Nothing is quite as joyful as watching a dog get caught up in a bout of “zoomies,” zipping around a living room or backyard in a burst of energy. But our canine pals aren’t the only animals subject to these hyperactive displays.
Young condors can also engage in zoomies, as demonstrated in a recent Facebook post from the Ventana Wildlife Society in California. The video shows clips of two young California condors (Gymnogyps californianus), Chert and Pumice, seemingly having a blast in their release pen.
“We observe the zoomies in both captive and wild condors. It’s just a sudden expression of pure excitement for young condors and very fun to watch,” Joe Burnett, California Condor Recovery Program Manager at the wildlife society, tells Popular Science. “Zoomies come out of nowhere and they just can’t contain themselves and totally let loose. They hop, run in circles, or flap around, or all the above! It’s just pure fun!”
It’s not just about the fun, however. Zoomies allow the young condors to release energy and grow stronger, as well as help them figure out their wings, according to the team.
The two zoomie condors are 1.5-year-old males who were raised in zoos before arriving at Ventana Wildlife Society’s San Simeon release pen in early September. It’s called a release pen because Chert, Pumice, and three other captive condors will be kept in the pen to acclimate until their release on October 24 at 10 a.m. The release will also be livestreamed.
The quintet will become a part of the wild condor population of central California, which today includes 104 individuals. But it won’t be a total goodbye. Scientists will be able to keep an eye on Pumice and Chert’s locations via wing-mounted radio & GPS transmitters and ID tags.
California condors are North America’s largest land bird. They measure 9.5 feet from wing tip to wing tip. But their size didn’t spare them from a precipitous population drop. In 1982 there were only 23 condors left in the world. All wild condors were captured and included in a captive breeding program.
“Condor releases are critical to achieving our ultimate goal- to reestablish a self-sustaining condor population in the wild,” Burnett concludes.
At the end of 2025, there were 607 California condors. We’d say Pumice and Chert earned their right to party.
The post Condors get the ‘zoomies’ too appeared first on Popular Science.
The Ojai Raptor Center released the final necropsy results for Jackie, an internet-famous bald eagle mother who was in their care this summer. Jackie was brought into the bird rehabilitation center weak and dehydrated following an altercation with another eagle in July.
Officially designated as Patient 26-519, Jackie’s necropsy revealed a “complex and unusual disease process involving severe, chronic inflammation and ulceration of the stomach, persistent internal bleeding, anemia and secondary bacterial sepsis.” She was also diagnosed with Highly Pathogenic Avian Influenza (HPAI) commonly called bird flu, which was behind severe stomach ulceration. Raptors (eagles, hawks, falcons, owls, etc.) are highly susceptible to the virus
All of these medical complications developed over time and ultimately contributed to her death on August 10.
“These findings have helped connect many of the pieces we were seeing throughout her hospitalization and provided a better understanding of the challenges she faced,” the Ojai Raptor Center wrote. “We are grateful to the many veterinary specialists, laboratories, wildlife agencies and partner organizations who worked alongside our team to understand her illness and provide her with the best possible care. Caring for her was an extraordinary privilege for our entire team.”
The full report can be read in Jackie’s veterinary medical journal. The necropsy was preformed by veterinary pathologists at the San Diego Zoo Wildlife Alliance.
Friends of Big Bear Valley (FOBBV), the non-profit organization that runs the live cameras where viewers from all over the world watched Jackie and her partner Shadow, said that they will follow up with their thoughts once their team has had time to process the report.
“The story of the Big Bear bald eagle reflects the powerful connection people feel to these iconic birds,” California Department of Fish and Wildlife Director Meghan Hertel added. “We’re grateful to everyone who cared for her and worked to support her well-being. Understanding the results of these tests is an important part of learning from this case and can help inform the care and treatment of other eagles and wildlife in the future.”
Jackie was born, raised, and lived in Big Bear Valley in Southern California. Prior to the 2011-2012 nesting season, no bald eagle chicks were known to have ever hatched in Big Bear Valley. Then came Jackie, named after a forest ranger and born to parents Ricky and Lucy in 2012.
During the 2016-2017 nesting season, Jackie took over a nest where Friends of Big Bear Valley (FOBBV) had a camera stationed. In 2018, she had two chicks named Stormy and Big Bear Baby (or BBB) with her first mate, Mr. B.
