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Ankylosaur: New armoured dinosaur discovered

Two Vectipelta barretti - copyright Stuart Pond
Two Vectipelta barretti – copyright Stuart Pond

A new armoured dinosaur, known as an ankylosaur, has been described and named for Prof Paul Barrett of the Natural History Museum.

Vectipelta barretti was discovered in the Wessex formation on the Isle of Wight and represents the first armoured dinosaur from the dinosaur Isle to be described in 142 years.

Lead author Stuart Pond explained the importance of this find, ‘This is an important specimen because it sheds light on ankylosaur diversity within the Wessex formation and Early Cretaceous England.

‘For virtually 142 years, all ankylosaur remains from the Isle of Wight have been assigned to Polacanthus foxii, a famous dinosaur from the island, now all of those finds need to be revisited because we’ve described this new species.’

The new species differs from Polacanthus foxii, previously the only known ankylosaur from the Isle of Wight, in several key characteristics. The fossilized remains show differences in the neck and back vertebrae, a very different structure to the pelvis and more blade-like spiked armour.

The researchers used phylogenetic analysis to work out the relationships between different ankylosaurs and discovered that they are not actually very closely related. In fact, Vectipelta was found to be most closely related to some Chinese ankylosaurs, suggesting dinosaurs moved freely from Asia to Europe in the Early Cretaceous.

Vectipelta barretti would have been roaming the earth during the Early Cretaceous, a time for which fossil remains are rare worldwide. This has led some to suggest that a mass extinction occurred at the end of the Jurassic, which makes the understanding of dinosaur diversity at this time crucial to understanding if such an event occurred and how life recovered. With rocks from this time mostly absent in North America, the Wessex Formation and the Isle of Wight are hugely important areas in answering these questions.

At the time the Isle of Wight would have had a climate similar to that of the Mediterranean and was a flood plain covered by a large meandering river system. Floods would have washed organic material such as plants, logs and even dinosaur bodies together and, as waters receded, this organic matter would have been isolated in ponds on the floodplain that eventually dried out and were buried in the clay soil, preserving this organic material as the fossils we find today.

On naming the new dinosaur for Prof Paul Barrett of the Natural History Museum, senior author Dr Susannah Maidment said, ‘Myself and some of the other authors on this study have been mentored or supervised by Paul for most of our careers, and it was notable to us that Paul hadn’t had a dinosaur named after him yet. He’s hugely influential in in vertebrate palaeontology, and he’s a world-leading authority on dinosaurs.

‘We really wanted to thank him for his support and mentorship, so we decided to name a, slow-moving, spikey organism after him.’

Prof Paul Barrett has worked at the Natural History Museum, London for 20 years and in that time has published an impressive 220 scientific papers. He has also supervised 31 PhD students and mentored many others, encouraging a whole new generation of palaeontologists.

Of the honour Prof Barrett said, ‘I’m flattered and absolutely delighted to have been recognised in this way, not least as the first paper I ever wrote was also on an armoured dinosaur in the NHM collections. I’m sure that any physical resemblance is purely accidental.’

The team are optimistic that more species will be discovered in the area in the future. Dr Maidment concluded, ‘We have new iguanodontians that we are lining up, to be prepped and to be studied. I think we have at least two new taxa in the collections. With regards to ankylosaurs, they are somewhat rarer, so I think we need to keep our eyes peeled.’

The new dinosaur is part of the internationally important collection held at Dinosaur Isle Museum, operated by the Isle of Wight Council. Parts of the dinosaur will be on display at the museum for the school holidays. The bones have been cleaned from their surrounding matrix by staff and volunteers at the museum which has made the research possible.

Reference:
Stuart Pond, Sarah-Jane Strachan, Thomas J. Raven, Martin I. Simpson, Kirsty Morgan, Susannah C. R. Maidment. Vectipelta barretti, a new ankylosaurian dinosaur from the Lower Cretaceous Wessex Formation of the Isle of Wight, UK. Journal of Systematic Palaeontology, 2023; 21 (1) DOI: 10.1080/14772019.2023.2210577

Note: The above post is reprinted from materials provided by Taylor & Francis Group.

