Microsoft’s carbon removal plans aren’t dead after all | TechCrunch
Microsoft is purchasing 650,000 metric tons of carbon removal credits from startup BioCirc, the company said today.
As carbon removal deals go, it’s not a big buy. But this one is notable because last month, two reports said the tech giant was pausing its carbon removal deals. BioCirc confirmed for TechCrunch that the purchase agreement was signed in May, weeks after Microsoft reportedly paused new deals.
For the carbon removal industry — and the startups that depend on it — there’s a big difference between a pause and a recalibration. Microsoft is reportedly responsible for more than 90% of the carbon removal credit market, meaning its purchasing decisions alone can determine whether young companies in the space survive.
Microsoft repeatedly denied that it had paused its carbon removal purchases. “Our carbon removal program has not ended,” Melanie Nakagawa, chief sustainability officer at Microsoft, told TechCrunch in a statement. “At times we may adjust the pace or volume of our carbon removal procurement as we continue to refine our approach toward sustainability goals.”
The new deal generates carbon removal credits from five BioCirc biogas projects. The biogas plants take biomass waste — frequently from agriculture — and use industrial bioreactors to turn it into methane and carbon dioxide. BioCirc captures the carbon dioxide and stores it in an underground reservoir offshore. The methane is then burned in a power plant.
Microsoft’s sustainability goals have been strained by the company’s push into AI. To power its data centers in Texas, Microsoft last month said it was working with Chevron and Engine No. 1 to build a natural gas power plant in the state that could eventually generate 5 gigawatts of electricity. Emissions from that project alone promise to dwarf the deal with BioCirc.
Internally, Microsoft employees have also been debating whether to abandon the company’s goal of matching zero emissions electricity with its energy use on an hourly basis. Today, the company matches on an annual basis. That approach gives the company more flexibility to, say, use more natural gas to power its data centers at night, but it also makes the company’s clean energy claims harder to verify.
If Microsoft continues to pursue fossil fuel power plants, it’ll need to ramp up its carbon removal purchases to meet its 2030 target of becoming a carbon negative company (one that removes more greenhouse gases from the atmosphere than it generates).
Last year, Microsoft signed several deals worth millions of tons of carbon removal credits. The program’s reported pause set off alarm bells throughout the carbon removal industry, which is still in its infancy.
The new deal suggests that Microsoft is, in fact, recalibrating its carbon removal program — not abandoning it. Whether that remains true as AI drives its energy consumption higher is something the industry will be watching.
Microsoft is purchasing 650,000 metric tons of carbon removal credits from startup BioCirc, the company said today.
As carbon removal deals go, it’s not a big buy. But this one is notable because last month, two reports said the tech giant was pausing its carbon removal deals. BioCirc confirmed for TechCrunch that the purchase agreement was signed in May, weeks after Microsoft reportedly paused new deals.
For the carbon removal industry — and the startups that depend on it — there’s a big difference between a pause and a recalibration. Microsoft is reportedly responsible for more than 90% of the carbon removal credit market, meaning its purchasing decisions alone can determine whether young companies in the space survive.
Microsoft repeatedly denied that it had paused its carbon removal purchases. “Our carbon removal program has not ended,” Melanie Nakagawa, chief sustainability officer at Microsoft, told TechCrunch in a statement. “At times we may adjust the pace or volume of our carbon removal procurement as we continue to refine our approach toward sustainability goals.”
The new deal generates carbon removal credits from five BioCirc biogas projects. The biogas plants take biomass waste — frequently from agriculture — and use industrial bioreactors to turn it into methane and carbon dioxide. BioCirc captures the carbon dioxide and stores it in an underground reservoir offshore. The methane is then burned in a power plant.
Microsoft’s sustainability goals have been strained by the company’s push into AI. To power its data centers in Texas, Microsoft last month said it was working with Chevron and Engine No. 1 to build a natural gas power plant in the state that could eventually generate 5 gigawatts of electricity. Emissions from that project alone promise to dwarf the deal with BioCirc.
Internally, Microsoft employees have also been debating whether to abandon the company’s goal of matching zero emissions electricity with its energy use on an hourly basis. Today, the company matches on an annual basis. That approach gives the company more flexibility to, say, use more natural gas to power its data centers at night, but it also makes the company’s clean energy claims harder to verify.