Her long-time partner Shadow entered the picture in summer 2018. He showed up at the nest and would not leave. FOBBV called the new male Shadow because he appeared so determined to stay in the nest, and the team initially believed he was one of Jackie’s siblings, also named Shadow. The eagle’s plumage indicated he was one year older than the other Shadow and not Jackie’s sibling, but the name stuck.
Shadow continued to hold his ground and Mr. B gave up and eventually left. Jackie then accepted Shadow as her new mate.
Wildlife cameras documented Jackie and Shadow’s life together, offering viewers a direct look into the brutality and beauty of nature. The pair successfully raised chicks in 2019 (Cookie and Simba) and 2022 (Spirit). The pair’s eggs failed to hatch in 2023 and 2024. In 2025, Jackie laid three eggs that all hatched in early March. However, a strong snowstorm dumped up to two feet of snow and battered the nest with strong wind and only two of the chicks (Sunny and Gizmo) survived.
In January, Jackie laid two eggs in the nest, but ravens destroyed them. She later laid two more eggs that hatched in April and named Luna and Sandy. The name Sandy is in honor of FOBBV’s former executive director Sandy Steers who died from cancer in February.
On July 17, Jackie was found injured on the ground near Dana Point Park, California. Cell phone video from a witness confirmed that she had an altercation with two other subadult eagles. She successfully fended off the other eagles by turning over and using her talons, but could not fly far away.
She was transferred to the Ojai Raptor Center, where she was diagnosed with severe anemia. Her anemia worsened during the first week of August, the Ojai Raptor Center said that she was in unstable condition on August 9. Her packed cell volume (PCV) fell below percent, before rising to nine percent.
On July 17, Jackie was found injured on the ground near Dana Point Park, California. Cell phone video from a witness confirmed that she had an altercation with two other subadult eagles. She successfully fended off the other eagles by turning over and using her talons, but could not fly far away.
She was transferred to the Ojai Raptor Center for care, where she was diagnosed with severe anemia. Her anemia worsened during the first week of August, the Ojai Raptor Center said that she was in unstable condition on August 9. Her packed cell volume (PCV) fell below percent, before rising to nine percent.
Jackie died early in the morning on August 10. The necropsy did not reveal a single cause of death, and instead pointed to several factors including severe anemia, blood clots in her wing and one kidney, and liver and lung abnormalities.
Jackie’s resilience inspired millions of people around the world. To honor her memory, FOBBV accepts donations to support its conservation efforts in the area. Supporters can also donate to Ojai Raptor Center’s Bald Eagle Recovery Campaign.
The post Jackie the bald eagle’s final cause of death revealed appeared first on Popular Science.
In the Maricao State Forest on the western end of Puerto Rico, a biologist encountered a flock of parrots in a panic. Raúl Correa of the U.S. Fish and Wildlife Service followed the chaotic squawks and found a young bird in the grips of a red-tailed boa (Boa constrictor).
The snake had trapped a juvenile Puerto Rican parrot (Amazona vittata) on a bamboo stalk. Correa quickly sliced the bamboo, causing the snake to lose its grip and release the bird. USFWS observed the parrot after the incident to ensure it didn’t suffer any lingering injuries. Just a day later, the bird returned to flying with its flock.
Red-tailed boas are considered an invasive species in Puerto Rico. Native to South America, they came to the island in the 1990s through the illegal exotic pet trade. Without anything above it in the food chain, the snakes spread rapidly and have caused widespread damage to native wildlife populations, including the critically endangered Puerto Rican parrot.
https://www.facebook.com/USFWS/posts/pfbid0fRJQr168YUxz4uzLjf4zrPPezcDHaQ7ixXa48RUgWeC9GeaFLuRLyQcNTGs2DY5zlPuerto Rico is also home to a native boa (Chilabothrus inornatus) that is smaller in size. The native Puerto Rican Boa can grow up to 7 feet long. By contrast the invasive red-tailed boa can grow over 10 feet and has introduced viruses to native snake populations on the island, according to a 2023 study.
“Experience has shown that island ecosystems are particularly vulnerable to snake invasions, and unfortunately Puerto Rico has no natural predators that can keep the numbers of these prolific, snakes in check,” said USGS Director Marcia McNutt. “Humans were responsible for introducing this scourge to the island, and are the only hope for mitigating the problem before it is too late for the native species.”