First side-necked turtle ever discovered in UK

The fossil was found on a National Trust beach on the Isle of Wight
The fossil was found on a National Trust beach on the Isle of Wight

The first side-necked turtle ever to be found in the UK has been discovered by an amateur fossil collector and palaeontologists at the University of Portsmouth.

The fossil remains are the earliest of a so-called side-necked pan-pleurodiran turtle, named as such because they fold their neck into their shell sideways when threatened. This does mean they can only see out with one eye.

Originally found on a National Trust beach on the Isle of Wight, the turtle fossil is an almost complete shell with cervical, dorsal and caudal vertebrae, scapulae, pelvic girdle and appendicular bones. Sadly, the skull was missing.

Lead author, Megan Jacobs, said: “This is an amazing discovery because it’s the first time this type of turtle has been found in the UK. Even more exciting is that we used a new technique of radiometric dating to determine the age of the fossil beyond any doubt. And to top it off, CT scanning revealed all the tiny bones inside. It’s really incredible for what looks like a rolled beach pebble!”

Megan and colleagues dissected minerals from inside the turtle shell and analysed them for uranium and lead. By measuring the ratio of lead to radioactive uranium, they established the turtle was from the Lower Cretaceous period, around 127 million years ago.

The fossil was originally found on the foreshore at Brook Bay on the southwest coast of the Isle of Wight by fossil collector Steve Burbridge. This part of the coast is well-known for fossil vertebrates that come from the cliff and foreshore exposures of the upper part of the famous Isle of Wight fossil beds of the Wessex Formation.

This is the first time that radiometric dating has been used on a fossil from the Wessex formation.

Megan added: “We’ve nicknamed the turtle ‘Burby’ after Steve who very kindly donated the specimen to the Dinosaur Isle Museum at Sandown on the Isle of Wight.”

The researchers also used cutting-edge micro CT scanning at the University of Portsmouth’s Future Technology Centre to discern various tiny bones. This advanced imaging technique provided invaluable insight into the structure and composition of the turtle’s shell, without damaging it.

Steve said: “It’s beyond my wildest dreams to have one of my finds published. I could never have guessed it was such an incredibly important fossil. It’s so wonderful to see all the tiny bones inside too.”

Geologist, Dr Catherine Mottram, from the University of Portsmouth’s School of the Environment, Geography and Geosciences is one of the paper’s co-authors. She said: “It is exciting that we have been able to use cutting edge radiometric dating techniques to provide absolute constraints for this important sequence for the first time.”

Other co-authors include Adán Pérez-García and Marcos Martín-Jiménez from UNED, Spain, Professor David Martill, Andrew Gale and Charles Wood from the University of Portsmouth, and Oliver Mattsson from Dinosaur Expeditions.

The paper is published in the scientific journal Cretaceous Research.

Reference:
Megan L. Jacobs, Adán Pérez-García, Marcos Martín-Jiménez, Catherine M. Mottram, David M. Martill, Andrew S. Gale, Oliver L. Mattsson, Charles Wood. A well preserved pan-pleurodiran (Dortokidae) turtle from the English Lower Cretaceous and the first radiometric date for the Wessex Formation (Hauterivian–Barremian) of the Isle of Wight, United Kingdom. Cretaceous Research, 2023; 150: 105590 DOI: 10.1016/j.cretres.2023.105590

Note: The above post is reprinted from materials provided by University of Portsmouth.

Scientists unearth 20 million years of ‘hot spot’ magmatism under Cocos plate

Mantle plumes, shown in red, have been identified around the world. (Ingo Wölbern, via Wikimedia Commons)
Mantle plumes, shown in red, have been identified around the world. (Ingo Wölbern, via Wikimedia Commons)

Ten years ago, Samer Naif made an unexpected discovery in Earth’s mantle: a narrow pocket, proposed to be filled with magma, hidden some 60 kilometers beneath the seafloor of the Cocos Plate.

Mantle melts are buoyant and typically float toward the surface — think underwater volcanoes that erupt to form strings of islands. But Naif’s imaging instead showed a clear slice of semi-molten rock: low-degree partial melts, still sandwiched at the base of the plate some 37 miles beneath the ocean floor.

Then, the observation provided an explanation for how tectonic plates can gradually slide, lubricated by partial melting. The study also “raised several questions about why magma is stored in a thin channel — and where the magma originated from,” says Naif, an assistant professor in the School of Earth and Atmospheric Sciences at Georgia Institute of Technology.

