Don’t be fooled by the name—Iceland is one of the hottest hotspots in the world, geologically speaking. The island’s volcanic legacy reared its head again yesterday as a massive eruption by a volcano beneath a glacier caused the evacuation of hundreds of residents and created ash clouds that delayed flights all around Northern Europe.
The volcano, called Eyjafjallajokull, rumbled last month, but that was nothing like this. “This is a very much more violent eruption, because it’s interacting with ice and water,” said Andy Russell, an expert in glacial flooding at the University of Newcastle in northern England. “It becomes much more explosive, instead of a nice lava flow oozing out of the ground” [AP]. The flood caused by melted glacial ice caused the evacuation about 800 people. Waters threatened to spill over onto Highway 1, Iceland’s main highway that makes a circuit around the island. But some quick digging by construction crews altered the course of the water.
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The bottom of the sea is a strange and marvelous frontier, as we were reminded last week by the discovery of the first known animals to live without oxygen. Today a team of British researchers say their undersea robotic explorers have found something new down in the depths of the Caribbean Sea: the deepest hydrothermal vents ever seen.
The black smokers, named for how they spew out an iron sulfide compound that’s black, sit 3.1 miles deep in the Cayman Trough in the Caribbean [FoxNews]. They beat out the previous record holders, which were located 2.6 miles below the surface in the middle of the Atlantic Ocean. As the National Oceanography Centre team sailed across the sea in its research vessel, the James Cook, the scientists deployed their robot explorers down to the inhospitable depths. One, called Autosub6000, mapped the seafloor while another, HyBIS, carried high-resolution cameras to capture these images.
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The moment you read this, volcanic eruptions could be happening on Venus.
Planetary astronomers have been debating whether Venus is or was geologically active, and whether the geologic hotspots previous missions saw mean that Venus is one of the few places in the solar system to have experienced volcanism. Now, according to data from the European Space Agency’s Venus Express mission, there’s every reason to believe that Venus not only has been geologically active and volcanic during its lifetime, but also might still be today, according to Jörn Helbert, coauthor of the study in Science. “The solidified lava flows, which radiate heat from the surface, seem hardly weathered. So we can conclude that they are younger than 2.5 million years old — and the majority are probably younger than 250,000 years…. In geological terms, this means that they are practically from the present day” [Wired.com].
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Earlier this month, a study in the journal Science tried to put to bed for good the question of dinosaur extinction: It was an impact from space, not large-scale volcanic activity, that wiped them out 65 million years ago, the study argued. That’s all well and good for the dinosaur’s end, but what about their beginning?
This week in the Proceedings of the National Academy of Sciences, paleontologists say they’ve studied the period about 200 million years ago when dinosaurs first came to power, and found that while catastrophic volcanic activity may not explain dinosaur extinction, it could have explained why dinosaurs’ competitors disappeared and the terrible lizards took over the planet.
Around the time of dino emergence, the continents were all locked up in the supercontinent Pangaea. As it pulled apart, researchers say the seismic activity gave rise to hundreds of thousands of years of volcanic activity, creating lava fields on the surface of the Earth the size of the continental United States. For this study, Jessica Whiteside and colleagues surveyed wood remnants, wax from ancient leaves, and whatever else they could extract from the volcanic flow’s remains to reconstruct what was happening in the climate of this period.
The scientists examined how two different isotopes (or forms) of carbon fluctuated during these volcanic eruptions. They found that the “heavy” form of carbon was depleted relative to the “light” form. They say this reflects disturbances in the carbon cycle at this time, including a spike in atmospheric carbon dioxide (CO2) and aerosols (fine solid particles) [BBC News].
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Will we ever get a solid answer on what killed the dinosaurs? According to a new “K-T Boundary Dream Team” comprising of 41 international experts, including geophysicists and paleontologists, yes, the question has been settled: An asteroid is indeed to blame.
For years, scientists have argued over different theories of what killed the dinos–including one hypothesis that has gained ground recently, which suggests that massive volcanic activity in India’s Deccan Traps wiped them out 65 million years ago. However, the latest expert panel stuck to the asteroid theory, saying a massive impact wiped out the dinos and more than half of the Earth’s other species. The panel’s review was published in the journal Science.