Different places have deployed a variety of tactics to remove invasive snakes species, including Florida that hosts an annual Python Hunt. The contest allows both amateur and professional hunters to kill invasive Burmese pythons (Python bivittatus) for prize money.
The post Young parrot rescued from grips of invasive boa snake appeared first on Popular Science.
Ecuador’s Galapagos Islands are home to an incredible array of wildlife. Amid landscapes of black lava fields, scattered prickly pear cacti, lush highlands, and green mangrove fringes, you’ll spot lumbering land iguanas in striking shades of yellow, orange, and red, comical blue-footed boobies, and some of the pinkest flamingos around. But it turns out that these magnificent creatures aren’t born with their vibrant hues. They actually have to work for them!
To find out why some wildlife changes color according to their diets, and what these various tones and tints mean for survival, Popular Science turned to Jorge Alex Gutierrez Guerrero, an expedition leader on the Galapagos Islands’ Yacht Isabela II. Guerrero says it all comes down to naturally occurring pigments that play a major role in an animal’s immune system. They can even change the color of your skin!
The colorful displays of Galapagos wildlife, including the bright cyan feet of blue-footed boobies and the impressive red throat pouch of magnificent frigatebirds that they inflate during courtship, are a direct result of their diet. Specifically, they result from the digestion of nature’s own punchy dyes known as carotenoids.
“Basically, carotenoids are natural pigments produced by plants, algae, and phytoplankton,” says Gutierrez. These organic chemical compounds play a vital role in nature. They help capture light for photosynthesis, which is how plants use sunlight to make their own food. They act as powerful antioxidants that can protect cells from damage. And they provide the vibrant colors that many animals, birds, and fish need to survive.
For instance, flamingos gradually lose their red pigmentation when their diet lacks carotenoids. According to Gutierrez, this is a perfect example of the “direct relationship between dietary carotenoids and coloration.”
Wildlife in the Galapagos gets carotenoids primarily through their diets, since these are pigments that they can’t produce naturally. The archipelago’s land iguanas eat cactus flowers and leaves to obtain carotenoids, while blue-footed boobies consume fresh fish like sardines and anchovies to acquire them. Pink flamingos get their fill of carotenoids through algae and brine shrimp.
Once the wildlife digests and metabolizes these natural pigments, the colors of carotenoids, which primarily produce shades of red, orange, and yellow, begin to show in everything from skin and shells to feet and feathers. In many cases, the more brilliant the shades, the healthier the creature. While carotenoids don’t naturally create the color blue, the archipelago’s iconic blue-footed boobies get their turquoise feet from a mix of yellow carotenoid pigments and the collagen structure of their skin.
Examples of the power of carotenoids even exist in our own backyards.
The sunny yellow coloring of an American goldfinch is a direct result of its carotenoid-rich diet of summer weeds and sunflowers, while northern cardinals get their brilliant red hue through carotenoid-heavy foods such as honeysuckle, hackberries, and seeds.
Carotenoids aren’t a core nutritional necessity. However, they are an important source of vitamin A, a key component in reproductive health, good vision, and a strong immune system.
While the bulk of birds and animals get carotenoids through their diets, a few rare invertebrates, like spider mites and gall gnats, can create their own carotenoids. They do so through a rare genetic accident, likely caused by a virus or parasite. An ancestor of the spider mite and an ancestor of the gall gnat had close encounters with ancient fungi, causing a horizontal gene transfer. Essentially, horizontal gene transfer is the transmission of DNA between different organisms—and, in this case, species.
Every animal processes these pigments slightly differently. For some animals, carotenoids completely change the color of their features. Others simply absorb carotenoids without changing color at all.
But all animals use carotenoids to fight off disease, such as boosting immune cells to destroy any harmful bacteria. Only healthy wildlife can spare excess carotenoids for bright skin, beaks, or feathers. So the more vibrantly hued birds, reptiles, and fish are, the healthier their immune system. They have enough carotenoids to spare for flashy colors.
For instance, blue-footed boobies with electric, turquoise-blue feet tend to be healthiest. In fact, boobies that go without food for a couple of days can end up with dull-colored feet. When animals get sick, they also lose their hue. First, their bodies divert carotenoids away from exterior features, like skin and feathers, and use them for fighting illness. Second, absorbing nutrients such as carotenoids becomes more difficult. Without carotenoids, an animal’s bright pigments will quickly fade.