If Microsoft continues to pursue fossil fuel power plants, it’ll need to ramp up its carbon removal purchases to meet its 2030 target of becoming a carbon negative company (one that removes more greenhouse gases from the atmosphere than it generates).
Last year, Microsoft signed several deals worth millions of tons of carbon removal credits. The program’s reported pause set off alarm bells throughout the carbon removal industry, which is still in its infancy.
The new deal suggests that Microsoft is, in fact, recalibrating its carbon removal program — not abandoning it. Whether that remains true as AI drives its energy consumption higher is something the industry will be watching.
When you purchase through links in our articles, we may earn a small commission. This doesn’t affect our editorial independence.
#Microsofts #carbon #removal #plans #arent #dead #TechCrunchMicrosoft,biogas,Exclusive,carbon credits,carbon removal![xAI fired an engineer who raised alarms about Grok safety, new lawsuit claims | TechCrunch
A former engineer at Elon Musk’s xAI has filed suit against the company and its parent SpaceX claiming he was fired for raising concerns about AI safety.
Devin Kim, who left xAI in September 2025, filed the suit in a California state court on Tuesday. The complaint comes days before SpaceX is set to join the public markets in what’s shaping up to be the largest IPO in history.
According to the lawsuit, which TechCrunch has viewed, Kim became a prominent voice for AI safety while working on Grok, xAI’s AI chatbot. He allegedly complained repeatedly about xAI’s failure to prioritize safety in Grok’s development, a product that has since come under fire for a range of safety and behavioral issues. In particular, Kim was concerned with the possibility that Grok could foment discrimination and help spread information about weapons of mass destruction.
“Grok, of course, proved Mr. Kim right by engaging in spectacular displays of online hatred and vitriol, with the model likening itself to Hitler (‘MechaHitler’),” the lawsuit reads. “Following the Hitler debacle, Mr. Kim worked to re-evaluate Grok’s political bias and discriminatory tendencies.”
September was my last month at xAI! I joined as one of the first members of the post-training team in 2024 and eventually led research tooling, where we built some of the world’s best systems to accelerate Grok’s development.On my first day, I was at the whiteboard with @ibab…— Devin Kim (@devindkim) October 3, 2025
A few months after Kim departed xAI, Grok made headlines again when the chatbot was used to flood X — Musk’s social media platform that also falls under the xAI umbrella — with nonconsensual sexual imagery.
The lawsuit also positions Kim as a whistleblower who was concerned about xAI’s alleged disregard for AI safety as “unlawful” in areas such as internet regulation, consumer protection and unfair business practices, and arms and explosives regulation, among others.
xAI and SpaceX did not immediately respond to requests for comment.
Kim’s focus on AI safety predates his time at xAI. While working at Scale AI, Kim worked on early safety AI initiatives, like leading a project that produced training data for AI to train systems to detect harmful content and comply with governance policies. Last week, the nonprofit Center for AI Safety, which focuses on AI risks, named Kim as its president.
Interestingly, the lawsuit doesn’t implicate Musk himself as a reason for a lack of safety. Rather, Kim’s lawyers describe Musk as having directed xAI to follow the law and implement appropriate safety and testing processes. Instead the claim targets Kim’s supervisor, xAI co-founder Jimmy Ba — who left the company earlier this year — saying that Ba ignored Musk’s directives and retaliated against Kim for pushing for safeguards, in an effort to “silence his repeated complaints about AI safety and biases.”
The lawsuit portrays Ba as someone who vehemently opposed AI safety measures, allegedly telling Kim at one point “AI will kill us all anyway,” and who was instead driven by a mission to make xAI the first to reach superintelligence.
“In one instance in or around August 2025, Mr. Ba attempted to thwart EU safety regulations during the release of Grok Code 1, misrepresenting aspects of the model in order to avoid legally required testing,” the complaint says. “Mr. Ba indicated that he would rather release an unsafe model than a poor-performing one. Mr. Musk ultimately had to intervene.”
