What on Earth Is This Fiery Blob?


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What on Earth Is This Fiery Blob?

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What on Earth Is This Fiery Blob?

This impressive blob is a 65-foot (20 meters) high lava dome fountain that was photographed in Hawaii on Oct. 11, 1969.

Credit: USGS

At first glance, it looks like a fiery monster out of “The Incredibles.” Or maybe a glowing alien orb, or a giant, irritated zit popping up above the Earth’s surface.

But it’s neither. Rather, it’s an incredibly rare, 65-foot-tall (20 meters) lava-dome fountain.

Normally, volcanoes erupt lava in powerful jets that look like fountains gone wild. But in this photo — captured Oct. 11, 1969, in Hawaii — the lava spurted out symmetrically, forming an aesthetically pleasing lava-dome fountain. [History’s Most Destructive Volcanoes]

The U.S. Geological Survey (USGS) tweeted the photo on March 29 for Throwback Thursday (#TBT), a popular hashtag used when people post nostalgic photos from their past on social media.

The red-hot lava fountain certainly is a nostalgic moment for the USGS. This particular fountain was part of the Mauna Ulu eruption, which lasted (on and off) for an astonishing five years, from May 1969 until July 1974,according to the USGS.

Mauna Ulu is a volcanic cone on the east rift zone of the Kilauea volcanoon the Big Island of Hawaii. At the time Mauna Ulu erupted, it was the longest-lasting and most voluminous eruption on Kilauea’s eastern side in at least 2,200 years, the USGS said. The 1,774-day eruption spewed out about 460 million cubic yards (350 million cubic meters) of lava — enough to fill 140,000 Olympic-size swimming pools.

Mauna Ulu no longer holds the record for the longest-erupting volcano. Pu’u ‘Ō’ō, a volcanic vent on Kilauea’s east rift zone, has erupted nearly continuously since January 1983, according to a 2003 report from the USGS. But despite Pu’u ‘Ō’ō’s feat, “the Mauna Ulu eruption was more accessible to the public, with a viewing platform established at one point to observe a lava lake in the crater,” the USGS said.

The fountain pictured here spewed out lava from Oct. 10 to Oct. 13, 1969, relatively early in Mauna Ulu’s epic eruption. (As a side note, the perspective of the photo makes it look as if the lava were coming out of the water. But it’s actually on land, and those “waves” are ripples of lava.)

Typically, lava fountains occur when gas bubbles rapidly form and expand in molten rock, which prompts jets of lava to spray outward, the USGS said. Though impressive, Mauna Ulu’s fountain wasn’t on the big side; lava fountains range from about 30 to 330 feet (10 to 100 m) in height, and some have reached the incredible height of 1,640 feet (500 m), the USGS reported.

Geologists have found that lava fountains can gush out of isolated vents and fissures, from active lava lakes and from lava tubes that are exposed to water.

Original article on Live Science.

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8 Trillion ‘Gallons’! Huge Blob of Magma Found Atop Undersea Volcano


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8 Trillion ‘Gallons’! Huge Blob of Magma Found Atop Undersea Volcano

 8 Trillion 'Gallons'! Huge Blob of Magma Found Atop Undersea Volcano

Credit: Shutterstock

A giant undersea caldera near Japan hosts a lava dome made from 8 trillion gallons of molten rock.

The dome, which is 6.2 miles (10 kilometers) wide and 1,968 feet (600 meters) tall, is solid rock now, and it doesn’t presage an impending eruption. However, it does add a new wrinkle to the history of the Kikai caldera, a huge depression that formed during a massive volcanic super-eruption about 6,300 or 7,300 years ago (the broad range has to do with different methods of dating the eruption). That eruption sent heated pyroclastic flow 50 miles (80 km) across the sea and spread ash up to 620 miles (1,000 km) away, said Yoshi Tatsumi, the author of a new study on the caldera’s inner workings, published today (Feb. 9) in the journalScientific Reports.