Carotenoids also play vital roles in mating rituals. When it comes to blue-footed boobies, “It’s very important for a female to find a male with the brightest blue feet, because she is choosing the best provider” for her offspring, says Gutierrez.
It’s a feature that these marine birds show off frequently in their oh-so-quirky mating dance, which includes an elaborate high-step strut. The bluer the feet, the more attractive males appear to their female counterparts.
What’s more, a famous 2006 scientific study on blue-footed boobies showed that females lay smaller eggs for males with duller feet. Basically, a female will put in less reproductive investment if her male isn’t up to par.
“Carotenoids are prominent all over the world,” says Gutierrez. “But they’re especially visible among wildlife in the Galapagos, because it’s a limited environment where the ecosystems are well-marked.” What Gutierrez means is that the archipelago is so geographically isolated and far from the coast of Ecuador, many species—like marine iguanas—have nowhere else to go. Even within the Galapagos, a large percentage of wildlife stick closely to their specific islands.
Another reason the animals here are so colorful? Because an overall lack of predators has allowed the wildlife to evolve without needing dull or camouflage coats to protect them.
Most of the archipelago’s carotenoids come from the ocean, or in the case of land iguanas and yellow-beaked Darwin’s finches, through cactus nectar and pollen.
Further afield, the iconic pink-orange flesh of Pacific Northwest salmon is a direct result of their carotenoid-rich diet—in their case, chowing down on krill and small shrimp. Roseate spoonbills, found across the mangrove swamps, mudflats, and wetlands of the U.S. Gulf Coast, get their rosy pink sheen from dining on crustaceans, crabs, and crayfish.
As to whether eating carotenoid-rich foods will change a person’s skin color, it’s definitely possible.
The best known example comes from consuming carrots. These vegetables are loaded with a red-orange carotenoid called beta-carotene, which our bodies convert into vitamin A.
But when we consume more beta-carotene than we need, the excess pigment starts circulating in our bloodstream and leads to a yellow or orange glow. “It’s mostly visible in your palms,” says Gutierrez.
Still, he says, don’t worry if you have a penchant for sardines and anchovies—the main diet of blue-footed boobies. Since humans process and metabolize these compounds differently, “you’re not going to turn blue, too.”
In Ask Us Anything, Popular Science answers your most outlandish, mind-burning questions, from the everyday things you’ve always wondered to the bizarre things you never thought to ask. Have something you’ve always wanted to know? Ask us.
The post Why are some animals so colorful? Blame this pigment. appeared first on Popular Science.
During the still night above California’s Big Bear Valley, a meteor recently soared across the sky. Cameras stationed to document the lives of the area’s bald eagles captured an image of the fireball on its journey.
Friends of Big Bear Valley (FOBBV), the non-profit that oversees the 24/7 livestream of the internet’s most famous bald eagles, shared the moment on Facebook with an emotional caption.
https://www.facebook.com/FOBBV/posts/pfbid027at986gqyAS2Vx5NbLuSXS1bMUudE7w2PPT5btRVVV4QQimpPCyWzPunSmoZTCxxl“This morning in the wee hours, a quiet meteor flashed across the night sky. It moved at incredible speed, vanishing in the blink of an eye while the inhabitants of the valley slept,” FOBBV wrote. “This is another reminder of the beautiful land that our eagles and friends inhabit. Nature surrounds us everywhere; in the skies, in the trees, and beyond.”
This year has been an eventful year for Big Bear Valley’s bald eagles. In January, bald eagle mom Jackie laid two eggs that ravens attacked and consumed. She later laid a second clutch of two eggs that both hatched in April. Tens of thousands of fans followed the chicks’ journey as Jackie and her longtime partner Shadow raised the pair. All seemed well on the nest in July when it Jackie disappeared from the cameras’ views.
On July 17, Jackie was found injured on the ground near Dana Point Park, California. Cell phone video from a witness confirmed that she endured a scuffle with two subadult eagles. After being transferred to the Ojai Raptor Center for care, she was diagnosed with severe anemia. Her anemia worsened during the first week of August, and the Ojai Raptor Center reported that she was in unstable condition on August 9. Jackie died early in the morning on August 10. A memorial for Jackie was held this past weekend at Bear Mountain Ski Resort in Big Bear Lake, California.
During Jackie’s absence, another female eagle entered the picture: a 4 year old named Kaydee (originally named KD1). Since her arrival and Jackie’s death, Kaydee and Shadow have been spotted on FOBBV’s cameras sharing peaceful mornings, arranging nest sticks, and singing morning songs.