According to the lawsuit, Kim intended to give a presentation of his findings the week of September 15, 2025, but Ba called him into a meeting and told him they should “go [their] separate ways” without providing a satisfactory reason.
TechCrunch has reached out to Ba for comment.
Kim is seeking compensatory and punitive damages, as well as a declaratory judgment that xAI and SpaceX’s conduct was unlawful.
When you purchase through links in our articles, we may earn a small commission. This doesn’t affect our editorial independence.#xAI #fired #engineer #raised #alarms #Grok #safety #lawsuit #claims #TechCrunchai safety,devin kim,Grok,SpaceX,xAI](https://i3.wp.com/techcrunch.com/wp-content/uploads/2026/03/grok-getty.jpg?resize=1200%2C800&ssl=1 "xAI fired an engineer who raised alarms about Grok safety, new lawsuit claims | TechCrunch
A former engineer at Elon Musk’s xAI has filed suit against the company and its parent SpaceX claiming he was fired for raising concerns about AI safety.
Devin Kim, who left xAI in September 2025, filed the suit in a California state court on Tuesday. The complaint comes days before SpaceX is set to join the public markets in what’s shaping up to be the largest IPO in history.
According to the lawsuit, which TechCrunch has viewed, Kim became a prominent voice for AI safety while working on Grok, xAI’s AI chatbot. He allegedly complained repeatedly about xAI’s failure to prioritize safety in Grok’s development, a product that has since come under fire for a range of safety and behavioral issues. In particular, Kim was concerned with the possibility that Grok could foment discrimination and help spread information about weapons of mass destruction.
“Grok, of course, proved Mr. Kim right by engaging in spectacular displays of online hatred and vitriol, with the model likening itself to Hitler (‘MechaHitler’),” the lawsuit reads. “Following the Hitler debacle, Mr. Kim worked to re-evaluate Grok’s political bias and discriminatory tendencies.”
September was my last month at xAI! I joined as one of the first members of the post-training team in 2024 and eventually led research tooling, where we built some of the world’s best systems to accelerate Grok’s development.On my first day, I was at the whiteboard with @ibab…— Devin Kim (@devindkim) October 3, 2025
A few months after Kim departed xAI, Grok made headlines again when the chatbot was used to flood X — Musk’s social media platform that also falls under the xAI umbrella — with nonconsensual sexual imagery.
The lawsuit also positions Kim as a whistleblower who was concerned about xAI’s alleged disregard for AI safety as “unlawful” in areas such as internet regulation, consumer protection and unfair business practices, and arms and explosives regulation, among others.
xAI and SpaceX did not immediately respond to requests for comment.
Kim’s focus on AI safety predates his time at xAI. While working at Scale AI, Kim worked on early safety AI initiatives, like leading a project that produced training data for AI to train systems to detect harmful content and comply with governance policies. Last week, the nonprofit Center for AI Safety, which focuses on AI risks, named Kim as its president.
Interestingly, the lawsuit doesn’t implicate Musk himself as a reason for a lack of safety. Rather, Kim’s lawyers describe Musk as having directed xAI to follow the law and implement appropriate safety and testing processes. Instead the claim targets Kim’s supervisor, xAI co-founder Jimmy Ba — who left the company earlier this year — saying that Ba ignored Musk’s directives and retaliated against Kim for pushing for safeguards, in an effort to “silence his repeated complaints about AI safety and biases.”
The lawsuit portrays Ba as someone who vehemently opposed AI safety measures, allegedly telling Kim at one point “AI will kill us all anyway,” and who was instead driven by a mission to make xAI the first to reach superintelligence.
“In one instance in or around August 2025, Mr. Ba attempted to thwart EU safety regulations during the release of Grok Code 1, misrepresenting aspects of the model in order to avoid legally required testing,” the complaint says. “Mr. Ba indicated that he would rather release an unsafe model than a poor-performing one. Mr. Musk ultimately had to intervene.”
According to the lawsuit, Kim intended to give a presentation of his findings the week of September 15, 2025, but Ba called him into a meeting and told him they should “go [their] separate ways” without providing a satisfactory reason.
TechCrunch has reached out to Ba for comment.
Kim is seeking compensatory and punitive damages, as well as a declaratory judgment that xAI and SpaceX’s conduct was unlawful.