Fellow researchers went on to share competing interpretations for the cause of the channel — including studies that argued against magma being needed to explain the observation.

So Naif went straight to the source.

“I basically went on a multiyear hunt, akin to a Sherlock Holmes detective story, looking for clues of mantle magmas that we first observed in the 2013 Nature study,” he says. “This involved piecing together evidence from several independent sources, including geophysical, geochemical, and geological (direct seafloor sampling) data.”

Now, the results of that search are detailed in a new Science Advances article, “Episodic intraplate magmatism fed by a long-lived melt channel of distal plume origin,” authored by Naif and researchers from the U.S. Geological Survey at Woods Hole Coastal and Marine Science Center, Northern Arizona University, Lamont-Doherty Earth Observatory of Columbia University, the Department of Geology and Geophysics at Woods Hole Oceanographic Institution, and GNS Science of Lower Hutt, New Zealand.

Zeroing in

A relatively young oceanic plate — some 23 million years old — the Cocos Plate traces down the western coast of Central America, veering west to the Pacific Plate, then north to meet the North American Plate off the Pacific coast of Mexico.

Sliding between these two plates caused the devastating 1985 Mexico City earthquake and the 2017 Chiapas earthquake, while similar subduction between the Cocos and Caribbean plates resulted in the 1992 Nicaragua tsunami and earthquake, and the 2001 El Salvador earthquakes.

Scientists study the edges of these oceanic plates to understand the history and formation of volcanic chains — and to help researchers and agencies better prepare for future earthquakes and volcanic activity.

It’s in this active area that Naif and fellow researchers recently set out to document a series of magmatic intrusions just beneath the seafloor, in the same area that the team first detected the channel of magma back in 2013.

Plumbing the depths

For the new study, the team combined geophysical, geochemical, and seafloor drilling results with seismic reflection data, a technique used to image layers of sediments and rocks below the surface. “It helps us to see the geology where we cannot see it with our own eyes,” Naif explains.

First, the researchers observed an abundance of widespread intraplate magmatism. “Volcanism where it is not expected,” Naif says, “basically away from plate boundaries: subduction zones and mid-ocean ridges.”

Think Hawaii, where “a mantle plume of hot, rising material melts during its ascent, and then forms the Hawaii volcanic chain in the middle of the Pacific Ocean,” just as with the Cocos Plate, where the team imaged the volcanism fed by magma at the lithosphere-asthenosphere boundary — the base of the sliding tectonic plates.

“Below it is the convecting mantle,” Naif adds. “The tectonic plates are moving around on Earth’s surface because they are sliding on the asthenosphere below them.”

The researchers also found that this channel below the lithosphere is regionally extensive — over 100,000 square kilometers — and is a “long-lived feature that originated from the Galápagos Plume,” a mantle plume that formed the volcanic Galápagos islands, supplying melt for a series of volcanic events across the past 20 million years, and persisting today.

Importantly, the new study also suggests that these plume-fed melt channels may be widespread and long-lived sources for intraplate magmatism itself — as well as for mantle metasomatism, which happens when Earth’s mantle reacts with fluids to form a suite of minerals from the original rocks.

Connecting the (hot spot) dots

“This confirms that magma was there in the past — and some of it leaked through the mantle and erupted near the seafloor,” Naif says, “in the form of sill intrusions and seamounts: basically volcanoes located on the seafloor.”

The work also provides compelling supporting evidence that magma could still be stored in the channel. “More surprising is that the erupted magma has a chemical fingerprint that links its source to the Galápagos mantle plume.”

“We learned that the magma channel has been around for at least 20 million years, and on occasion some of that magma leaks to the seafloor where it erupts volcanically,” Naif adds.

The team’s identified source of the magma, the Galápagos Plume, “is more than 1,000 kilometers away from where we detected this volcanism. It is not clear how magma can stay around in the mantle for such a long time, only to leak out episodically.”

Plume hunters wanted

The evidence that the team compiled is “really quite subtle and requires a detailed and careful study of a suite of seafloor observations to connect the dots,” Naif says. “Basically, the signs of such volcanism, while they are quite clear here, also require high resolution data and several different types of data to be able to detect such subtle seafloor features.”