After studying all the available data on the Cretaceous-Tertiary (K-T) mass extinction, the panel concluded that the catastrophic event was caused by a 6-mile-wide asteroid that struck Earth at an angle of 90 degrees and a speed of about 12.4 miles per second – about 20 times faster than a speeding bullet [Guardian]. The asteroid hit Chicxulub, Mexico, with a force one billion times more powerful than the atomic bomb at Hiroshima [Science Daily News].
The impact of the crash would have triggered large scale fires, landslides, earthquakes that measured 10 on the Richter scale, and subsequent tsunamis, scientists said. Debris loosened by the impact would have shrouded the planet, clouding the skies, causing a global darkness, and “killing off many species that couldn’t adapt to this hellish environment” [Science Daily News], according to study coauthor Joanna Morgan.
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African chimpanzees know how to handle wildfire, as DISCOVER noted last month. But lava is a different deal. Nyamulagira, a volcano in the Democratic Republic of the Congo, began to erupt over the weekend and threatened not only the people nearby, but also the endangered primates that live in the area. The southerly lava flow appears to have spared most human settlements and the mountain gorillas of Virunga National Park, but the native chimps haven’t been so lucky.
The 40 eastern chimpanzees that live on Nyamulagira itself could still be at risk if they are surrounded by lava, and as the plants they rely on for food become coated by abrasive volcanic ash. Park officials hope animals in the lava’s path will simply move away from it [New Scientist]. United Nations peacekeepers, who are in the Congo to protect civilians from the seemingly unending war there, have offered the country’s leaders the use of UN planes and helicopters to monitor the situation.
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Krypton and xenon make up trace amounts of the Earth’s atmosphere—about one part per million for the former, and even less for the latter. But these minor components could have a major impact in scientists’ understanding of how the atmosphere came to be. According to findings published in Science, many of the atmosphere’s gases that you’re breathing right now might have come from outer space rather than inside the Earth, as previously thought.
Researchers believed that when the Earth congealed from the gas and dust cloud that formed the solar system, some gases got trapped in the planet’s mantle. Then, over hundreds of millions of years, volcanic eruptions returned the gases to Earth’s surface, where gravity kept them from drifting off into space. The mixing of these gases–along with the oxygen and other molecules added by life–created the atmosphere we have today [ScienceNOW Daily News]. That’s been the common wisdom, anyway.
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A super-colossal volcanic eruption rocked Italy 39,000 years ago, and troubling signs at the site, now known as Campi Flegrei, have many scientists wondering when the next big one will hit. To probe the issue, so to speak, the Campi Flegrei Deep Drilling Project will drill nearly 2.5 miles down into the collapsed volcanic crater to find out if another blast is on the horizon. Though the researchers on this particular project point out that any risk is small, it will begin amid debate about whether such endeavours are safe, given the unknowns of a volcano’s interior. A few say drilling might even trigger a major eruption [New Scientist]. However, scientists on the project say this isn’t likely, as their drills won’t dig deep enough to set off an eruption.
Campi Flegrei isn’t well known because it lacks a volcanic cone, but it dwarfs Mount Vesuvius. All of Naples sits within its caldera, an eight-mile-wide collapsed area of land formed by the eruption 39,000 years ago. A similar volcanic eruption would leave large parts of Europe buried under ash, say scientists, however smaller eruptions occur every few centuries; the last eruption was in 1538. The researchers hope that by drilling into the volcano, they’ll learn if another smaller eruption is imminent. They hope to locate fracture zones and magma pools that could only be guessed at without drilling. This could show exactly where magma might ascend and collect prior to an eruption. Meanwhile, rock samples could be tested under high stresses in the lab to help model the ground deformation prior to eruption [New Scientist]. The caldera’s center has risen about 10 feet since the 1960s, which has lit a fire under the researchers since a similar rise proceeded a series of intense eruptions 4,000 years ago.
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In 2005, the earth cracked open in Ethiopia. Two volcanic eruptions shook the desert, and a 35-mile-long rift opened in the land, measuring 20 feet wide in some places. Now a new study adds weight to the argument that the opening of this crack marks the first step in the formation of a new sea that may eventually separate East Africa from the rest of the continent. Says lead researcher Atalay Ayele: “The ocean’s formation is happening slowly, likely to take a few million years. It will stretch from the Afar depression (straddling Ethiopia, Eritrea and Djibouti) down to Mozambique” [ABC News].