When you purchase through links in our articles, we may earn a small commission. This doesn’t affect our editorial independence.#xAI #fired #engineer #raised #alarms #Grok #safety #lawsuit #claims #TechCrunchai safety,devin kim,Grok,SpaceX,xAI")
![Scientists Found a Continent-Sized Geological Structure Hiding Beneath Antarctica
The East Antarctic Ice Sheet is almost unfathomably huge. Covering about 75% of the entire frigid continent (nearly everything on its side of the Transantarctic Mountains), the sheet covers about 3.9 million square miles (10.2 million square kilometers) and extends down 1.4 miles (2.2 km), on average, before coming into contact with Earth’s surface. At its deepest, the ice plunges down over 3 miles (4.9 km). For decades, scientists assumed that this literally continent-sized block of ice rested on an expansive and stable chunk of Earth’s crust known as a craton. A team of researchers has now complicated that picture—mapping a vast, interconnected geological structure that fans out from a troubling “tectonic deformation.” Beneath this ice sheet, thinner and more geologically recent slices of crusty lithosphere fan out into hidden valleys called “pull-apart basins.” These basins—30 elongated wedge-shaped valleys in total—constitute an entirely new, continental-scale geological region underneath Antarctica, in fact, one which the researchers have named the East Antarctic Fan-Shaped Basin Province (EAFBP). But it’s how they likely formed that has now caught researchers’ attention.
To put it bluntly, it turns out that about 90% of the planet’s fresh water ice may not be on solid ground. Geologist John Goodge called the team’s findings “provocative” in an independent commentary on the new study, published Thursday in the journal Nature Geoscience.
“East Antarctica is typically considered from seismic tomography and geodetics to be ancient and generally stable,” according to Goodge, who studies continental tectonics with the nonprofit Planetary Science Institute. “[But] something else is going on at depth.” Continental divides Goodge speculates that this seemingly “coherent pull-apart system,” as presented in the new study, might help explain a variety of mysterious heat and water flows beneath this ice sheet’s surface, like that enormous subglacial lake identified in 2016 or some of the hundreds more like it.
The study’s authors, led by geophysicist Egidio Armadillo at the University of Genoa in Italy, agreed: “Because these basins underlie about half of the East Antarctic Ice Sheet, they are likely to heavily influence both ice-flow and landscape evolution,” the researchers wrote in their study, also published Thursday in Nature Geoscience. Armadillo’s team, coordinating across Europe and the U.K., developed their new understanding of Antarctica’s hidden bedrock via an exhaustive set of sensory data. Gravitational and magnetic anomalies were mapped via low-altitude airborne surveys. Ground surface features were mapped with seismic tools, using sound waves that vibrate through the ice and ping back information about subglacial landscapes in 3D. The grey, magenta, and cyan lines represent the apparent new fault lines discovered. Credit: Nature Geoscience All of this data—the fruits of “multi-national efforts to image within and below the ice sheet,” as Goodge put it—had already revealed that regions of the continent were “undergoing more rapid movement and ice-mass loss than previously recognized.” Armadillo’s team merely helped to explain why.
The mechanism Armadillo and his colleagues proposed for the formation of these fan-shaped basins is called “distributed rotational extension.” It involves points called Euler poles around which tectonic plates pivot or rotate rather than smash into each other or pull apart. The result is a bit like decks of cards being spread out on a table, thinning out the stack of Earth’s crust as it moves. An icy situation Goodge took pains to spell out the basins’ implications for melting Antarctic ice due to climate change and the risk of rising global sea levels.
