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

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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.

New Island Pops Up Off the Coast of North Carolina


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New Island Pops Up Off the Coast of North Carolina

New Island Pops Up Off the Coast of North Carolina
A new sandbar island has cropped up over the past few months just off the coast of North Carolina. Photographer Chad Koczera couldn’t get to the island on foot, so he sent a drone into the skies to capture this stunning image of the newly-formed island.

Credit: Courtesy of Chad Koczera

A new island suddenly emerged from the sea just off the coast of North Carolina — but officials warn that the spit of land is too dangerous for humans to explore.

The new sandbar island seemingly sprang from the ocean in just a few weeks, the Virginian Pilot reported. The island, which is about 1 mile (1.6 kilometers) long and about 480 feet (146 meters) wide, lies off the coast of Buxton, North Carolina, which is part of the Cape Hatteras National Seashore.

The new island grew from a mere nubbin in the ocean in April to its current size over Memorial Day weekend. One of the early explorers of the island, Janet Regan, took her 11-year-old son there to collect seashells. Because of its treasure trove of shells, the boy named it Shelly Island, the Pilot reported. [See Images of a Volcanic Island Birthed in Japan]

While the newborn island may be tantalizing for would-be explorers, it’s also very dangerous, Bill Smith, president of the North Carolina Beach Buggy Association, told the Pilot. Officials with the Cape Hatteras National Seashore have warned people not to try to reach the island.

Because the island formed near a popular fishing spot, years’ worth of fishing hooks could be lurking just below the sand. Sharks and stingrays prowl just beneath the water’s surface in the area, and the narrow 50-foot (15 m) strip of water between the island and the mainland forms a little “river” that creates a strong rip current, he said.

“We’re worried about shark bites, but we’re more worried about drownings,” Smith said.

The sandbar isn’t accessible by foot, so photographer Chad Koczera sent a drone into the skies to capture a stunning aerial photo. More intrepid (or foolhardy) explorers also have tried to reach the island by boat or paddleboard, the Pilot reported.

The area of coastline near the island is always transforming, according to a statement from the Cape Hatteras National Seashore. The point, called Cape Point, sometimes changes orientation, and currents and storms are constantly shaping the land. It’s likely that such forces formed the sandbar, meaning it could get even bigger or sink beneath the waves in the next year or two, Smith said.

If anyone does attempt a trip to the island, National Seashore Superintendent David Hallac said such a trip “is best accomplished by experienced kayakers or paddle boarders that are using appropriate flotation and mindful of the tides and strong currents in the area.”

Originally published on Live Science

Photos of Siberia’s Mysterious Craters


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Photos of Siberia’s Mysterious Craters

Seven giant craters have mysteriously appeared in northern Siberia, possibly due to methane gas released from melting permafrost. Check out these jaw-dropping photos of the strange geological structures. [Read full story about the Siberian craters]

This crater, in the Yamal Peninsula, was discovered in 2014 by helicopter pilots 19 miles (30 kilometers) from Bovanenkovo, a major gas field in the Yamalo-Nenets autonomous district. (Image credit: Marya Zulinova/The Siberian Times)


Four Arctic craters can be seen in this satellite image: B1, the famous Yamal hole located 19 miles (30 kilometers) from Bovanenkovo; B2, the recently discovered crater located 6.2 miles (10 km) south of Bovanenkovo; B3, a crater located 56 miles (90 km) from Antipayuta village; and B4, a crater located near Nosok village, north of the Krasnoyarsk region near Taymyr Peninsula. (Image credit:Vasily Bogoyavlensky)

Satellite image of the site before the formation of the Yamal hole (B1). K1 and the red outline show the hillock formed before the emission of methane gas. Yellow outlines show potentially dangerous areas where gas could erupt. (Image credit: Marya Zulinova/The Siberian Times)


Satellite images showing a mound of Earth before the gas emission that formed crater B2 (top). Lakes formed at a couple of the craters, and more than 20 smaller craters were found nearby (bottom). (Image credit: Marya Zulinova/The Siberian Times)


The Yamal lake showing signs of gas emission. (Image credit: Marya Zulinova/The Siberian Times)


Crater B3, located 56 miles (90 km) from Antipayuta village, Yamal district (top). Crater B4, located near Nosok village, north of the Krasnoyarsk region, near Taymyr Peninsula. (Image credit: local residents/The Siberian Times)


The ring of soil around these craters suggests an underground explosion. (Image credit: Vasily Bogoyavlensky/The Siberian Times)


The Russian Center of Arctic Exploration embarked on an expedition to Yamal crater in early November 2014. The researchers were the first in the world to climb down into the crater. (Image credit: Vladimir Pushkarev/The Siberian Times)

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Oozing Methane Blasts Holes in Siberian Tundra


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Oozing Methane Blasts Holes in Siberian Tundra

A crater on the Yamal Peninsula in Siberia, reported in the spring of 2017.

Credit: Itar-Tass/Zuma

Escaping methane gas has blown at least two new holes in the Siberian tundra in the past few months, according to eyewitness accounts to the Siberian Times and the Russian Academy of Sciences.

Reindeer herders northwest of the village of Seyakha in Siberia’s far north reported seeing an eruption of fire and smoke on the morning of June 28 — an event caught on seismic sensors at 11 a.m. local time, according to The Siberian Times. Scientists visiting the site photographed a fresh crater blown into the banks of a river.

Researchers also discovered a second, previously unknown crater in the Tyumen region of Siberia this month, the newspaper reported. Local herders told Aleksandr Sokolov, a researcher at the Institute of Ecology of Plants and Animals in Russia, that they’d observed fire in the area of that crater in the winter or early spring.

