates from very big explosive eruptions. In Guatemala and El Salvador, caldera volcanoes straddle tectonic fault zones along the Central American Volcanic Arc (CAVA). The CAVA is 1,500 kilometres long, stretching from Guatemala to Panama.

The team, from the Volcanology research group at Bristol’s School of Earth Sciences and the Ministry of the Environment and Natural Resources in El Salvador, studied the density distribution beneath the Ilopango caldera and the role tectonic stresses – caused by the movement of tectonic plates along fault lines – have on the build-up of magma at depth. Their study is published today in the journal Nature Communications.

The Ilopango caldera is an eight km by 11 kilometre volcanic collapse structure of the El Salvador Fault Zone. The collapsed caldera was the result of at least five large eruptions over the past 80,000 years.

The last of these occurred about 1,500 years ago and produced enough volcanic ash to form a 15 centimetre thick layer across the entire UK. This catastrophic eruption destroyed practically everything within a 100 kilometre radius, including a well-developed native Mayan population, and significantly disturbed the Mayan populations as far as 200 kilometres away.

The most recent eruptions occurred in 1879–1880 and were on a much smaller scale than the previous one.

Project leader and co-author Dr Joachim Gottsmann said: “Most earthquakes take place along the edges of tectonic plates, where many volcanoes are also located. There is therefore a link between the breaking of rocks, which causes faults and earthquakes and the movement of magma from depth to the surface, to feed a volcanic eruption. The link between large tectonic fault zones and volcanism is, however, not very well understood.”

Existing studies show that magma accumulation before a large caldera-forming eruption, as well as the caldera collapse itself, may be controlled by fault structures.

“However, it is unclear to what extent regional tectonic stresses influence magma accumulation between large caldera-forming eruptions.”, co-author Professor Katharine Cashman said.

Lead author Jennifer Saxby, whose research towards a MSc in Volcanology contributed to the study, said: “Addressing this question is important not only for understanding controls on the development of magmatic systems, but also for forecasting probable locations of future eruptive activity from caldera-forming volcanoes.”

The team discovered that the current tectonic stress field promotes the accumulation of magma and hydrothermal fluids at shallow (< 6km) depth beneath Ilopango. The magma contains a considerable amount of gas, which indicates the system is charged to possibly feed the next eruption.

Dr Gottsmann said: “Our results indicate that localised extension along the fault zone controls the accumulation, ascent and eruption of magma at Ilopango. This fault-controlled magma accumulation and movement limits potential vent locations for future eruptions at the caldera in its central, western and northern part – an area that now forms part of the metropolitan area of San Salvador, which is home to 2 million people. As a consequence, there is a significant level of risk to San Salvador from future eruptions of Ilopango.”

Warming Pulses In Ancient Climate Record Link Volcanoes, Asteroid Impact And Dinosaur-Killing Mass Extinction

A new reconstruction of Antarctic ocean temperatures around the time the dinosaurs disappeared 66 million years ago supports the idea that one of the planet’s biggest mass extinctions was due to the combined effects of volcanic eruptions and an asteroid impact.

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Two University of Michigan researchers and a Florida colleague found two abrupt warming spikes in ocean temperatures that coincide with two previously documented extinction pulses near the end of the Cretaceous Period. The first extinction pulse has been tied to massive volcanic eruptions in India, the second to the impact of an asteroid or comet on Mexico’s Yucatan Peninsula.

Both events were accompanied by warming episodes the U-M-led team found by analyzing the chemical composition of fossil shells using a recently developed technique called the carbonate clumped isotope paleothermometer.

The new technique, which avoids some of the pitfalls of previous methods, showed that Antarctic ocean temperatures jumped about 14 degrees Fahrenheit during the first of the two warming events, likely the result of massive amounts of heat-trapping carbon dioxide gas released from India’s Deccan Traps volcanic region. The second warming spike was smaller and occurred about 150,000 years later, around the time of the Chicxulub impact in the Yucatan.

“This new temperature record provides a direct link between the volcanism and impact events and the extinction pulses — that link being climate change,” said Sierra Petersen, a postdoctoral researcher in the U-M Department of Earth and Environmental Sciences.

“We find that the end-Cretaceous mass extinction was caused by a combination of the volcanism and meteorite impact, delivering a theoretical ‘one-two punch,'” said Petersen, first author of a paper scheduled for online publication July 5 in the journal Nature Communications.

The cause of the Cretaceous-Paleogene (KPg) mass extinction, which wiped out the non-avian dinosaurs and roughly three-quarters of the planet’s plant and animal species about 66 million years ago, has been debated for decades. Many scientists believe the extinction was caused by an asteroid impact; some think regional volcanism was to blame, and others suspect it was due to a combination of the two.

Recently, there’s been growing support for the so-called press-pulse mechanism. The “press” of gradual climatic change due to Deccan Traps volcanism was followed by the instantaneous, catastrophic “pulse” of the impact. Together, these events were responsible for the KPg extinction, according to the theory.