The mere existence of these basins, he wrote, “could introduce widespread, systemic instability to the East Antarctic Ice Sheet” via thinner layers of Earth’s crust and more heat flow from below. On top of that, a series of fault-line “troughs” documented between the basins appear “tailor-made to promote outward flow of ice streams from the interior” into the world’s oceans, he said. That said, the team’s findings are unlikely to end this debate. As Goodge noted, Antarctica is “the last continental frontier of scientific exploration.” It’s still a very mysterious place, one that’s challenging to study given its inhospitable temperatures and extreme geography. Its “cryptic subglacial geology” might stay that way for a while. #Scientists #ContinentSized #Geological #Structure #Hiding #Beneath #AntarcticaAntarctica,Geology,mapping,Plate tectonics](https://gizmodo.com/app/uploads/2026/06/East-Antarctic-Fan-shaped-Basin-Province.jpeg "Scientists Found a Continent-Sized Geological Structure Hiding Beneath Antarctica
The East Antarctic Ice Sheet is almost unfathomably huge. Covering about 75% of the entire frigid continent (nearly everything on its side of the Transantarctic Mountains), the sheet covers about 3.9 million square miles (10.2 million square kilometers) and extends down 1.4 miles (2.2 km), on average, before coming into contact with Earth’s surface. At its deepest, the ice plunges down over 3 miles (4.9 km). For decades, scientists assumed that this literally continent-sized block of ice rested on an expansive and stable chunk of Earth’s crust known as a craton. A team of researchers has now complicated that picture—mapping a vast, interconnected geological structure that fans out from a troubling “tectonic deformation.” Beneath this ice sheet, thinner and more geologically recent slices of crusty lithosphere fan out into hidden valleys called “pull-apart basins.” These basins—30 elongated wedge-shaped valleys in total—constitute an entirely new, continental-scale geological region underneath Antarctica, in fact, one which the researchers have named the East Antarctic Fan-Shaped Basin Province (EAFBP). But it’s how they likely formed that has now caught researchers’ attention.
To put it bluntly, it turns out that about 90% of the planet’s fresh water ice may not be on solid ground. Geologist John Goodge called the team’s findings “provocative” in an independent commentary on the new study, published Thursday in the journal Nature Geoscience.
“East Antarctica is typically considered from seismic tomography and geodetics to be ancient and generally stable,” according to Goodge, who studies continental tectonics with the nonprofit Planetary Science Institute. “[But] something else is going on at depth.” Continental divides Goodge speculates that this seemingly “coherent pull-apart system,” as presented in the new study, might help explain a variety of mysterious heat and water flows beneath this ice sheet’s surface, like that enormous subglacial lake identified in 2016 or some of the hundreds more like it.
The study’s authors, led by geophysicist Egidio Armadillo at the University of Genoa in Italy, agreed: “Because these basins underlie about half of the East Antarctic Ice Sheet, they are likely to heavily influence both ice-flow and landscape evolution,” the researchers wrote in their study, also published Thursday in Nature Geoscience. Armadillo’s team, coordinating across Europe and the U.K., developed their new understanding of Antarctica’s hidden bedrock via an exhaustive set of sensory data. Gravitational and magnetic anomalies were mapped via low-altitude airborne surveys. Ground surface features were mapped with seismic tools, using sound waves that vibrate through the ice and ping back information about subglacial landscapes in 3D. The grey, magenta, and cyan lines represent the apparent new fault lines discovered. Credit: Nature Geoscience All of this data—the fruits of “multi-national efforts to image within and below the ice sheet,” as Goodge put it—had already revealed that regions of the continent were “undergoing more rapid movement and ice-mass loss than previously recognized.” Armadillo’s team merely helped to explain why.
The mechanism Armadillo and his colleagues proposed for the formation of these fan-shaped basins is called “distributed rotational extension.” It involves points called Euler poles around which tectonic plates pivot or rotate rather than smash into each other or pull apart. The result is a bit like decks of cards being spread out on a table, thinning out the stack of Earth’s crust as it moves. An icy situation Goodge took pains to spell out the basins’ implications for melting Antarctic ice due to climate change and the risk of rising global sea levels.
