Village Covered in Film of Soot After Kamchatka Volcano Spews Ashes

A volcano in Russia’s Kamchatka region has spewed ashes, covering a local village with a thin layer of soot, the Emergency Situations Ministry said on Wednesday, the RIA Novosti news agency reported.


The ash cloud from the Shiveluch Volcano reached 6,500 meters above sea level, the ministry said in a statement, RIA Novosti reported. The volcano is 3,283 meters high.

Winds carried ashes nearly 50 kilometers east of the volcano, reaching the village of Ust-Kamchatsk, where a 1-millimeter layer of ash fallout was registered, the report said.

The incident presented no hazards to local residents’ health, the report said.

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Sydney’s Kurnell Declared A ‘Natural Disaster Zone’ After Tornado And Freak Storm

A freak thunderstorm and tornado has smashed Sydney ‘like a freight train’, ripping roofs off houses, blasting open office windows and flipping trucks on their sides with the strongest winds ever recorded in the state.


Kurnell, a Sutherland Shire suburb, was ground zero for the superstorm with tornado winds of 213km/h tearing through the area, the monster gale lifting trees by their roots and smashing some into homes.

On Wednesday afternoon, Bureau of Meteorology (BOM) announced on Twitter that the gusts were the strongest ever recorded by their equipment in NSW.
The city’s desalination plant in Kurnell was damaged with remnants of its insulation bats and roof sheeting caught in trees and wetlands, hundreds of metres from where they once were.

Hailstones battered the area and smashed car windscreens, and paramedics have treated two people for shock and one with head injury at an address near Sir Joseph Banks Drive.

Riot Squad police were helping distraught locals return to their damaged properties across the region. The entire suburb is without power and sewerage, and police say that may last until Thursday morning.

Emergency services have taken hundreds of calls and there are reports of multiple building collapses and even a truck tipped over in the wild winds.

Two of the worst hit areas by the tornado in Kurnell were Tasman and Bridges Streets.

One local, Frank Partlic, had just sold his home at 26 Tasman Street before it met with destruction.

It sold for a record $1.15million at auction on Tuesday afternoon – only for the tornado to destroy his renovated home of 17 years with six-months of pre-sale work behind it.

All that’s left is the walls, every room is inundated with roofing, sodden insulation and broken timber.

‘When it hit it was heavy rain and then this sheet of white like a fog came down,’ Mr Partlic told Daily Mail Australia.

‘Then it started, things coming off the roof, like a domino effect, and I had a look outside wondering where my daughter was and this huge black thing was flying through the air at me so I slammed the door.’

It was a trampoline flying at him from across the road.

‘I ran to the back because the roof started collapsing and when the back corner caved in, I tried to grab my wallet and iPad and find somewhere safe.
‘It went through and down to the gully and then turned back around and came again, like it was chasing me.’

Shane Hendricks, 28, was recovering at home from a broken rib with partner Ellie Warner when it swept in and ripped apart their home at 16 Tasman Street.
‘I had no idea, no warning,’ he told Daily Mail Australia.

‘It was swirling and came in hard ripping everything up.’

They took refuge in a bedroom with all their pets, including a horse, saving dozens of birds from a destroyed aviary, 12 dogs, guinea pigs and rabbits.

Natalie and Paul Hennessy on Bridges Street arrived home to find their home in tatters, holes in the roof, sodden carpets with broken glass and timber strewn through the rooms.

Other residents walked through the streets shell-shocked, stunned at the damage which had been wrought in such a short time.

‘It’s everything we worked up to, everything’s gone,’ Mrs Hennessy cried.

‘The ceilings have caved in, even the floors have collapsed, everything.

‘It’s everything we ever wanted – we had a brand new bathroom now look at it.

‘We were going to have Christmas here with the whole family, now where will we go?’

At one office complex in Kurnell the storm blasted the windows open, scattering files and trashing the room.

‘It was the winds — it sucked the windows out,’ worker Renee Celarc told Daily Mail Australia. ‘It was scary… we were all inside at the time.’

Local man Daniel Hipwell, who was working on a site in Green Hills in Cronulla said he and his colleagues watched the storm roll in.

‘Our blokes were all stuck in the machinery and had to stick it out,’ Mr Hipwell told Daily Mail Australia.

He said he heard reports that people in Kurnell are stuck in buildings which collapsed during the tornado, and a factory had its roof completely ripped off.

