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Earth’s core is leaking, scientists say

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Scientists have detected a surprising amount of a rare version of helium, called helium-3, in volcanic rocks on Canada’s Baffin Island, lending support to the theory that the noble gas is leaking from Earth’s core — and has been for millennia.

The research team also detected helium-4 within the rocks.

While helium-4 is common on Earth, helium-3 is more readily found elsewhere in the cosmos, which is why scientists were surprised to detect a larger amount of the element than had been previously reported from the rocks on Baffin Island. A study describing the discovery published recently in the journal Nature.

“At the most basic level, there is little 3He (helium-3) in the universe compared to 4He (helium-4),” said lead study author Forrest Horton, associate scientist in the department of geology and geophysics at Woods Hole Oceanographic Institution, in an email.

“3He is rare in Earth because it has not been produced in or added to the planet in significant quantities and it is lost to space,” Horton added. “As Earth’s rocky portion stirs and convects like hot water on a stove top, material ascends, cools, and sinks.

During the cooling stage, helium is lost to the atmosphere and then to space.”

Detecting elements that leak from Earth’s core can help scientists unlock insights into how our planet formed and evolved over time, and the new findings provide evidence to bolster an existing hypothesis about how our planet came to be.

A TROVE OF ‘SCIENTIFIC TREASURES’

Baffin Island, located in the territory of Nunavut, is the largest island in Canada. It’s also the fifth-largest island in the world.

A high ratio of helium-3 to helium-4 was first detected in Baffin Island volcanic rocks by Solveigh Lass-Evans as part of her doctoral studies under the supervision of University of Edinburgh scientist Finlay Stuart. Their findings were published in Nature in 2003.

The composition of a planet is a reflection of the elements that formed it, and previous research found that trace amounts of helium-3 leaking from Earth’s core supports the popular theory that our planet originated in a solar nebula — a cloud of gas and dust that likely collapsed due to the shock wave of a nearby supernova — which contained the element.

Horton and his colleagues took it a step further when they conducted research on Baffin Island in 2018, studying the lava that erupted millions of years ago when Greenland and North America split apart, making way for a new seafloor. They wanted to investigate the rocks that may contain insights about the contents locked within Earth’s core and mantle, the mostly solid layer of Earth’s interior located beneath its surface.

The researchers travelled by helicopter to reach the remote, otherworldly landscape of the island, where lava flows have formed towering cliffs, giant icebergs float by and polar bears stalk the coastline. Local organizations, including the Qikiqtani Inuit Association and Nunavut Research Institute, provided the researchers with access, advice and protection from the bears, Horton said.

“This area on Baffin Island holds special importance both as sacred lands for the local communities and as a scientific window into the deep Earth,” he said.

The Arctic rocks that Horton and his team investigated revealed surprisingly higher measurements of helium-3 and helium-4 than was reported by previous research, and the measurements varied among the samples they collected.

“Many of the lavas are full of bright green olivine (also known as the gemstone peridot), so breaking off fresh pieces with a rock hammer was as thrilling as breaking apart geodes as a kid: each rock was a treasure to be discovered,” Horton said. “And what scientific treasures they turned out to be!”

Only about one helium-3 atom exists for every million helium-4 atoms, Horton said. The team measured about 10 million helium-3 atoms per gram of olivine crystals.

“Our high 3He/4He measurements imply that gases, presumably inherited from the solar nebula during solar system formation, are better preserved in Earth than previously thought,” he said.

TRACING EARTH’S HISTORY

But how did the helium-3 end up in the rocks in the first place?

The answer may begin as far back as the big bang, which, when it created the universe, also released an abundance of hydrogen and helium. These elements were incorporated into the formation of galaxies over time.

Scientists believe our solar system formed 4.5 billion years ago within a solar nebula. As the dust cloud collapsed in a supernova, the resulting material formed a spinning disk that eventually gave rise to our sun and the planets, according to NASA.

Helium inherited from the solar nebula likely became locked in Earth’s core as the planet formed, making the core a reservoir of noble gases. As helium-3 leaked from the core, it ascended to the surface through the mantle in the form of magma plumes that eventually erupted on Baffin Island.

“During the eruption, the vast majority of the gases in the magma escaped to the atmosphere,” Horton said. “Only the olivine crystals that grew prior to eruption trapped and preserved the helium from the deep Earth.”

The new research supports the idea that helium-3 is leaking from Earth’s core and has been for some time, but the researchers aren’t entirely sure when this process began.

“The lavas are about 60 million years old, and the ascent of the mantle plume took perhaps tens of millions of years,” Horton said. “So, the helium we measured in these rocks would have escaped the core perhaps 100 million years ago or possibly much earlier.”

Helium leaking from Earth’s core doesn’t affect our planet or have any negative implications, he said. The noble gas does not chemically react with matter, so it won’t have an impact on humanity or the environment.

Next, the research team wants to investigate whether the core is a storehouse of other light elements, which could account for the why Earth’s outer core is less dense than expected.

“Is the core a major repository of elements like carbon and hydrogen, which are so important in terms of planetary habitability? If so, have fluxes of these elements from the core over (Earth’s) history influenced planetary evolution? I am excited to investigate links between helium and other light elements,” Horton said. “Perhaps helium can be used to track other elements across the core-mantle boundary.”

 

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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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