The mere existence of these basins, he wrote, “could introduce widespread, systemic instability to the East Antarctic Ice Sheet” via thinner layers of Earth’s crust and more heat flow from below. On top of that, a series of fault-line “troughs” documented between the basins appear “tailor-made to promote outward flow of ice streams from the interior” into the world’s oceans, he said. That said, the team’s findings are unlikely to end this debate. As Goodge noted, Antarctica is “the last continental frontier of scientific exploration.” It’s still a very mysterious place, one that’s challenging to study given its inhospitable temperatures and extreme geography. Its “cryptic subglacial geology” might stay that way for a while. #Scientists #ContinentSized #Geological #Structure #Hiding #Beneath #AntarcticaAntarctica,Geology,mapping,Plate tectonics")
![Scientists Found a Continent-Sized Geological Structure Hiding Beneath Antarctica
The East Antarctic Ice Sheet is almost unfathomably huge. Covering about 75% of the entire frigid continent (nearly everything on its side of the Transantarctic Mountains), the sheet covers about 3.9 million square miles (10.2 million square kilometers) and extends down 1.4 miles (2.2 km), on average, before coming into contact with Earth’s surface. At its deepest, the ice plunges down over 3 miles (4.9 km). For decades, scientists assumed that this literally continent-sized block of ice rested on an expansive and stable chunk of Earth’s crust known as a craton. A team of researchers has now complicated that picture—mapping a vast, interconnected geological structure that fans out from a troubling “tectonic deformation.” Beneath this ice sheet, thinner and more geologically recent slices of crusty lithosphere fan out into hidden valleys called “pull-apart basins.” These basins—30 elongated wedge-shaped valleys in total—constitute an entirely new, continental-scale geological region underneath Antarctica, in fact, one which the researchers have named the East Antarctic Fan-Shaped Basin Province (EAFBP). But it’s how they likely formed that has now caught researchers’ attention.
To put it bluntly, it turns out that about 90% of the planet’s fresh water ice may not be on solid ground. Geologist John Goodge called the team’s findings “provocative” in an independent commentary on the new study, published Thursday in the journal Nature Geoscience.
“East Antarctica is typically considered from seismic tomography and geodetics to be ancient and generally stable,” according to Goodge, who studies continental tectonics with the nonprofit Planetary Science Institute. “[But] something else is going on at depth.” Continental divides Goodge speculates that this seemingly “coherent pull-apart system,” as presented in the new study, might help explain a variety of mysterious heat and water flows beneath this ice sheet’s surface, like that enormous subglacial lake identified in 2016 or some of the hundreds more like it.
The study’s authors, led by geophysicist Egidio Armadillo at the University of Genoa in Italy, agreed: “Because these basins underlie about half of the East Antarctic Ice Sheet, they are likely to heavily influence both ice-flow and landscape evolution,” the researchers wrote in their study, also published Thursday in Nature Geoscience. Armadillo’s team, coordinating across Europe and the U.K., developed their new understanding of Antarctica’s hidden bedrock via an exhaustive set of sensory data. Gravitational and magnetic anomalies were mapped via low-altitude airborne surveys. Ground surface features were mapped with seismic tools, using sound waves that vibrate through the ice and ping back information about subglacial landscapes in 3D. The grey, magenta, and cyan lines represent the apparent new fault lines discovered. Credit: Nature Geoscience All of this data—the fruits of “multi-national efforts to image within and below the ice sheet,” as Goodge put it—had already revealed that regions of the continent were “undergoing more rapid movement and ice-mass loss than previously recognized.” Armadillo’s team merely helped to explain why.
The mechanism Armadillo and his colleagues proposed for the formation of these fan-shaped basins is called “distributed rotational extension.” It involves points called Euler poles around which tectonic plates pivot or rotate rather than smash into each other or pull apart. The result is a bit like decks of cards being spread out on a table, thinning out the stack of Earth’s crust as it moves. An icy situation Goodge took pains to spell out the basins’ implications for melting Antarctic ice due to climate change and the risk of rising global sea levels.