‘Some of us tried to head in to see if we could help… [but] they’ve closed the roads off and there’s a lot of emergency response, police and ambulances’ he said.

The rain soon let up in Kurnell, but residents were left stranded on Captain Cook Drive as police block all entrances to the site of a freak tornado.

Peter Myers, a Sutherland shire resident, said his daughters front windows ‘blew straight in’ on her and her three-month-old child.

The woman and her child have been evacuated along with other residents to the rural fire service headquarters in Martin Park.

Mr Myers said his neighbour’s boat flew onto his brand new car during the storm, destroying it.

It was a common experience.

‘My son had a boat parked in the driveway, and his boat disappeared – we found it on the other side of the road,’ said Kurnell resident Dianne Hennessy.

‘My son hasn’t been able to get home because he’s been at work. This is his house – he doesn’t even know what he’s coming home to.’

Roads to Kurnell are not expected to reopen until tonight, as powerlines and trees litter the road. Ausgrid and emergency services vehicles are still entering the area.

The desalination plant in Kurnell was evacuated after reportedly sustaining significant damage and workers were also cleared out of the Caltex refinery.

A Caltex spokeswoman said workers at the Kurnell refinery were evacuated as a safety precaution and there were no oil spills. She said the company was not aware of any injuries at the facility.

A 40-year-old man suffered head injuries in Kurnell and ambulance NSW said officers treated two other people.

They were all transferred to Sutherland Hospital in a stable condition.

There was chaos in the city’s east, too. Bondi Junction shopping centre was evacuated after parts of a roof collapsed. A woman, thought to be in her 60s, was taken to St Vincent’s Hospital in a stable condition for unknown trauma.

A balcony in Maroubra in Sydney’s eastern suburbs collapsed and the roof of a unit was damaged as storms travelled north.

Beth, who lives and works in Cronulla in the city’s south, said ‘golf ball-size hail’ fell on St Andrew’s Anglican Church.

‘We had some brown-outs, lots of thunder and lightning, and some large hail,’ she said.

‘The wind was strong and it was hitting our glass windows. I have a big dint in the front of my car.’

Sydney Airport was closely monitoring the storm activity with passengers being advised to check flight details with their airlines, an airport spokeswoman said.

Qantas has delayed some flights until the storm clears up.

BOM originally said severe thunderstorms would continue into the night with destructive winds, large hailstorms and very heavy rainfall.

But at around 5.30pm, the severe weather warning was cancelled, with the destructive winds moving offshore.

‘The immediate threat of severe thunderstorms has passed, but the situation will continue to be monitored and further warnings will be issued if necessary,’ BOM said in a statement of Sydney, Newcastle, Wollongong and surrounding areas.

However, shortly after 7pm, a severe thunderstorm warning was issued for the North West Slopes and Plains, Northern Tablelands and parts of the Northern Rivers, Mid North Coast, Central West Slopes and Plains and Upper Western Districts.

It warned of large hailstorms, heavy rainfall, flash flooding and damaging winds over the next few hours for Grafton, Coffs Harbour, Armidale, Tamworth, Moree and Lightning Ridge.

Meanwhile, it was fine and sunny in Melbourne on Wednesday with a maximum of 29 degrees. The city is expected to enjoy its first 40-degree December day since 2010 this weekend ahead of a four-day heatwave.

South Australia is also currently experiencing extremely warm weather – so hot in fact that international arrivals are being warned about the extreme heat and how to deal with it.

And across the pond it was set to swelter in parts of New Zealand, with temperatures in Christchurch forecast to hit a balmy 33 degrees.

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Storm Drops Up To 2 Feet On Colorado; 500 Flights Canceled

A powerful late-autumn storm dumped up to 24 inches of snow in the Colorado mountains on Tuesday before barreling onto the plains, prompting airlines to cancel about 500 flights at the Denver airport and leaving hundreds of miles of highways slippery with snow and ice.

Western Storms

Western Storms

The snow tapered off Tuesday afternoon as the storm moved northeast, leaving behind drifts up to four feet high.

“It’s going to be western Nebraska’s turn next,” National Weather Service meteorologist Todd Dankers said. “It’s going to end up eventually in Minnesota.”

It was the first big storm of the season for most of Colorado and Utah. Schools closed in some towns in at least four states.

Some flights at Denver International Airport were more than four hours late after at least seven inches of snow fell there, airport officials said.