So, “if we can see such subtle clues of volcanism here,” Naif explains, “it means a similar, careful analysis of high resolution data in other parts of the seafloor may lead to similar discoveries of volcanism elsewhere, caused by other mantle plumes.”

“There are numerous mantle plumes dotted across the planet. There are also numerous seamounts — at least 100,000 of them! — covering the seafloor, and it is anyone’s guess how many of them formed in the middle of the tectonic plates because of magma sourced from distant mantle plumes that leaked to the surface.”

Naif looks forward to continuing that search, from seafloor to asthenosphere.

Reference:
Samer Naif, Nathaniel C. Miller, Donna J. Shillington, Anne Bécel, Daniel Lizarralde, Dan Bassett, Sidney R. Hemming. Episodic intraplate magmatism fed by a long-lived melt channel of distal plume origin. Science Advances, 2023; 9 (23) DOI: 10.1126/sciadv.add3761

Note: The above post is reprinted from materials provided by Georgia Institute of Technology.

Newly discovered Jurassic fossils in Texas

Steve May, a research associate at the Jackson School of Geosciences, holds a fossil from a plesiosaur, an extinct marine reptile. Credit: Jackson School of Geosciences/ The University of Texas at Austin.
Steve May, a research associate at the Jackson School of Geosciences, holds a fossil from a plesiosaur, an extinct marine reptile. Credit: Jackson School of Geosciences/ The University of Texas at Austin.

A team led by scientists at The University of Texas at Austin has filled a major gap in the state’s fossil record — describing the first known Jurassic vertebrate fossils in Texas.

The weathered bone fragments are from the limbs and backbone of a plesiosaur, an extinct marine reptile that would have swum the shallow sea that covered what is now northeastern Mexico and far western Texas about 150 million years ago.

The bones were discovered in the Malone Mountains of West Texas during two fossil hunting missions led by Steve May, a research associate at UT Austin’s Jackson School of Geosciences Museum of Earth History.

Before the discovery, the only fossils from the Jurassic that had been collected and described from outcrops in Texas were from marine invertebrates, such as ammonites and snails. May said that the new fossil finds serve as solid proof that Jurassic bones are here.

“Folks, there are Jurassic vertebrates out there,” May said. “We found some of them, but there’s more to be discovered that can tell us the story of what this part of Texas was like during the Jurassic.”

A paper describing the bones and other fossils was published in Rocky Mountain Geology on June 23.

The Jurassic was an iconic prehistoric era when giant dinosaurs walked the Earth. The only reason we humans know about them, and other Jurassic life, is because of fossils they left behind.

But to find Jurassic-aged fossils, you need Jurassic-aged rocks. Because of the geological history of Texas, the state hardly has any outcrops from this time in Earth history. The 13 square miles of Jurassic-aged rocks in the Malone Mountains make up most of those rocks in the state.

In 2015, when May learned while researching a book that there were no Jurassic bones in the Texas fossil record, he decided to go to the Malone Mountains to explore.

“You just don’t want to believe that there are no Jurassic bones in Texas,” May said. “Plus, there was a tantalizing clue.”

The clue was a mention of large bone fragments in a 1938 paper on the geology of the Malone Mountains by Claude Albritton, who later became a geology professor at Southern Methodist University (SMU). It was enough of a lead to get May and his collaborators out to West Texas to see for themselves. Large bone fragments are what they found. The plesiosaur fossils are eroded and broken up.

But it’s a start that could lead to more science, said co-author Louis Jacobs, a professor emeritus at SMU.

“Geologists are going to go out there looking for more bones,” Jacobs said. “They’re going to find them, and they’re going to look for the other things that interest them in their own special ways.”

Today, the Malone Mountains rise above the dry desert landscape. During the Jurassic, the sediments were deposited just below sea level probably within miles of the shoreline.

The team found several other specimens that give a look into the ancient shallow marine environment, such as petrified driftwood filled with burrows from marine worms and the shells of clams, snails and ammonites. The researchers found a range of plant fossils, including a pinecone, and wood with possible growth rings.

Globally, Jurassic plant fossils from lower latitudes close to the Earth’s equator are relatively rare, said co-author and paleobotanist Lisa Boucher, the director of the Jackson School’s Non-Vertebrate Paleontology Lab. She said the plant finds should make the Malones a place of interest to other paleobotanists and those interested in paleoenvironmental reconstruction.