The mere existence of these basins, he wrote, “could introduce widespread, systemic instability to the East Antarctic Ice Sheet” via thinner layers of Earth’s crust and more heat flow from below. On top of that, a series of fault-line “troughs” documented between the basins appear “tailor-made to promote outward flow of ice streams from the interior” into the world’s oceans, he said. That said, the team’s findings are unlikely to end this debate. As Goodge noted, Antarctica is “the last continental frontier of scientific exploration.” It’s still a very mysterious place, one that’s challenging to study given its inhospitable temperatures and extreme geography. Its “cryptic subglacial geology” might stay that way for a while. #Scientists #ContinentSized #Geological #Structure #Hiding #Beneath #AntarcticaAntarctica,Geology,mapping,Plate tectonics](https://i0.wp.com/gizmodo.com/app/uploads/2026/06/East-Antarctic-Fan-shaped-Basin-Province.jpeg?ssl=1 "Scientists Found a Continent-Sized Geological Structure Hiding Beneath Antarctica
The East Antarctic Ice Sheet is almost unfathomably huge. Covering about 75% of the entire frigid continent (nearly everything on its side of the Transantarctic Mountains), the sheet covers about 3.9 million square miles (10.2 million square kilometers) and extends down 1.4 miles (2.2 km), on average, before coming into contact with Earth’s surface. At its deepest, the ice plunges down over 3 miles (4.9 km). For decades, scientists assumed that this literally continent-sized block of ice rested on an expansive and stable chunk of Earth’s crust known as a craton. A team of researchers has now complicated that picture—mapping a vast, interconnected geological structure that fans out from a troubling “tectonic deformation.” Beneath this ice sheet, thinner and more geologically recent slices of crusty lithosphere fan out into hidden valleys called “pull-apart basins.” These basins—30 elongated wedge-shaped valleys in total—constitute an entirely new, continental-scale geological region underneath Antarctica, in fact, one which the researchers have named the East Antarctic Fan-Shaped Basin Province (EAFBP). But it’s how they likely formed that has now caught researchers’ attention.
To put it bluntly, it turns out that about 90% of the planet’s fresh water ice may not be on solid ground. Geologist John Goodge called the team’s findings “provocative” in an independent commentary on the new study, published Thursday in the journal Nature Geoscience.
“East Antarctica is typically considered from seismic tomography and geodetics to be ancient and generally stable,” according to Goodge, who studies continental tectonics with the nonprofit Planetary Science Institute. “[But] something else is going on at depth.” Continental divides Goodge speculates that this seemingly “coherent pull-apart system,” as presented in the new study, might help explain a variety of mysterious heat and water flows beneath this ice sheet’s surface, like that enormous subglacial lake identified in 2016 or some of the hundreds more like it.
The study’s authors, led by geophysicist Egidio Armadillo at the University of Genoa in Italy, agreed: “Because these basins underlie about half of the East Antarctic Ice Sheet, they are likely to heavily influence both ice-flow and landscape evolution,” the researchers wrote in their study, also published Thursday in Nature Geoscience. Armadillo’s team, coordinating across Europe and the U.K., developed their new understanding of Antarctica’s hidden bedrock via an exhaustive set of sensory data. Gravitational and magnetic anomalies were mapped via low-altitude airborne surveys. Ground surface features were mapped with seismic tools, using sound waves that vibrate through the ice and ping back information about subglacial landscapes in 3D. The grey, magenta, and cyan lines represent the apparent new fault lines discovered. Credit: Nature Geoscience All of this data—the fruits of “multi-national efforts to image within and below the ice sheet,” as Goodge put it—had already revealed that regions of the continent were “undergoing more rapid movement and ice-mass loss than previously recognized.” Armadillo’s team merely helped to explain why.
The mechanism Armadillo and his colleagues proposed for the formation of these fan-shaped basins is called “distributed rotational extension.” It involves points called Euler poles around which tectonic plates pivot or rotate rather than smash into each other or pull apart. The result is a bit like decks of cards being spread out on a table, thinning out the stack of Earth’s crust as it moves. An icy situation Goodge took pains to spell out the basins’ implications for melting Antarctic ice due to climate change and the risk of rising global sea levels.
The mere existence of these basins, he wrote, “could introduce widespread, systemic instability to the East Antarctic Ice Sheet” via thinner layers of Earth’s crust and more heat flow from below. On top of that, a series of fault-line “troughs” documented between the basins appear “tailor-made to promote outward flow of ice streams from the interior” into the world’s oceans, he said. That said, the team’s findings are unlikely to end this debate. As Goodge noted, Antarctica is “the last continental frontier of scientific exploration.” It’s still a very mysterious place, one that’s challenging to study given its inhospitable temperatures and extreme geography. Its “cryptic subglacial geology” might stay that way for a while. #Scientists #ContinentSized #Geological #Structure #Hiding #Beneath #AntarcticaAntarctica,Geology,mapping,Plate tectonics")
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