More than 600 miles of Colorado Interstate highways were snowpacked or icy, and gusts as strong as 58 mph left near-whiteout conditions in isolated areas of Colorado’s eastern plains, Dankers said. Few highways were closed, however.

A snowplow slipped off a highway in the foothills west of Boulder early Tuesday and landed up-side-down in a creek, but the driver wasn’t injured.

The accident happened at about 4:30 a.m. in Boulder Canyon, said Amy Ford, a spokeswoman for the state Department of Transportation. Nothing spilled from the truck into the creek, she said. The cause of the accident was under investigation.

The wind piled up drifts three to four feet deep in the small northeastern Colorado town of Merino. Schools and the town offices were closed but some businesses opened as usual.

“I think we’re just more used to it,” said Jada Gettman, owner of Grandpa’s restaurant in Merino, which was open. “The snowing and blowing doesn’t affect us as much.”

About 24 inches of snow fell in the west-central mountains near McClure Pass, the National Weather Service said.

The town of Larkspur, in the foothills north of Colorado Springs, reported 17 inches of snow, and cities along the north-south Interstate 25 corridor reported up to a foot. Farther east, the Colorado plains received four to eight inches of snow.

The storm struck Utah before moving into Colorado, leaving about a foot of snow in the Salt Lake City area and more than two feet in other places.

The Utah Highway Patrol worked more than 400 accidents over the last two days as people struggled to get to work and school on icy, snow-packed roads.

The storm left a foot of snow in parts of Wyoming and Montana, leaving icy highways. School kids in Billings, Montana, the state’s largest city, got their first snow day in more than 25 years.

Parts of Interstates 25 and 80 were closed in Wyoming, but travel was a lot more fun in Yellowstone National Park, where recent snow allowed the park to start welcoming snowmobile and tank-like snowcoach traffic.

Elsewhere, rain and snow pushed into New England after an unseasonably warm and dry weekend. Sherman, Maine, reported six inches of snow at midday Tuesday.

Much of the West Coast was dry with below-average temperatures. The Tuesday morning low was -13 degrees in Bridgeport, California, and 6 degrees in Big Bear City, California.

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Evidence For More Recent Clay Formation On Mars Discovered

Recent orbital and rover missions to Mars have turned up ample evidence of clays and other hydrated minerals formed when rocks are altered by the presence of water. Most of that alteration is thought to have happened during the earliest part of Martian history, more than 3.7 billion years ago. But a new study shows that later alteration — within the last 2 billion years or so — may be more common than many scientists had thought.


The research, by Brown University geologists Ralph Milliken and Vivian Sun, is in press in the Journal of Geophysical Research: Planets.

The lion’s share of the clay deposits found on Mars thus far have turned up in terrains that date back to the earliest Martian epoch, known as the Noachian period. Clays also tend to be found in and around large impact craters, where material from deep below the surface has been excavated. Scientists have generally assumed that the clays found at impact sites probably formed in the ancient Noachian, became buried over time, and then were brought back to the surface by the impact.

That assumption is particularly true of clay deposits found in crater central peaks. Central peaks are formed when, in the aftermath of an impact, rocks from within the crust rebound upward, bringing layers to the surface that had been buried many kilometers deep.

“Because central peaks contain rocks uplifted from depth, some previous studies have assumed the clays found within central peak regions are uplifted too,” said Milliken, assistant professor of Earth, environmental and planetary sciences. “What we wanted to do was look at lots of these craters in detail to see if that’s actually correct.”

Milliken and Sun performed a survey of 633 crater central peaks distributed across the Martian surface. They looked at detailed mineralogy data collected by NASA’s Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), combined with high-resolution stereo images taken by NASA’s HiRISE camera. Both instruments fly aboard NASA’s Mars Reconnaissance Orbiter.

Of those 633 peaks, Milliken and Sun found 265 that have evidence of hydrated minerals, the majority of which were consistent with clays. The researchers then used HiRISE images to establish a detailed geologic context for each of those craters to help determine if the clays were in rocks that had indeed been excavated from depth. They found that in about 65 percent of cases the clay minerals were indeed associated with uplifted bedrock.

“That’s a majority,” Milliken said, “but it still leaves a substantial number of craters — 35 percent — where these minerals are present and not clearly associated with uplift.”

