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Scientists Have Discovered Vast Unidentified Structures Deep Inside the Earth – VICE UK

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This article originally appeared on VICE US.

Scientists have discovered a vast structure made of dense material occupying the boundary between Earth’s liquid outer core and the lower mantle, a zone some 3,000 kilometers (1,864 miles) beneath our feet.

The researchers used a machine learning algorithm that was originally developed to analyze distant galaxies to probe the mysterious phenomenon occurring deep within our own planet, according to a paper published on Thursday in Science.

One of these enormous anomalies, located deep under the Marquesas Islands, had never been detected before, while another structure beneath Hawaii was found to be much larger than previously estimated.

Scientists led by Doyeon Kim, a seismologist and postdoctoral fellow at the University of Maryland, fed seismograms captured from hundreds of earthquakes that occurred between 1990 to 2018 into an algorithm called Sequencer. While seismological studies tend to focus on relatively small datasets of regional earthquake activity, Sequencer allowed Kim and his colleagues to analyze 7,000 measurements of earthquakes—each with a magnitude of at least 6.5—that shook the subterranean world under the Pacific Ocean within the past three decades.

“This study is very special because, for the first time, we get to systematically look at such a large dataset that actually covers more or less the entire Pacific basin,” Kim said in a call. Though scientists have previously mapped out structures deep inside Earth, this study presents a rare opportunity to “bring everything in together and try to explain it in a global context,” he noted.

Earthquakes create seismic waves that travel through Earth’s interior where they become scattered and distorted by structures deep inside our planet. These warped patterns are captured in seismograms, which are recordings of wave activity inside Earth, enabling seismologists to capture rare glimpses of Earth’s inaccessible underworld.

The team focused on seismograms produced by shear (S) waves that travel along the boundary between Earth’s core and the lower portion of the mantle that borders it. These waves are the slower secondary waves that follow the initial tremors made by earthquakes, called primary (P) waves, and they generally produce clearer signals.

“We normally like to use S waves because they are larger in amplitude and the data is more or less clean because there is less P wave traffic,” said Kim. In particular, the team looked for the shear waves diffracting along the core-mantle boundary. “Because it diffracts along that surface, it’s a great phase to look for these tiny structures on top of the core-mantle boundary,” Kim noted.

When the shear waves hit these structures, they produce a type of echo-like signature known as a “postcursor” (there are helpful figures of this process on Kim’s website). These echoes indicate the presence of anomalies deep inside Earth called ultra low velocity zones (ULVZs), which are dense patches on the core-mantle boundary.

Nobody knows exactly how ULVZs are formed or what they are made of, but it’s clear that they have diameters of about a hundred kilometers and that they are dense enough to slow down waves that pass through them.

By running thousands of seismograms through Sequencer, Kim and his colleagues found that the strongest postcursor signals in their dataset emanate from under Hawai’i and the Marquesas Islands. This is tantalizing evidence of the existence of two “mega-ULVZs,” zones that stretch for about 1,000 kilometers, or more.

An updated map of Earth’s interior based on the new study. Image: D. Kim, V. Lekíc, B. Ménard, D. Baron and M. Taghizadeh-Popp

While the Hawaiian structure has been partially mapped out in previous studies, Kim’s team found that its dimensions are much larger than expected. Meanwhile, the mega-ULVZ detected under the Marquesas Islands represents “a previously unidentified localized wave-speed anomaly,” according to the study.

Mega-ULVZs are intriguing structures not only due to their size, but because they may be composed of exotic materials that date back to a time before Earth had a Moon. These huge anomalous chunks could be partially melted material that predate the Moon formation event, which scientists think was a gigantic collision between early Earth and a Mars-sized object more than four billion years ago.

“This is very interesting because this might indicate that mega-ULVZs are special and may host primitive geochemical signatures that have been relatively unmixed since early Earth history,” Kim said.

The new study demonstrates the applications of algorithms like Sequencer, which use a special type of process called unsupervised learning, in processing complex datasets like those found in astronomy, seismology, and countless other scientific fields. As opposed to supervised learning algorithms, which are trained to sort information based on known labels, unsupervised algorithms are designed to find insights in unlabelled datasets.

“What if we don’t really know what to look for in the dataset?” explained Kim. “This is the typical question we’d like to think about because the lower mantle, the target of our study, still has so many unknowns. It’s not really surprising to find almost anything in the lower mantle because we cannot actually go inside and take a look at it with our bare eyes.”

“When you use a sequencer, what it actually does is find additional information hidden behind this dataset,” he continued. “So, what we did here is find an optimal arrangement in the dataset itself. We’re not actually altering the dataset; we’re not doing anything but just rearranging and finding this optimal arrangement. That’s what Sequencer does.”

The team plans to continue developing this novel way of peering into Earth by examining higher-frequency waves that might yield finer details about the enigmatic structures on the core-mantle boundary. The researchers also hope to expand their dataset to seismograms produced under the Atlantic Ocean.

“We’re hoping that Sequencer will be able to basically let us use all of these diverse datasets and bring them together to look for these lower mantle structures systematically,” Kim concluded. “That is our vision going forward, to answer more questions about the lower mantle in general.”

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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