Shadow and Kaydee were not in the nest when the meteor passed overhead. Without eggs or chicks to care for, most bald eagles sleep in other trees like the nearby Roost Tree. According to FOBBV, the pair spent the morning moving from the Roost Tree to the Lookout Tree before settling to perch on the Twin Pines that afternoon.
It’s not clear what will happen between Shadow and Kaydee, but after an eventful year in Big Bear Valley, a moment of peace under a celestial light show is a welcome pause.
Tune into FOBBV’s livecams for glimpses of the duo.
The post Meteor spotted flying over bald eagle nest appeared first on Popular Science.
Google has started rolling out a new update for the Pixel Buds that brings several new features, and at the same time, the company has slashed $60 off the Pixel Buds Pro 2's price.
Last month, Google started rolling out a feature for Pixel Buds that lets users control their earbuds' settings just by asking Gemini. While you could already ask Gemini to do things like change the volume, the new integration goes much deeper, letting you adjust the EQ, enable or disable ANC, and change other Pixel Buds settings using your voice.
Alongside that, Google has now started rolling out another sizable update for the Pixel Buds Pro, Pixel Buds Pro 2, and Pixel Buds 2a. One of the biggest additions for the Pixel Buds Pro 2 is Dynamic Active Noise Cancellation.
Google previously explained that Dynamic ANC automatically adjusts the noise cancellation based on the seal of the earbuds in your ears. So, if the Pixel Buds move slightly and the seal changes, the earbuds can automatically compensate and adjust the ANC accordingly. That feature is now starting to become available on the Pixel Buds Pro 2.
The Google Pixel Buds Pro 2 are already priced at the lower end of the premium wireless earbuds market, and this Amazon deal shaves another 26% off the sticker price. That brings the Pixel Buds Pro 2 down under $170, which is a stunning price for earbuds that can hang with the best of the best.View Deal
✅ Recommended if: You use a Pixel phone, want strong ANC and Gemini integration, like Google's latest Pixel Buds features, or want premium wireless earbuds for under $200.
❌ Skip this deal if: You don't use Android, want the absolute best battery life, or don't care about Pixel-exclusive features and ecosystem integration.
Google has also added a new tap-to-mute and unmute gesture for calls. So, if you're in an online meeting or taking a phone call, you can simply tap the surface of your Pixel Buds to quickly mute or unmute your microphone.
The Pixel Buds can now automatically pause media playback when you fall asleep as well. This feature requires a paired Pixel Watch to detect when you've fallen asleep, after which your earbuds can pause playback, disable touch gestures, and silence notifications.
Enhanced Live Translate is also starting to roll out. You can now leave your phone in your pocket and start translating using a gesture on the earbuds. Google says the Pixel Buds now work more seamlessly with the Google Translate app to make on-the-go translations easier.
To get these features, make sure you're running the latest version of the Pixel Buds app and look for firmware version release_6.144. You can also manually check for the update by heading to More Settings > Firmware > Check for updates.
And if you've been thinking about buying the Pixel Buds Pro 2, this might be a particularly good time. Thanks to the ongoing Amazon sale, the Pixel Buds Pro 2 are currently $60 off, dropping from their usual $230 price to just $170.
So, not only are you getting them for considerably less right now, but Google has also made the Pixel Buds Pro 2 noticeably more capable with the latest software update.
In March 2023, Southern California experienced heavy storms after almost 20 years of drought. Sixteen of these came from long, narrow regions of concentrated water vapor moving through the air, known as atmospheric rivers. During droughts, groundwater supplies up to 60% of the total water to the Greater Los Angeles area, so researchers think that stormwater from the 2023 events could have recharged groundwater reserves for future use. However, scientists lack adequate tools to assess how much groundwater is in the subsurface.
To overcome this challenge, researchers from California and Texas developed a new method to study deep groundwater. California gets a large number of earthquakes, so it has over 450 stations around the state to monitor the associated vibrations, referred to as seismic waves. To study how much the 2023 storm recharged the groundwater in the Greater Los Angeles area, the team used a tool called seismic-DI, which employs these seismic waves to estimate how much groundwater is stored at different depths.