Within those 35 percent, Milliken and Sun found examples where clays exist in dunes, unconsolidated soil, or other formations not associated with bedrock. In other cases, clays were found in impact melt — deposits of rock that had been melted by the heat of the impact and then re-solidified as it cooled. Both of these scenarios suggest that the clay minerals at these sites are likely “authigenic,” meaning they formed in place sometime after impact occurred, rather than being excavated from underground.

In a number of cases, these authigenic clays were found in fairly young craters, ones formed in the last 2 billion years or so.

“What this tells us is that the formation of clays isn’t restricted to the most ancient time period on Mars,” Milliken said. “You do apparently have a lot of local environments in these crater settings where you can still form clays, and it may have occurred more often than many people had thought.”

One mechanism for forming these clays could be related to the impact process itself, the researchers say. Impacts generate heat, which could melt any ice or pre-existing hydrated minerals that may have been present within the nearby crust. Any liberated water could then percolate through surrounding rock to form clays. Some impact simulations suggest that these hydrothermal conditions could persist for perhaps thousands of years, making for potentially habitable conditions.

And that could have implications for the search for evidence of past life on Mars.

“So far, much of our surface exploration by rovers has focused on ancient terrains and whether or not the environments they record were habitable,” said Sun, lead author on the study and a graduate student working with Milliken. “But if we wanted to look at an environment that was more recent, we’ve identified craters that might be possible candidates.”

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NASA Telescopes Detect Jupiter-Like Storm On Small Star

Astronomers have discovered what appears to be a tiny star with a giant, cloudy storm, using data from NASA’s Spitzer and Kepler space telescopes. The dark storm is akin to Jupiter’s Great Red Spot: a persistent, raging storm larger than Earth.


“The star is the size of Jupiter, and its storm is the size of Jupiter’s Great Red Spot,” said John Gizis of the University of Delaware, Newark. “We know this newfound storm has lasted at least two years, and probably longer.” Gizis is the lead author of a new study appearing in The Astrophysical Journal.

While planets have been known to have cloudy storms, this is the best evidence yet for a star that has one. The star, referred to as W1906+40, belongs to a thermally cool class of objects called L-dwarfs. Some L-dwarfs are considered stars because they fuse atoms and generate light, as our sun does, while others, called brown dwarfs, are known as “failed stars” for their lack of atomic fusion.

The L-dwarf in the study, W1906+40, is thought to be a star based on estimates of its age (the older the L-dwarf, the more likely it is a star). Its temperature is about 3,500 degrees Fahrenheit (2,200 Kelvin). That may sound scorching hot, but as far as stars go, it is relatively cool. Cool enough, in fact, for clouds to form in its atmosphere.

“The L-dwarf’s clouds are made of tiny minerals,” said Gizis.

Spitzer has observed other cloudy brown dwarfs before, finding evidence for short-lived storms lasting hours and perhaps days.

In the new study, the astronomers were able to study changes in the atmosphere of W1906+40 for two years. The L-dwarf had initially been discovered by NASA’s Wide-field Infrared Survey Explorer in 2011. Later, Gizis and his team realized that this object happened to be located in the same area of the sky where NASA’s Kepler mission had been staring at stars for years to hunt for planets.

Kepler identifies planets by looking for dips in starlight as planets pass in front of their stars. In this case, astronomers knew observed dips in starlight weren’t coming from planets, but they thought they might be looking at a star spot — which, like our sun’s “sunspots,” are a result of concentrated magnetic fields. Star spots would also cause dips in starlight as they rotate around the star.

Follow-up observations with Spitzer, which detects infrared light, revealed that the dark patch was not a magnetic star spot but a colossal, cloudy storm with a diameter that could hold three Earths. The storm rotates around the star about every 9 hours. Spitzer’s infrared measurements at two infrared wavelengths probed different layers of the atmosphere and, together with the Kepler visible-light data, helped reveal the presence of the storm.

While this storm looks different when viewed at various wavelengths, astronomers say that if we could somehow travel there in a starship, it would look like a dark mark near the polar top of the star.

The researchers plan to look for other stormy stars and brown dwarfs using Spitzer and Kepler in the future.

“We don’t know if this kind of star storm is unique or common, and we don’t why it persists for so long,” said Gizis.

Other authors of the study are: Adam Burgasser–University of California, San Diego; Kelle Cruz, Sara Camnasio and Munazza Alam–Hunter College, New York City, New York; Stanimir Metchev–University of Western Ontario, Canada; Edo Berger and Peter Williams–Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts; Kyle Dettman–University of Delaware, Newark; and Joseph Filippazzo–College of Staten Island, New York.