The system is still active, and it’s a relatively high-risk place for eruptive activity, said Erik Klemetti, a volcanologist at Denison University, who was not involved in the study. The volcano also blew its top in super-eruptions95,000 years ago and about 140,000 years ago. It occasionally burps ash and steam even in the modern day, with the last recorded eruption occurring between 2013 and 2014. [The 11 Biggest Volcanic Eruptions in History]

But because the caldera is hidden underwater, it’s hard to keep tabs on its activity. Tatsumi and his colleagues conducted multiple remotely-operated-vehicle dives to the caldera floor, south of Kyushu Island in the Japanese archipelago. They used sonar to map the caldera’s floor and shot small explosive charges into the seafloor to create seismic waves they could record and use to image the subsurface. The team also collected data on the water column’s chemistry and took rock samples from the looming dome in the center of the caldera.

This relief map shows the Kikai caldera: The inner and outer caldera are shown in solid lines. The blue diamonds indicate the diving sites of the remotely operated vehicle (ROV).

This relief map shows the Kikai caldera: The inner and outer caldera are shown in solid lines. The blue diamonds indicate the diving sites of the remotely operated vehicle (ROV).

Credit: Tatsumi et al., Scientific Reports, doi:10.1038/s41598-018-21066-w

The findings proved that the dome was, in fact, built up from lava, specifically a form of lava called rhyolite — some 8 trillion gallons (32 cubic kilometers) of it. This dome could have formed anytime since the last eruption, Klemetti said, so it isn’t clear how new it is. However, Tatsumi and his colleagues found that its chemical composition is different than the lava ejected from the caldera during the last super-eruption. This finding suggests that a new magma system formed after the eruption, Tatsumi told Live Science.

“The post-caldera activity, at least [at] this caldera, is regarded as the preparation stage to the next super-eruption, not as the calming-down stage from the previous super- eruption,” he said.

That doesn’t mean an eruption is imminent, but that the volcanic system that underpins the caldera has been changing and evolving over the millennia, the researchers reported. It’s interesting to see that the lava dome apparently originates from a different part of the magmatic system (underground chambers of molten rock) than the last super-eruption’s lavas, Klemetti said. [50 Amazing Facts About Volcanoes]

The best way to be sure the dome has a separate origin would be to test the minerals in the lavas and to find out when they formed, whether before the caldera-forming super-eruption, around the same time or after, Klemetti said. Tatsumi and his team plan to look deeper under the caldera. Given the giant size of the lava dome, there could be a large magma reservoir under the surface, Tatsumi said. The team plans to use subsurface imaging to look for that reservoir and describe it if it exists.

Original article on Live Science

Lava Gulps Down GoPro Camera, Which Records the Entire, Fiery Affair


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Lava Gulps Down GoPro Camera, Which Records the Entire, Fiery Affair

 https://www.livescience.com/61085-lava-engulfs-gopro-camera.html

The internet is awash with extreme videos, but footage of lava barreling toward and then melting the lens of a GoPro camera may be one of the hottest (literally) recordings online.

The fiery affair happened on Aug. 10, 2016, when Kilauea EcoGuides tours owner and lead guide Erik Storm took a group of tourists from San Francisco to Hawai’i Volcanoes National Park, according to National Geographic. The video resurfaced this month after Erez Marom, an Israeli photographer, accidently melted a drone camera when he flew it too close to lava flows in Hawaii, renewing interest in flaming-hot lava footage.

Storm captured the recording when he showed the tour group a fast-moving lava flow in the park that day. Storm put his GoPro Hero4 Black camera into a crevice to capture a recording of the molten rock, but he made what he now calls “a $400 mistake” — he didn’t pull out the camera in time, National Geographic reported. [50 Amazing Volcano Facts]

At least Storm has a good excuse for losing his GoPro to a molten blob. He was busy telling the tourists a story about Pele, the Polynesian fire goddess, he told National Geographic. After the scorching incident, he set to work retrieving the camera.

Don't drop your GoPro in the searing lava.
Don’t drop your GoPro in the searing lava.

Credit: Shutterstock

“I had a geologist rock hammer with me, and that is how I was able to get it out of the now cooling rock,” Storm wrote on Storyful, a video site. “When I got home, I hammered all the hardened rock off of the camera and was amazed to see the blue Wi-Fi light still blinking!”

Amazingly, the camera could still turn on, although the lens had melted, rendering it unusable. “The SD [secure digital] card popped right out and the footage was intact,” he told Storyful. “At the end of the video, you can see me with the rock hammer.”

It’s no wonder the lava melted Storm’s camera. Crawling, dark-red lava on Hawaii can reach temperatures of 895 degrees Fahrenheit (479 degrees Celsius), according to the U.S. Geological Survey (USGS), Live Science previously reported.