The new record of ancient Antarctic ocean temperatures provides strong support for the press-pulse extinction mechanism, Petersen said. Pre-impact climate warming due to volcanism “may have increased ecosystem stress, making the ecosystem more vulnerable to collapse when the meteorite hit,” concluded Petersen and co-authors Kyger Lohmann of U-M and Andrea Dutton of the University of Florida.

To create their new temperature record, which spans 3.5 million years at the end of the Cretaceous and the start of the Paleogene Period, the researchers analyzed the isotopic composition of 29 remarkably well-preserved shells of clam-like bivalves collected on Antarctica’s Seymour Island.

These mollusks lived 65.5-to-69 million years ago in a shallow coastal delta near the northern tip of the Antarctic Peninsula. At the time, the continent was likely covered by coniferous forest, unlike the giant ice sheet that is there today.

As the 2-to-5-inch-long bivalves grew, their shells incorporated atoms of the elements oxygen and carbon of slightly different masses, or isotopes, in ratios that reveal the temperature of the surrounding seawater.

The isotopic analysis showed that seawater temperatures in the Antarctic in the Late Cretaceous averaged about 46 degrees Fahrenheit, punctuated by two abrupt warming spikes.

“A previous study found that the end-Cretaceous extinction at this location occurred in two closely timed pulses,” Petersen said. “These two extinction pulses coincide with the two warming spikes we identified in our new temperature record, which each line up with one of the two ‘causal events.'”

Unlike previous methods, the clumped isotope paleothermometer technique does not rely on assumptions about the isotopic composition of seawater. Those assumptions thwarted previous attempts to link temperature change and ancient extinctions on Seymour Island.

Volcanoes Get Quiet Before They Erupt

When dormant volcanoes are about to erupt, they show some predictive characteristics–seismic activity beneath the volcano starts to increase, gas escapes through the vent, or the surrounding ground starts to deform. However, until now, there has not been a way to forecast eruptions of more restless volcanoes because of the constant seismic activity and gas and steam emissions.

volcano

Carnegie volcanologist Diana Roman, working with a team of scientists from Penn State, Oxford University, the University of Iceland, and INETER has shown that periods of seismic quiet occur immediately before eruptions and can thus be used to forecast an impending eruption for restless volcanoes. The duration of the silence can indicate the level of energy that will be released when eruption occurs. Longer quiet periods mean a bigger bang.

The research is published in Earth and Planetary Science Letters.

The team monitored a sequence of eruptions at the Telica Volcano in Nicaragua in 2011. It is a so-called stratovolcano, with a classic-looking cone built up by many layers of lava and ash. They started monitoring Telica in 2009 with various instruments and by 2011 they had a comprehensive network within 2.5 miles (4 kilometers) of the volcano’s summit.

The 2011 eruptive event was a month-long series of small to moderate ash explosions. Prior to the eruption, there was a lack of deep seismicity or deformation, and small changes in sulfur dioxide gas emissions, indicating that the eruption was not driven by fresh magma. Instead, the eruption likely resulted from the vents being sealed off so that gas could not escape. This resulted in an increase in the pressure that eventually caused the explosions.

Of the 50 explosions that occurred, 35 had preceding quiet periods lasting 30 minutes or longer. Thirteen explosions were preceded by quiet intervals of at least five minutes. Only two of the 50 did not have any quiet period preceding the explosion.

“It is the proverbial calm before the storm,” remarked Roman. “The icing on the cake is that we could also use these quiet periods to forecast the amount of energy released.”

The researchers did a “hindsight” analysis of the energy released. They found that the longer the quiet phase preceding an explosion, the more energy was released in the ensuing explosion. The quiet periods ranged from 6 minutes before an explosion to over 10 hours (619 minutes) for the largest explosion.

The researchers were also able to forecast a minimum energy for impending explosions based on the data from the previous quiet/explosion pairs and the duration of the particular quiet period being analyzed. The correlation between duration of quiet periods and amount of energy released is tied to the duration of the gas pathways being blocked. The longer the blockage, the more pressure builds up resulting in more energy released. Sealing might be occurring due to mineral precipitation in cracks that previously acted as gas pathways, or due to the settling of the rock near the volcano’s surface.

“What is clear is that this method of careful monitoring of Telica or other similar volcanoes in real time could be used for short-term forecasts of eruptions,” Roman said. “Similar observations of this phenomenon have been noted anecdotally elsewhere. Our work has now quantified that quiet periods can be used for eruption forecasts and that longer quiet periods at recently active volcanoes could indicate a higher risk of energetic eruptions.”

The paper’s other authors are Mel Rodgers of Oxford University, Peter LaFemina of Penn State University, Halldor Geirsson of the University of Iceland, and Virginia Tenorio of the Instituto Nicaraguense de Estudios Territoriales.

This work was supported by the National Science Foundation and the Nicaraguan Institute of Earth Sciences (INETER).