Seismic-DI works by measuring how fast seismic waves move through the Earth, known as their seismic velocity. The researchers explained that the Greater Los Angeles area is a very crowded city, so it produces an abundance of seismic waves. They measured changes in the seismic velocities of these underground waves to see where the groundwater is full of water, or saturated, versus partially full, or unsaturated. They used 20 years of these data to produce graphs that record changes in groundwater storage at different depths, known as hydrographs.
To validate the accuracy of seismic-DI, the researchers also compared their seismic hydrographs with groundwater thickness data from a NASA mission known as the Gravity Recovery and Climate Experiment, or GRACE. GRACE consists of 2 satellites that measure changes in Earth’s gravity, which reflect surface water and groundwater storage. Both their seismic hydrographs and the GRACE groundwater data demonstrated that the Greater Los Angeles region experienced an increase in groundwater storage from stormwater in the winter, and a reduction in groundwater storage during the dry summer.
The team’s hydrographs showed that the 2023 storms saturated the Greater Los Angeles area groundwater down to 35 meters (114 feet), but it was abnormally dry at 200 meters (656 feet), and at a severe drought at 450 meters (1,476 feet). The GRACE data similarly demonstrated that the subsurface is in severe drought. Combined, these data indicated the 2023 storms helped the Greater Los Angeles area recover up to 90% of its groundwater at depths of 50 meters (164 feet) since the 2006-2022 drought. However, it recovered only about 40% at 75 meters (246 feet) and 20% to 30% at 100 meters (328 feet).
They concluded that the 2023 atmospheric river events recharged only shallow groundwater reserves in the Los Angeles area. As a result, they suggested future researchers consider deep groundwater reserves for a more complete assessment of total regional water deficits. While this study demonstrated that seismic-DI can successfully reveal spatial changes in groundwater and drought at depth, the team acknowledged that contributing factors like the amount, rate, and spatial variability of groundwater reserves remain targets of future work.
The post Using seismic stations to track groundwater resources appeared first on Sciworthy.
More than 90,000 tons of radioactive waste are stored on-site at nuclear power plants awaiting permanent disposal. Nuclear waste releases unstable forms of uranium and other elements, called radionuclides. Long-term exposure to radionuclides can cause cancer, so environmental safety regulations require that nuclear waste be made inaccessible for at least 1 million years. Thus, researchers are evaluating possible ways to store this waste permanently.
One proposal is to store nuclear waste thousands of feet below ground in rock formations called deep geological repositories, or DGRs, to seal in radionuclides. Scientists can’t see into the future, so instead they look to the past to determine how well DRGs could work. A team of researchers from Canada recently analyzed uranium deposits that have existed for billions of years as an analog for how nuclear waste behaves deep underground.
Past researchers found that uranium deposits in ideal DGR conditions, with their protective casings intact, will stay contained for more than a billion years. However, these conditions require a stable geological environment. This team instead focused on uranium deposits in non-ideal conditions. They studied the Canadian Kiggavik uranium deposits, which occur in cracked bedrock approximately 500 meters (1,600 feet) below the surface. The team claimed these conditions are similar to DRGs with broken protective casings.
The team knew from previous work that most of the uranium minerals in the Kiggavik deposits are more than 274 million years old, but about 10% are less than 1 million years old. They found that these younger uranium minerals occurred alongside clay minerals surrounding the older uranium minerals and within open fractures. The researchers interpreted the older uranium as the source material of the younger uranium because of their proximity. They concluded that water must have infiltrated the deposits and interacted with older minerals, transporting uranium and forming new, younger minerals.
To determine the source of water infiltration, the researchers compared the chemistry of clay minerals formed alongside the younger uranium with modern snow in the Kiggavik region. They looked at the number of neutrons, or isotopes, in hydrogen atoms within the clay minerals, and found heavy values matching those of fresh water. These values indicated that snow or glacial meltwater was the source, rather than underlying bedrock or seawater.
To determine when the water infiltrated over the last million years, the researchers used uranium-thorium dating to find when the radionuclides were mobilized. This dating method shows when uranium was removed from the original minerals by measuring how much its concentration was reduced by water infiltration. They found that the dates of these radionuclide mobilizations clustered into 5 separate water-infiltration events that occurred from 36 to 470 thousand years ago.
Comparing these dates with existing climate records, the researchers found that the water infiltration events overlapped with periods when glaciers covered the ground surface. Normally, water can’t travel thousands of feet underground. But, like a hydraulic press, a glacier pushes water at its base downward. If the water encountered cracks in the ground, the pressure could inject it to the depth of the uranium deposit.