Bright-red lava flows are even hotter, reaching upward of 1,165 degrees F (629 degrees C), and glowing, orange lava indicates the molten rock is a steaming 1,600 degrees F (871 degrees C) or so, Live Science reported.

Despite the great footage, Storm doesn’t recommend that other people mess with lava: Many native Hawaiians consider lava to be sacred.

“No one should ever poke the lava with anything, cook with the lava orthrow anything into or in front of the flowing lava to ‘see what happens,'” Storm told Storyful. “I respect the place where I work to the fullest and work hard to make sure people understand that this is a very sacred place that commands respect.”

Original article on Live Science.

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Massive Calved Iceberg Comes into View as Antarctic Sun Rises


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Massive Calved Iceberg Comes into View as Antarctic Sun Rises

Massive Calved Iceberg Comes into View as Antarctic Sun Rises
Instruments aboard the Landsat 8 satellite captured these visible and thermal images on Sept. 16, 2017, of the A68 iceberg that snapped off Antarctica’s Larsen C Ice Shelf.

Credit: NASA Earth Observatory

As the sun rises above the Antarctic horizon after the long, dark austral winter, scientists are getting a better look at the Delaware-size iceberg that sheared off from the frozen continent’s Larsen C ice shelf in July.

With the illumination from the sun’s rays, new satellite images have captured the iceberg, dubbed A68, and the motley assortment of ice and water surrounding it, in impressive detail. In the coming months and years, scientists will be poring over such images to watch the progression of the iceberg and its parent ice shelf.

The researchers said they also hope to study the area up close, to examinedetails of the seafloor that have been blocked by ice for hundreds of yearsand to learn how such a massive shift could alter the local ecosystem. [In Photos: Antarctica’s Larsen C Ice Shelf Through Time]

“It’s obviously a completely different physical environment once the ice is gone,” Susie Grant, a marine biogeographer with the British Antarctic Survey, told Live Science.

Keeping tabs on the iceberg, the ice shelf and the ecosystem in the coming years could also help scientists better understand how other major ice shelves might respond to a warming world, according to Grant.

Scientists have watched for several years as a rift slowly propagated its way across the Larsen C ice shelf, a platform of ice that extends out from the coast and floats atop the ocean. After a couple of surges in 2016 and earlier this year, the rift finally reached the edge of the ice shelf and calved off the iceberg.

Snapshot of the rift in the Larsen C on Nov. 10, 2016.

Credit: John Sontag/NASA

But with the sun below the Antarctic horizon, researchers could monitor the event only with thermal imagery and radar, according to NASA’s Earth Observatory.

“When it did finally break off, it was just sort of these tantalizing” glimpses, Grant said.

Once the sun re-emerged in August, more satellite views started streaming in ¾ and they haven’t disappointed. The “satellite images are extraordinary,” Grant said. “To see something of that scale moving across the water.”

In mid-September, NASA’s Terra satellite and the Landsat 8 satellite captured shots of the iceberg in visible light and of the surrounding area in infrared wavelengths of light. The images reveal exciting details, like the wrinkly-looking rifts that stretch across parts of the iceberg and the mixture of open water and ice surrounding it. [Earth from Above: 101 Stunning Images from Orbit]

An instrument onboard the Terra satellite captured this image of the A68 iceberg on Sept. 11, 2017.

An instrument onboard the Terra satellite captured this image of the A68 iceberg on Sept. 11, 2017.

Credit: NASA Earth Observatory

In the psychedelic thermal image, the cold iceberg and ice shelf appear a ghostly white, while the relatively warmer sea ice shows up in shades of purple, and the even warmer (though still sub-freezing) open water pops out in yellow. Bluer shades show the mixture of ice called mélange, which can include snow, sea ice, bits of ice that fell from the sides of the rift and something called marine ice, which forms along the underside of the floating ice, said Ala Khazendar, a scientist with NASA’s Jet Propulsion Laboratory who uses radar to study polar ice.

The images also show how much the iceberg has moved away from its parent ice shelf. So far, it has been progressing at a steady clip, but how fast it might continue to move is unclear and depends on several factors: winds and ocean currents, as well as whether there are any bumps or ridges on the seafloor that the iceberg might get stuck on, Khazendar said.