The study, to be published in the journal Geophysical Research Letters, explains that the seismic movements observed in Ethiopia are very similar to the changes wrought by faults and fissures on the seafloor, where the processes that move tectonic plates usually begin.
Seismic data from 2005 shows that the rift opened in a matter of days. Dabbahu, a volcano at the northern end of the rift, erupted first, then magma pushed up through the middle of the rift area and began “unzipping” the rift in both directions, the researchers explained in a statement today. “We know that seafloor ridges are created by a similar intrusion of magma into a rift, but we never knew that a huge length of the ridge could break open at once like this” [LiveScience], says study coauthor Cindy Ebinger.
The active volcanic region in Ethiopia’s Afar desert sits at the boundary of the African and Arabian tectonic plates, which have been gradually spreading apart for millions years; the new study shows that large-scale seismic events can speed up that process. The gradual separation has already formed the 186-mile Afar depression and the Red Sea. The thinking is that the Red Sea will eventually pour into the new sea in a million years or so [LiveScience].
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DISCOVER: Meet the New Continent: East Africa
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80beats: Tremors Point to a Stressed-Out Stretch of the San Andreas Fault
80beats: Armed With Data, Scientists Still Mystified by Antarctica’s Hidden Mountains
80beats: Ancient Continental Collisions May Have Provided Air to Breathe
Image: University of Rochester
Some of the world’s baddest volcanoes, like Chile’s Chaitén volcano that erupted in 2008, are actually even worse than scientists previously thought. A study of Chaitén’s eruption revealed that locals only had 30 hours to to flee from first time they felt rumbling, not the weeks or months that it typically takes a volcano to go from tremors to eruption. That’s because Chaitén is a rhyolitic volcano; these volcanoes are largely fueled by a silica-based, very flow-resistant magma and they tend to build pressure over time before erupting violently [National Geographic News]. Thousands were able to escape before Chaitén’s blast, but scientists are warning that others living in the shadow of a rhyolitic volcano may not be so lucky.
The magma of the Chaitén volcano traveled up to 3 feet per second, according to the study published in Nature. It shot from a depth of more than five kilometres [3 miles] to the surface in about four hours…. The violent and unexpected nature of the blasts, together with their rarity, means the Chaiténeruption is the first rhyolite event to have been scientifically assessed in this way [ABC News]. In the U.S. there are large rhyolitic volcanoes in Wyoming, California, and New Mexico as well as in the Japanese islands and New Zealand’s Taupo Volcanic Zone. Scientists are saying that even though rhyolitic eruptions are rare, the study should serve as a warning call to step up monitoring of potentially active volcanoes.
Related Content:
80beats: In the Permian Period, Erupting Super-Volcanoes May Have Killed Half the Planet
80beats: Forget “The Asteroid”: Could Supervolcanoes Have Killed the Dinosaurs?
80beats: Undersea Volcanoes Decimated Marine Life in the Primordial Oceans
Image: Jonathan Castro
The dormant Hawaiian volcano Mauna Kea has been selected as the site of the world’s largest telescope, the much-anticipated Thirty Meter Telescope. Its enormous mirror will have nine times the light-gathering capacity as the biggest telescopes operating today, and will be able to look back to the beginnings of the universe. “It will really provide the baby pictures of the universe” [Honolulu Advertiser], says Charles Blue, a spokesman for the Thirty Meter Telescope Observatory Corporation.
The telescope’s mirror, stretching 30 meters (almost 100 feet) in diameter, will be so large that it should be able to gather light that will have spent 13 billion years traveling to earth. This means astronomers looking into the telescope will be able to see images of the first stars and galaxies forming — some 400 million years after the Big Bang [AP]. The telescope is expected to be completed by 2018, but it may not be the world’s largest for long–the European Extremely Large Telescope is scheduled for completion around the same time, and will boast a 138-foot mirror.