Next, the researchers wanted to measure how quickly radionuclides left the deposit. They measured the maximum distance between younger and older uranium minerals and used the age of the most recent water-infiltration event to estimate the fastest speed at which the radionuclides could have moved. They determined this maximum speed to be 0.0014 millimeters (0.000055 inches) per year. At that rate, they calculated it would take 360 million years for uranium radionuclides to travel 500 meters from a DGR at the same depth as the Kiggavik uranium deposits to the surface. This timescale far exceeds the necessary 1 million years for nuclear waste containment.
The team concluded that if glaciers were to return to Kiggavik, the uranium deposits wouldn’t experience substantial radionuclide movement, even in contact with glacial meltwater. Similarly, if a DGR has broken protective casings, radionuclides would be moving too slowly to reach the surface even if water leaked into it. They suggested their findings reduce constraints on viable DGR sites and could help ensure the long-term secure storage of nuclear waste.
The post Is nuclear waste safe underground? appeared first on Sciworthy.
Waterfalls play an essential role in river development and landscape evolution. Researchers are particularly interested in how abrupt changes in the steepness of a river channel, also called knickpoints, develop. Knickpoints vary in size and can be as small as your index finger or as large as Niagara Falls. Researchers from Virginia hypothesized that waterfalls, a type of knickpoint, can influence erosion when a river channel is cut into solid rock, called bedrock.
The researchers wondered whether fractures and other pre-existing weaknesses can influence how water removes rock slabs from a river channel, via an erosional process called plucking. Fractures can form in many different orientations, but the researchers focused on 3. Imagine a flat tabletop that represents a riverbed. Fractures that are parallel to the flat tabletop are called horizontal fractures. If you tip the table so the low end points downstream, that’s the direction of downstream-dipping fractures. If you tip the table so the low end points upstream, that’s the direction of upstream-dipping fractures.
First, the researchers tested how fracture orientation changed erosion before an established knickpoint. They used a man-made channel, called a flume, to simulate a natural river system. To set up the experiment, they glued layers of small tiles about the size of an adult’s thumbnail to a plastic frame and put it in the flume. Then, they placed a layer of unglued tiles upstream of the knickpoint.
To begin the experiment, the researchers incrementally increased the amount of water flowing through the flume every 5 minutes until they reached a maximum flow or all the loose tiles were “eroded.” They considered a tile to be “eroded” once it was transported over the knickpoint and downstream. The researchers measured the water depth at a fixed point upstream of the knickpoint, the number of tiles eroded through plucking, and the volume of water. They repeated this 8 times for each fracture orientation.
The team found differences in the amount and timing of erosion between the 3 orientations. In particular, they saw that erosion began at lower water speeds for horizontal beds than for tilted beds. Based on the observed erosion rates, they concluded that horizontal beds are the most susceptible to erosion, while upstream-dipping beds are the most resistant, and downstream-dipping beds fall between the 2.
The researchers then tested how a knickpoint would develop and influence water flow if all of the tiles were unglued and free to move. They individually stacked almost 5,000 unglued tiles across the channel. Before starting the experiment, they filled the flume slowly with water to submerge all of the tiles without moving them. Then, they increased the water’s speed to start erosion. Instead of collecting measurements as they did in the first experiment, the researchers filmed this experiment and observed how the knickpoint shape changed and how plucking occurred.
The researchers observed that the plucked tiles in this experiment formed piles downstream of the knickpoint in a process known as armoring. This armor of tiles, which represents loose rocks near a waterfall in a natural setting, prevents erosion of the underlying river bed. Only when the water transports the armor downstream can it erode the bedrock and develop a knickpoint.
Unlike the first experiment, researchers found no differences in erosion between fracture orientations in this experiment, but did observe differences in armoring. They found that upstream-dipping beds had the least armoring because water quickly transported piles of tiles near the waterfall downstream. Downstream-dipping beds had the most armoring, and their eroded tiles took longer to move downstream.
The team concluded that waterfalls will erode at different rates based on their fracture orientation and armoring processes. The orientation of bedrock fractures also impacts the shape of the waterfall and the river channel around it. So the next time you see a large waterfall, consider that it may have started as a small fracture the size of your thumbnail.
The post Bedrock fractures shape waterfalls appeared first on Sciworthy.
Login