If it does get stuck, he said, that will tell scientists something about the topography of the seafloor, which they had no way of viewing before the calving event, Grant said.

That seafloor and the water above it are also being exposed to sunlight for the first time in at least hundreds of years, and this could have major impacts on the local ecosystem, Grant said. For instance, ocean life at the water’s surface could suddenly ramp up in productivity. The newly opened area could also see species moving in from neighboring regions, she said. [Antarctica Photos: Meltwater Lake Hidden Beneath the Ice]

The ecosystem will be “potentially dramatically changed” by the calving event, Grant said, though it’s “impossible to know anything about that until we can get down and visit.”

The British Antarctic Survey and other groups are planning scientific cruises to get an up-close look at the changes to the region, and the sooner that happens the better, so they can establish a baseline before major changes occur, Grant said. Sediment cores drilled from the ocean floor will help scientists establish how long the area has been covered by ice, and sampling of the water will tell them how the temperature and salt content may be changing and what creatures live there, she said.

Those efforts are helped by an international agreement by the Commission for the Conservation of Antarctic Marine Living Resources, which has 25 international members, to designate the area around the ice shelf as a protected area so that activities like commercial fishing won’t hamper scientific work, Gizmodo reported. This is the first time there has been such a designation, Grant said.

“I think that was a really important step,” she said. “We were really pleased to have managed to get that.”

In the meantime, scientists will glean what information they can from satellite images and airborne observations made by NASA’s IceBridge program, which is gearing up for the Antarctic summer season, Khazendar said.

Researchers will be watching to see if the remaining ice shelf begins to flow faster in response to the iceberg’s loss, he said, and how the iceberg melts and potentially breaks up into smaller pieces (one such piece already broke off later in July).

“We still need to collect data and analyze them in order to understand how the Larsen C ice shelf is going to react to this event,” Khazendar said.

There are concerns that the massive calving event could mark a turning point for the glacier, sending it toward a global warming-fueled collapse like those suffered by its northern neighbors, Larsen A and Larsen B, in 1995 and 2002, respectively. But whether that will happen isn’t yet clear, and the ice shelf could recover from the calving event, as these events do happen naturally, Khazendar said.

“It will take us some time before we have some clearer answers,” he said.

How Larsen C responds could also give scientists a better idea of how other major ice shelves around Antarctica will respond to the warming waters that are lapping away at the shelves’ undersides and causing the glaciers that feed into shelves to flow faster out to the ocean, raising sea levels.

“It could teach us a lot about the fate of other large ice shelves in Antarctica,” Khazendar said

Studying the region could also “improve our understanding of how ecosystems might respond to the impacts of climate change,” Grant said.

Original article on Live Science.

These Stunning 3D Images Reveal How a Massive Greenland Glacier Has Changed


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These Stunning 3D Images Reveal How a Massive Greenland Glacier Has Changed

Watching a glacier

Credit: Jefferson Beck/NASA Goddard

What’s Causing So Many Earthquakes in Oklahoma?


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What’s Causing So Many Earthquakes in Oklahoma?

On Aug. 2, 2017, a 4.2-magnitude earthquake struck north central Oklahoma, a region that has seen an uptick in temblors since 2014.

Credit: USGS

A magnitude-4.2 earthquake hit just outside Edmond, Oklahoma, last night (Aug. 2) at 9:56 p.m. local time — the fifth significant temblor to shake this region of the state already this month, according to the U.S. Geological Survey.

The temblor originated at a depth of 1.9 miles (3 km), about 15 miles (24 km) northeast of Oklahoma City, the USGS said. According to the Edmond police department’s Twitter account, as of last night, no significant damage had been reported. News 9 in Oklahoma City reported that although 4,600 people were left without power after the quake, all power has since been restored. [The 10 Biggest Earthquakes in History]

But last night’s quake is part of a recent trend. Since Tuesday (Aug. 1), five earthquakes above magnitude 3.0 have been reported in this region, Xiaowei Chen, assistant professor of geophysics at the University of Oklahoma, told Live Science. It appears to be part of a longer sequence of earthquakes that began in 2014, she added. In fact, in 2014, the USGS issued an earthquake warning in the central part of the state — the first time the agency had ever issued such a warning for a state east of the Rockies.

Chen didn’t yet know enough about the most recent earthquake sequence to be able to comment on whether this recent magnitude-4.2 earthquake may signal that an even bigger earthquake will come, or if it’s simply within the range of expected seismic activity in the area, she said.