Scientists have been conducting research in the Malones for over 100 years. So, why did it take so long to bring back Jurassic bones? May has several ideas — from remoteness of the area and permitting, to the research interests of past scientists. Whatever the reasons, Boucher said that the team’s discovery of a Texas first shows the value of field work — simply traveling to a place to see what’s there.

“It’s frequently part of the scientific process,” Boucher said. “There’re a few lines buried in an old publication, and you think ‘surely somebody has already looked at that,’ but often they haven’t. You need to delve into it.”

The study’s additional co-authors are Kenneth Bader, a laboratory manager at the Jackson School Museum of Earth History; Joshua Lively, the curator of paleontology at Utah State University and a Jackson School alumnus; and Timothy Myers and Michael Polcyn, both researchers at Southern Methodist University.

Reference:
Steven R. May, Kenneth S. Bader, Lisa D. Boucher, Louis L. Jacobs, Joshua R. Lively, Timothy S. Myers, Michael J. Polcyn. A record of Late Jurassic vertebrates from Texas. Rocky Mountain Geology, 2023; 58 (1): 19 DOI: 10.24872/rmgjournal.58.1.19

Note: The above post is reprinted from materials provided by University of Texas at Austin.

A Tongan volcano plume produced the most intense lightning rates ever detected

Powerful volcanic eruptions produce ash plumes that can create their own weather systems, providing the conditions for lightning at higher altitudes than normally seen.
Powerful volcanic eruptions produce ash plumes that can create their own weather systems, providing the conditions for lightning at higher altitudes than normally seen.

New research published in the journal Geophysical Research Letters showed that the plume emitted by the Hunga Volcano eruption in 2022 created the highest lightning flash rates ever recorded on Earth, more than any storm ever documented.

“The eruption of Hunga Volcano was the largest volcanic explosion since Krakatau in 1883,” said Sonja Behnke, of Los Alamos National Laboratory’s Electromagnetic Sciences and Cognitive Space Applications group and author on the paper.

Powerful volcanic eruptions produce ash plumes that can create their own weather systems, providing the conditions for lightning at higher altitudes than normally seen. When the undersea volcano in Tonga erupted, it created a plume that went more than 25 miles higher than typical thunderstorms. Lightning was observed at stratospheric altitudes (12 to 18 miles), where the air pressure is too low to support thunderstorm-like lightning. This fast-rising volcanic plume may have created locally higher pressures to support the environment necessary for lightning.

After reaching its maximum height, the plume expanded outward as an umbrella cloud, creating fast-moving circular ripples known as gravity waves, similar to a rock dropped in a pond. Donut-shaped rings of lightning expanded with the umbrella cloud and were as large as 174 miles in diameter. Similar “lightning holes” have been observed in thunderstorms, but never on this large of a scale.

The lightning was detected by space-based optical sensors, and global networks of ground-based radio antennas thousands of miles away.

The research team, led by the US Geological Survey Cascades Volcano Observatory, found that the eruption produced 2,615 flashes per minute at its peak intensity, which lasted nearly five minutes. This peak lightning rate is significantly higher than the second most intense lightning event ever detected — 993 flashes per minute — in a thunderstorm over the southern United States in 1999.

Remote detection of lightning helped create a detailed timeline of this historic eruption, and demonstrated the value of using volcanic lightning for monitoring volcanic activity.

“Lightning observations such as these reveal detail about the evolution of an eruption over time, which is particularly valuable when cloud-cover obscures satellite observations of a plume,” said Behnke.

The work was supported by the U.S. Geological Survey Volcano Hazards Program, the Laboratory Directed Research and Development program at Los Alamos National Laboratory and a NASA ROSES-2019 “Earth Science Research from Operational Geostationary Satellite Systems” program award.

Reference:
Alexa R. Van Eaton, Jeff Lapierre, Sonja A. Behnke, Chris Vagasky, Christopher J. Schultz, Michael Pavolonis, Kristopher Bedka, Konstantin Khlopenkov. Lightning Rings and Gravity Waves: Insights Into the Giant Eruption Plume From Tonga’s Hunga Volcano on 15 January 2022. Geophysical Research Letters, 2023; 50 (12) DOI: 10.1029/2022GL102341

Note: The above post is reprinted from materials provided by DOE/Los Alamos National Laboratory.