NASA’s Ames Research Center in Moffett Field, California, manages the Kepler and K2 missions for NASA’s Science Mission Directorate. JPL managed Kepler mission development. Ball Aerospace & Technologies Corp. operates the flight system with support from the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.

JPL manages the Spitzer Space Telescope mission for NASA. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Company, Littleton, Colorado. Data are archived at the Infrared Science Archive housed at the Infrared Processing and Analysis Center at Caltech.

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A ‘Ghost From The Past’ Recalls The Infancy Of The Milky Way

When our galaxy was born, around 13 billion years ago, a plethora of clusters containing millions of stars emerged. But over time, they have been disappearing. However, hidden behind younger stars that were formed later, some old and dying star clusters remain, such as the so-called E 3. European astronomers have now studied this testimony to the beginnings of our galaxy.

milky way

Globular clusters are spherical-shaped or globular stellar groupings — hence its name- which can contain millions of stars. There are about 200 of them in the Milky Way, but few are as intriguing to astronomers as the E 3 cluster.

It is situated around 30,000 light years away, in the southern constellation of Chameleon. A team of Spanish and Italian astronomers have named it “a ghost from the Milky Way’s past” in an article published recently in the Astronomy & Astrophysics journal.

“This globular cluster, and a few similar ones — such as Palomar 5 or Palomar 14 — are `ghosts´ because they appear to be in the last stages of their existence, and we say ´from the past´ because they are very old. They were formed when our galaxy was virtually new-born, 13 billion years ago,” says one of the authors, Carlos de la Fuente Marcos.

E 3 is hidden behind younger and brighter objects located between the cluster and Earth, but it has been possible to analyse it thanks to the Very Large Telescope (VLT) held in the European Southern Observatory (ESO) in Cerro Paranal, Chile. The data obtained revealed some surprises.

“Unlike typical globular clusters, which contain hundreds of thousands and in some cases millions of stars, the object studied only has a few tens of thousands of them,” says De la Fuente Marcos. “Additionally, it doesn’t have the typical circular symmetry, but a much distorted, almost ghostly, rhomboidal shape, contorted by the galactic gravitational waves.”

According to another study on E 3 by Michigan State University (USA) researchers, published in The Astrophysical Journal, this cluster is chemically homogeneous, that is, it doesn’t have several star populations in its interior.

“This is characteristic of an object that was created in block, in one single episode, like what is supposed to have happened when our galaxy was born: very large star clusters (containing millions of stars) were formed, but what remains of them today are objects like E 3, ghosts from a distant past,” says De la Fuente Marcos. He explains that the study of these objects “enables us to gain insight into the infancy of the Milky Way.”

Native or captured?

Despite the recently published new data on this strange globular cluster, astronomers still have to clarify if it was really formed in our galaxy or not. It is known that some of its clusters are not native to the Milky Way, but were captured, even though they can currently be seen in its interior. Long ago, our galaxy cannibalised other smaller galaxies and kept their globular clusters. The rest were formed in-situ.

In the article, it is suggested that the object analysed could be dynamically related to other clusters, such as 47 Tucanae, one of the richest and largest of the Milky Way. They could even share the same stream of stars. If this were the case, it would support the hypothesis that E 3 was captured in the distant past.

“We hope to obtain new data in 2016, thanks to more spectroscopic observations, and perhaps we will be able to give answers to these questions,” says De la Fuente Marcos, an independent astronomer who collaborates with colleagues from the Northern Catholic University and ESO in Chile, and the University of Padua, Italy.

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First Explanations For Boundary Within Earth’s Mantle

Earth’s mantle, the large zone of slow-flowing rock that lies between the crust and the planet’s core, powers every earthquake and volcanic eruption on the planet’s surface. Evidence suggests that the mantle behaves differently below 1 megameter (1,000 kilometers, or 621 miles) in depth, but so far seismologists have not been able to explain why this boundary exists.


Two new studies co-authored by University of Maryland geologists provide different, though not necessarily incompatible, explanations. One study suggests that the mantle below 1 megameter is more viscous–meaning it flows more slowly–than the section above the boundary. The other study proposes that the section below the boundary is denser–meaning its molecules are more tightly packed–than the section above it, due to a shift in rock composition.