Although it’s difficult to attribute earthquakes to a particular cause, it’s possible that human activity induced this earthquake, William Yeck, a research geophysicist with the USGS Geologic Hazards Science Center, told Live Science. Since 2014, there has been a significant increase in the rate of earthquakes in north central Oklahoma, the area in which this recent earthquake occurred, he said.  The cause of this increase? Theinjection of wastewater — a byproduct of oil and gas production — into the ground may be to blame.

“The injection of fluids underground can increase underground pressures,” he said. “This, in turn, can effectively unclamp faults, allowing them to slip, which results in earthquakes.”

Last year, scientists reported that north central Oklahoma and the southernmost part of Kansas were at the greatest risk of a human-induced earthquake in the United States.

The high rate of earthquakes that began in 2014 began to drop off last year, which Yeck thinks may be due to the decrease in wastewater injection in this area.

“I just stress that [for] people [living] in an area that’s prone to earthquakes, preparedness is key,” he added.

Original article on Live Science.

 

Trillion-Ton Iceberg Breaks Off Antarctica


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Trillion-Ton Iceberg Breaks Off Antarctica

The European Space Agency’s Copernicus Sentinel-1 mission detected the huge chunk of ice that broke off Antarctica’s Larsen C ice shelf on July 12, 2017.

Credit: ESA

One of the largest icebergs ever recorded, packing about a trillion tons of ice or enough to fill up two Lake Eries, has just split off from Antarctica, in a much anticipated, though not celebrated, calving event.

A section of the Larsen C ice shelf with an area of 2,240 square miles (5,800 square kilometers) finally broke away some time between July 10 and today (July 12), scientists with the U.K.-based MIDAS Project, an Antarctic research group, reported today.

Scientists discovered the birth of this iceberg in data collected by an instrument aboard NASA’s Aqua satellite, called MODIS, which takes thermal infrared images. [In Photos: Antarctica’s Larsen C Ice Shelf Through Time]

The iceberg was expected, though scientists didn’t know when the crack in the ice sheet would finally release the floating chunk. The rift in the Larsen C ice shelf — the fourth-largest shelf in Antarctica — has been around for decades, but it wasn’t until November 2016 that satellite measurements revealed it had grown to more than 300 feet (91 m) in width and 70 miles (112 km) in length. The most recent measurements from this summer put the rift at 124 miles (200 km) long, with the now-calved iceberg hanging on by a thread; just 3 miles (5 km) of ice connected it with the rest of the ice shelf.

The Larsen C rift began to lengthen in January 2016. Images from July 12, 2017, show that part of the ice shelf had finally broken away.

The Larsen C rift began to lengthen in January 2016. Images from July 12, 2017, show that part of the ice shelf had finally broken away.

Credit: Swansea University/ESA

Even though the towering berg weighs more than 1.1 trillion tons (1 trillion metric tons), it won’t have a direct impact on sea-level rise. That’s because the ice was already floating on the sea. Even so, when an iceberg like this one calves, it can speed up the collapse of the rest of the ice shelf — the new iceberg reduced the area of the Larsen C ice shelf by 12 percent. Also, the ice shelf serves as a barrier to the land-based glacier that feeds the ice shelf; as that barrier diminishes, there’s more of a chance for the ice behind it to collapse into the sea, MIDAS researchers said.

And it’s this once-land-based ice that would impact sea levels, researchers say.

“Although this is a natural event, and we’re not aware of any link to human-induced climate change, this puts the ice shelf in a very vulnerable position,” Martin O’Leary, a Swansea University glaciologist and member of the MIDAS project team, said in a statement. “This is the furthest back that the ice front has been in recorded history. We’re going to be watching very carefully for signs that the rest of the shelf is becoming unstable.”

As for what will happen to this huge chunk of ice, nobody knows at the moment.

“The iceberg is one of the largest recorded and its future progress is difficult to predict,” Adrian Luckman of Swansea University, lead investigator of the MIDAS project, said in the statement. “It may remain in one piece, but is more likely to break into fragments. Some of the ice may remain in the area for decades, while parts of the iceberg may drift north into warmer waters.”

Editor’s Note: This article was updated to clarify when the rift in the ice sheet first showed up. 

Original article on Live Science.