Earth’s solid metal sphere is ‘textured’

Inner Earth. Credit: Gary Hincks/Science Photo Library
Inner Earth. Credit: Gary Hincks/Science Photo Library

At the center the Earth is a solid metal ball, a kind of “planet within a planet,” whose existence makes life on the surface possible, at least as we know it.

How Earth’s inner core formed, grew and evolved over time remains a mystery, one that a team of University of Utah-led researchers is seeking to plumb with the help of seismic waves from naturally occurring earthquakes. While this 2,442-kilometer-diameter sphere comprises less than 1% of the Earth’s total volume, its existence is responsible for the planet’s magnetic field, without which Earth would be a much different place.

But the inner core is not the homogenous mass that was once assumed by scientists, but rather it’s more like a tapestry of different “fabric,” according to Guanning Pang, a former PhD student in the U.’s Department of Geology and Geophysics.

“For the first time we confirmed that this kind of inhomogeneity is everywhere inside the inner core,” Pang said. Now a post-doctoral researcher at Cornell University, Pang is the lead author of a new study, published July 5 in Nature that opens a window into the deepest reaches of Earth. He conducted the study as part of his PhD dissertation at Utah.

The other final frontier

“What our study was about was trying to look inside the inner core,” said U seismologist Keith Koper, who oversaw the study. “It’s like a frontier area. Anytime you want to image the interior of something, you have to strip away the shallow effects. So this is the hardest place to make images, the deepest part, and there’s still things that are unknown about it.”

This research harnessed a special dataset generated by a global network of seismic arrays set up to detect nuclear blasts. In 1996, the United Nations established the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization, CTBTO, to ensure compliance with the international treaty that bans such explosions.

Its centerpiece is the International Monitoring System (IMS), featuring four systems for detecting explosions using advanced sensing instruments sited all over the world. While their purpose is to enforce an international ban on nuclear detonations, they have yielded troves of data scientists can use to shed new light on what’s going on in Earth’s interior, oceans and atmosphere.

This data has facilitated research that illuminated meteor blasts, identified a colony of pygmy blue whales, advanced weather prediction, and provided insights into how icebergs form.

While Earth’s surface has been thoroughly mapped and characterized, its interior is much harder to study since it cannot be directly accessed. The best tools for sensing this hidden realm are earthquakes’ seismic waves propagating from the planet’s thin crust and vibrating through its rocky mantle and metallic core.

“The planet formed from asteroids that were sort of accreting [in space]. They’re running into each other and you generate a lot of energy. So the whole planet, when it’s forming up, is melting,” Koper said. “It’s simply that the iron is heavier and you get what we call core formation. The metals sink to the middle, and the liquid rock is outside, and then it essentially freezes over time. The reason all the metals are down there is because they’re heavier than the rocks.”

Planet within a planet

For the past few years, Koper’s lab has been analyzing seismic data senstivite to the inner core. A previous study, led by Pang identified variations between the rotations of Earth and its inner core that may have triggered a shift in the length of the day in 2001 to 2003.

Earth’s core, which measures about 4,300 miles across, is comprised mostly of iron and some nickel, along with a few other elements. The outer core remains liquid, enveloping the solid inner core.

“It’s like a planet within a planet that has its own rotation and it’s decoupled by this big ocean of molten iron,” said Koper, a geology professor who directs the U of U Seismograph Stations, or UUSS.

The protective field of magnetic energy surrounding Earth is created by convection occurring within the liquid outer core, which extends 2,260 kilometers (1,795 miles) above the solid core, he said. The molten metal rises above the solid inner core, cools as it approaches Earth’s rocky mantle and sinks. This circulation generates the bands of electrons enveloping the planet. Without Earth’s solid inner core, this field would be much weaker and the planetary surface would be bombarded with radiation and solar winds that would strip away the atmosphere and render the surface uninhabitable.

For the new study, the U team looked at seismic data recorded by 20 arrays of seismometers placed around the world including two in Antarctica. The closest to Utah is outside Pinedale, Wyo. These instruments are inserted in boreholes drilled up to 10 meters into granite formations and arranged in patterns to concentrate the signals they receive, similar to the way parabolic antennae work.