When permafrost melts, it releases large amounts of methane. According to Russian scientists, this sudden release could have led to the explosions. How fast and how frequently this is happening remain controversial topics in the scientific community, given that Siberia is so remote and unexplored. But scientists do agree that Siberia’s permafrost is in danger of melting as the globe warms.

Permafrost is soil that stays frozen all year long. Any organic matter, like dead grass or animal corpses, caught up in permafrost stays frozen, too. But as the Arctic warms, the depth of the spring thaw gets deeper and deeper — a process called active-layer deepening. As the soil thaws, the organic material locked inside begins to decompose all at once, releasing flammable gases such as methane, University of Michigan postdoctoral researcher Ben Abbott told Live Science in March.

In some cases, this release is slow, Abbott said. Other times, the soil can collapse dramatically, creating features called thermokarsts. These can look like landslides, slumps, pits or craters. Some fill with water and become lakes.

Past research suggests that warming can cause explosive changes in the landscape. A study released in June found that at least 100 giant cratersformed in one region on the Arctic seafloor about 11,600 years ago as the ice sheet retreated and destabilized mounds of frozen methane underneath. These mounds, call pingos, sometimes blew craters up to 0.6 miles (1 kilometer) wide into the ocean bottom.

Some Arctic scientists think something similar is happening in Siberia today. Pingos, or soil-covered permafrost hills, occur on land, too. If they melt rapidly, they could release a fiery burst of methane and create craters similar to the ancient ones seen on the seafloor. Previously, Siberian researchers had discovered craters that had never been seen before, but they had not published any information on the ages of the craters or scientific analyses of how they’d formed. The new eyewitness accounts from local herders suggest that the formation of these craters may, indeed, be violent.

Though the region of Siberia where these craters are located is remote, Russian authorities are concerned about the explosions caused by melting permafrost. The crater that formed on June 28 is about 60 miles (100 km) from Sabetta, a newly developed port on the Ob River that’s used to transport liquefied natural gas from the Yuzhno-Tambeyskoye gas field, The Siberian Times reported.

“It is very important for us also to know what to do, because such an eruption can occur anywhere,” Alexander Mazharov, deputy governor of the Yamalo-Nenets autonomous region in Siberia, told The Siberian Times. “It might hit a technical facility, a residential settlement or a linear object,” he said, referring to a pipeline or railroad.

Original article on Live Science. 

 

Why Are the Vermilion Cliffs So Red?


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Why Are the Vermilion Cliffs So Red?

The red Vermillion Cliffs of Arizona

Credit: tobkatrina/Shutterstock

If you’ve ever visited the Grand Canyon, Arizona’s Vermillion Cliffs or the astonishingly rainbow-colored hills of China’s Zhangye National Geopark, you likely noticed they have one thing in common: red-colored rocks.

How did these rocks get so red? The answer involves iron, which bonds with other elements to form minerals famous for their red, rusty hue.

To start at the beginning, the iron on Earth came from ancient supernova events, the collapse of large stars that ran out of energy and “died.” After these stars collapsed (due to extreme gravity at their centers), they released a vast amount of new energy, which fused together elements, creating heavier elements, including iron (Fe).

After the force from such a collapse got too immense, the collapsing star exploded outward, sending the elements into space, said Jessica Kapp, a senior lecturer and associate department head of the geosciences department at the University of Arizona. [Photo Timeline: How the Earth Formed]

“When Earth first formed, it grabbed up a bunch of these elements from the space around it, including iron,” Kapp told Live Science in an email.

In Earth’s early history, during the Archean era (4 billion to 2.5 billion years ago), there was little oxygen in the atmosphere. Without oxygen, iron can dissolve in water, and so Earth’s early Archean oceans carried large amounts of dissolved iron, said Terry Engelder, a professor of geosciences at Pennsylvania State University.

However, single-celled organisms began producing oxygen through photosynthesis — a process that uses sunlight to power a reaction between water and carbon dioxide, leading to the creation of carbohydrates and oxygen.

That oxygen got into the oceans and bonded with the iron, leading to the creation of iron-oxide minerals, such as hematite (Fe2O3), which is often red in color, and magnetite (Fe3O4).

“An oxidation reaction you might be familiar with is rusting — when metal reacts with the oxygen in the air and becomes rust,” Kapp said. “In rocks, it is little grains of minerals like hematite and magnetite that have iron in them. Those minerals experience oxidation and become rust, turning the rocks red.”

The creation of these minerals led to the formation of the banded iron formations, the most important iron deposits in the world, Engelder said. The formations are “banded” because they contain layers of hematite between layers of silica, which were laid down as sedimentary rock layers during the during the late Archean to mid-Proterozoic (an era lasting from 2.5 billion to 541 million years ago), according to a 2016 study in the journal Geoscience Frontiers.

The Danxia Rainbow Mountains, located within the National Geopark of Zhangye in China.

The Danxia Rainbow Mountains, located within the National Geopark of Zhangye in China.

Credit: Kattiya.L/Shutterstock

For instance, banded iron formations appear in Carajas, Brazil; Lake Superior, Canada; Hamersley Basin, Western Australia; regions in northern China; and the Mesabi Iron Range in Minnesota.

In the case of the Vermilion Cliffs in Arizona, the red color comes from iron-rich minerals that are interspersed with the sedimentary rock at that site.

“Red sandstones are very common in the western United States,” Kapp said. “[They] can be found in places like Sedona, Arizona, and in the Mojave Desert of California at Red Rock Canyon State Park.”

Other red rock formations that contain oxidized iron minerals include the Chugwater Formation in Wyoming, Montana and Colorado and theRedwall Limestone cliff of the Grand Canyon, which was stained red by the iron-oxide minerals leaching out from the layers above it.

Original article on Live Science.