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When the Messenger spacecraft swooped low past the planet Mercury on October 6 2008, it gathered up a wealth of data that will have planetary scientists puzzling for years. As researchers sort through findings regarding Mercury’s volcanic past, meteor impacts, and the effect of the solar wind on the innermost planet’s magnetosphere, one broad conclusion stands out: Mercury isn’t just a boring chunk of rock. Marilyn Lindstrom, a NASA program scientist, said the Messenger findings show that Mercury is “just an amazingly dynamic planet, both in the past and in the present” [Baltimore Sun].
Superficially, Mercury looks a lot like the moon: small, grayish-brown and pockmarked with craters. Some scientists assumed that Mercury’s surface formed the same way the moon’s did, with lighter rocks rising to the surface of a magma ocean and congealing into a brittle crust early on. But the new observations reveal that 40 percent of the surface was formed by volcanoes. “Up until before Messenger’s arrival, we weren’t even sure that volcanism existed on Mercury” [Wired], says researcher Brett Denevi. The presence of titanium oxide also suggests that the planet was hot enough in its first 100 million years to be covered in magma oceans.
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About 2.7 billion years ago, the primordial seas already hosted the first photosynthetic microbes, the blue-green algae that took in carbon dioxide and released oxygen into the air. But they were outnumbered by methane-producing bacteria called methanogens [that] thrived in nickel-rich seas. The high amounts of methane that this early life pumped into the environment prevented oxygen accumulation in the atmosphere because the methane reacted with any oxygen, creating carbon dioxide and water [Science News], according to one theory. Now, a group of researchers say they’ve found the trigger that allowed oxygen to build up, and therefore allowed for a profusion of oxygen-breathing life.
The secret was the concentrations of the metal nickel, according to the new study, published in Nature. The scientists found that by analysing a type of sedimentary rock known as banded-iron formations they could monitor levels of nickel in the oceans of the early Earth dating as far back as 3.8 billion years ago. They found there was a marked fall in nickel between 2.7 billion and 2.5 billion years ago [The Independent]. That stretch of time correlates with what researchers call the Great Oxidation Event, when oxygen began to take hold in the atmosphere.
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Saturn‘s moon Titan is already an object of fascination to astronomers: The moon has seasonal weather patterns, a thick atmosphere, and lakes of liquid methane on its surface, and some scientists think it’s one of the likeliest spots to find extraterrestrial life in our solar system. Now, researchers have found new evidence that the moon has cryovolcanoes, which, in the cold of the outer Solar System, would spew a slurry of ice and liquid hydrocarbons, instead of lava. “It’s as if it’s a sort of constant bubbling cauldron that occasionally explodes big time,” says Robert Nelson, a Cassini team scientist [Nature News].
The still-controversial theory regards an area of Titan called Hotei Arcus, which appears to fluctuate in brightness on timescales of several months…. The cryovolcanism idea was bolstered in 2008, when observations of Hotei Arcus by a radar instrument aboard NASA’s Cassini probe revealed structures that resembled lava flows [New Scientist]. The new findings, discussed at this week’s Lunar and Planetary Science Conference, are based on radar images taken by Cassini on recent flybys of the moon (radar is required to penetrate Titan’s thick methane atmosphere). Overlapping images were used to create a topographical map of Hotei Arcus; the map shows several lobe-like formations, more than 300 feet high, which researchers say resemble the oozing of a viscous, lava-like material.
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The Alaskan volcano Mount Redoubt erupted last night with four large explosions, sending an plume of ash 50,000 feet into the air, the Alaska Volcano Observatory reported. The volcano lies only 100 miles southwest of Anchorage, Alaska’s largest city, but geologists say that current wind patterns are likely to carry the ash cloud to the north. “It looks like (Anchorage) might dodge the bullet,” Alaska Volcano Observatory geophysicist Peter Cervelli said [Anchorage Daily News]. Mudflows are also possible on nearby rivers.
The 10,200-foot Mount Redoubt last erupted during a four-month period from 1989-90…. Alaska volcanos typically explode and shoot ash upward, sometimes to 50,000 feet, high into the jet stream. An eruption of Redoubt on Dec. 15, 1989, sent ash 150 miles away into the path of a KLM jet, stopping its engines. The jet dropped more than two miles before the crew was able to restart engines and land safely at Anchorage [Fox News]. This time, Anchorage airport officials say they’ve canceled some flights, but have no immediate plans to close the airport.
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