Pang analyzed seismic waves from 2,455 earthquakes, all exceeding magnitude 5.7, or about the strength of the 2020 quake that rocked Salt Lake City. The way these waves bounced off the inner core help map its internal structure.

Smaller quakes do not generate waves strong enough to be useful for the study.

“This signal that comes back from the inner core is really tiny. The size is about on the order of a nanometer,” Koper said. “What we’re doing is looking for a needle in a haystack. So these baby echoes and reflections are very hard to see.”

The core is changing

Scientists first used seismic waves to determine that the inner core was solid in 1936. Before the discovery by Danish seismologist Inge Lehmann, it was assumed the entire core was liquid since it is exceedingly hot, approaching 10,000 degrees Fahrenheit, about the temperature on the sun’s surface.

At some point in Earth’s history, the inner core started “nucleating,” or solidifying, under the intense pressures existing at the center of the planet. It remains unknown when that process began, but the U team gleaned important clues from the seismic data, which revealed a scattering effect associated with waves that penetrated to the core’s interior.

“Our biggest discovery is the inhomogeneity tends to be stronger when you get deeper. Toward the center of the Earth it tends to be stronger,” Pang said.

“We think that this fabric is related to how fast the inner core was growing. A long time ago the inner core grew really fast. It reached an equilibrium, and then it started to grow much more slowly,” Koper said. “Not all of the iron became solid, so some liquid iron could be trapped inside.”

Participating in the study, which was funded by the National Science Foundation, were researchers from University of Southern California, the Université de Nantes in France, and the Los Alamos National Laboratory.

Reference:
Guanning Pang, Keith D. Koper, Sin-Mei Wu, Wei Wang, Marine Lasbleis, Garrett Euler. Enhanced inner core fine-scale heterogeneity towards Earth’s centre. Nature, 2023; DOI: 10.1038/s41586-023-06213-2

Note: The above post is reprinted from materials provided by University of Utah. Original written by Brian Maffly.

Dinosaurs were the first to take the perspectives of others

Dinosaur Photo: MICHAEL ROSSKOTHEN/MostPhotos
Dinosaur
Photo: MICHAEL ROSSKOTHEN/MostPhotos

When someone near you turns their head towards something in the environment, you likely can’t help to follow their gaze direction. This reaction is observed in mammals, birds and even reptiles alike. It’s an effective way to gather information about what caught the attention of your fellow, which you might otherwise have missed. However, a far more advanced behavior is to follow someone’s gaze to a location that is initially obstructed from your view. By repositioning yourself to see what the other person is looking at, you demonstrate an understanding that the other has a different perspective. This ability, known as visual perspective taking develops in children between the ages of one-and-a-half to two years and serves as the foundation for later comprehending referential communication and that others have minds that differ from your own.

Visual perspective taking has, to date, only been found in very few species. Mainly in apes and some monkeys, but also in dogs and crow birds. However, there is limited knowledge regarding the evolutionary origins of this crucial social skill. A team of researchers from Lund University aimed to investigate a potential early emergence of visual perspective taking in dinosaurs. Through a comparison of alligators with the most primitive existing birds, known as palaeognaths, they discovered that visual perspective taking originated in the dinosaur lineage likely 60 million years, or more, prior to its appearance in mammals.

Crocodilians are the closest living relatives to birds. Their neuroanatomy has remained largely unchanged for hundreds of millions of years, and is similar to that of the common ancestor of dinosaurs and crocodilians. Palaeognath birds comprise the ostrich birds, such as emus and rheas, but also the flighted tinamous. Their brains are in large parts comparable to their forebearers, the non- avian paravian dinosaurs, which feature such celebrities as the velociraptors. Comparing these two groups of animals creates a bracket around the extinct lineage of dinosaurs leading up to modern birds.

The study revealed that alligators do not demonstrate visual perspective taking, although they do follow gaze to a visible location. In contrast, all tested bird species exhibited visual perspective taking. Additionally, the birds engaged in a behaviour called “checking back,” where the observer looks back into the eyes of the gazer, and re-tracks the gaze, when unable to find anything in the direction of their gaze the first time. This behaviour indicates an expectation that the gaze is referring to a target in the environment. Previously, this has only been observed in humans, apes and monkeys, and ravens.