Taken together, the studies provide the first detailed look at why large-scale geologic features within the mantle behave differently on either side of the megameter divide. The papers were published on December 11, 2015, in the journals Science and Science Advances.

“The existence of the megameter boundary has been suspected and inferred for a while,” said Vedran Lekic, an assistant professor of geology at UMD and co-author of the Science paper that addresses mantle viscosity. “These papers are the first published attempts at a detailed explanation and it’s possible that both explanations are correct.”

Although the mantle is mostly solid, it flows very slowly in the context of geologic time. Two main sources of evidence suggest the existence of the megameter boundary and thus inspired the current studies.

First, many huge slabs of ocean crust that have been dragged down, or subducted, into the mantle can still be seen in the deep Earth. These slabs slowly sink downward toward the bottom of the mantle. A large number of these slabs have stalled out and appear to float just above the megameter boundary, indicating a notable change in physical properties below the boundary.

Second, large plumes of hot rock rise from the deepest reaches of the mantle, and the outlines of these structures can be seen in the deep Earth as well. As the rock in these mantle plumes flows upward, many of the plumes are deflected sideways as they pass the megameter boundary. This, too, indicates a fundamental difference in physical properties on either side of the boundary.

“Learning about the anatomy of the mantle tells us more about how the deep interior of Earth works and what mechanisms are behind mantle convection,” said Nicholas Schmerr, an assistant professor of geology at UMD and co-author of the Science Advances paper that addresses mantle density and composition. “Mantle convection is the heat engine that drives plate tectonics at the surface and ultimately leads to things like volcanoes and earthquakes that affect people living on the surface.”

The physics of the deep Earth are complicated, so establishing the mantle’s basic physical properties, such as density and viscosity, is an important step. Density refers to the packing of molecules within any substance (gas, liquid or solid), while viscosity is commonly described as the thickness of a fluid or semi-solid. Sometimes density and viscosity correlate with each other, while sometimes they are at odds. For example, honey is both more viscous and dense than water. Oil, on the other hand, is more viscous than water but less dense.

In their study, Schmerr, lead author Maxim Ballmer (Tokyo Institute of Technology and the University of Hawaii at Manoa) and two colleagues used a computer model of a simplified Earth. Each run of the model began with a slightly different chemical composition–and thus a different range of densities–in the mantle at various depths. The researchers then used the model to investigate how slabs of ocean crust would behave as they travel down toward the lower mantle.

In the real world, slabs are observed to behave in one of three ways: The slabs either stall at around 600 kilometers, stall out at the megameter boundary, or continue sinking all the way to the lower mantle. Of the many scenarios for mantle chemical composition the researchers tested, one most closely resembled the real world and included the possibility that slabs can stall at the megameter boundary. This scenario included an increased amount of dense, silicon-rich basalt rock in the lower mantle, below the megameter boundary.

Lekic, lead author Max Rudolph (Portland State University) and another colleague took a different approach, starting instead with whole-Earth satellite measurements. The team then subtracted surface features–such as mountain ranges and valleys–to better see slight differences in Earth’s basic shape caused by local differences in gravity. (Imagine a slightly misshapen basketball with its outer cover removed.)

The team mapped these slight differences in Earth’s idealized shape onto known shapes and locations of mantle plumes and integrated the data into a model that helped them relate the idealized shape to differences in viscosity between the layers of the mantle. Their results pointed to less viscous, more free-flowing mantle rock above the megameter boundary, transitioning to highly viscous rock below the boundary. Their results help to explain why mantle plumes are frequently deflected sideways as they extend upward beyond the megameter boundary.

“While explaining one mystery–the behavior of rising plumes and sinking slabs–our results lead to a new conundrum,” Lekic said. “What causes the rocks below the megameter boundary to become more resistant to flow? There are no obvious candidates for what is causing this change, so there is a potential for learning something fundamentally new about the materials that make up Earth.”

Lekic and Schmerr plan to collaborate to see if the results of both studies are consistent with one another–in effect, whether the lower mantle is both dense and viscous, like honey, when compared with the mantle above the megameter boundary.

“This work can tell us a lot about where Earth has been and where it is going, in terms of heat and tectonics,” Schmerr said. “When we look around our solar system, we see lots of planets at various stages of evolution. But Earth is unique, so learning what is going on deep inside its mantle is very important.”

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