Palaeognath birds emerged 110 million years ago, predating the two mammal groups endowed with visual perspective taking — primates and dogs — with 60 million years. Considering the neuroanatomical similarities between these birds and their non-avian forebearers, it is plausible that the skill originated even earlier in the dinosaur lineage. However, it is less likely to have been present among the earliest dinosaurs, which had more alligator-like brains. Maybe future research will show the ability to be more widespread among mammals than currently known, but even if that would be the case it will most probably still be predated by the dinosaur origin. Nevertheless, it is not surprising that visual perspective taking emerged earlier in the dinosaurs, which include the birds, given their superior vision compared to most mammals, that historically relied on nocturnal adaptations. It was only with the emergence of the primates and certain carnivores that our visual capabilities improved.

This is yet another finding that calls into question the prevailing view that mammals drove the evolution of complex cognition, and that they are the cognitive yardstick to which other animals should be compared. An increasing number of studies show the remarkable neurocognition of the avian dinosaurs, the birds, which might prompt a rethinking of the natural history of cognition.

Comments from the authors:

Senior author, prof. Mathias Osvath: “Early in my career, crow birds earned the nickname “feathered apes,” due to numerous research findings that showcased their remarkable cognition. However, I’m beginning to question whether it would be more fitting to consider primates as honorary birds.”

First author (then PhD-student), Dr Claudia Zeiträg: “Birds are commonly being overlooked when it comes to their cognitive skills. Our findings show that they do not only have several cognitive skills on par with those of apes, but that their forebearers most likely had these skills long before they evolved in mammals.”

Middle author, Dr Stephan Reber: “Crocodilians are ideal models to study the evolutionary origins of cognitive capacities in birds. What they share most probably existed in the common ancestor of dinosaurs and crocodilians. If crocodilians lack an ability birds possess, it likely evolved in the dinosaur lineage after the split. This approach allows us to study the cognition of extinct species.”

Reference:
Claudia Zeiträg, Stephan A. Reber, Mathias Osvath. Gaze following in Archosauria—Alligators and palaeognath birds suggest dinosaur origin of visual perspective taking. Science Advances, 2023; 9 (20) DOI: 10.1126/sciadv.adf0405

Note: The above post is reprinted from materials provided by Lund University.

Giants of the Jurassic seas were twice the size of a killer whale

An artist’s impression of the pliosaur by Megan Jacobs, University of Portsmouth
An artist’s impression of the pliosaur by Megan Jacobs, University of Portsmouth

Over 20 years ago, the BBC’s Walking with Dinosaurs TV documentary series showed a 25-metre long Liopleurodon. This sparked heated debates over the size of this pliosaur as it was thought to have been wildly overestimated and more likely to have only reached an adult size of just over six metres long.

The speculation was set to continue, but now a chance discovery in an Oxfordshire museum has led to University of Portsmouth palaeontologists publishing a paper on a similar species potentially reaching a whopping 14.4 metres — twice the size of a killer whale.

Professor David Martill from the University of Portsmouth’s School of the Environment, Geography and Geosciences, said: “I was a consultant for the BBC’s pilot programme ‘Cruel Sea’ and I hold my hands up — I got the size of Liopleurodon horrendously wrong. I based my calculations on some fragmentary material which suggested a Liopleurodon could grow to a length of 25 metres, but the evidence was scant and it caused a lot of controversy at the time.

“The size estimate on the BBC back in 1999 was overdone, but now we have some evidence that is much more reliable after a serendipitous discovery of four enormous vertebrate.”

Professor Martill’s co-author, Megan Jacobs, was photographing an ichthyosaur skeleton at Abingdon County Hall Museum, while Dave looked through drawers of fossils. He found a large vertebra and was thrilled to discover the curator had three more of them in storage.

The vertebrae are clearly identifiable as being closely related to a Pliosaurus species or similar animal. Pliosaurs were like plesiosaurs, but with a bigger elongated head, similar to a crocodile, and a shorter neck. They had four flippers, which acted as powerful paddles to propel them through water and a relatively short tail.

After conducting topographic scans, Professor Martill and colleagues calculated this Late Jurassic marine reptile could have grown to between 9.8 and 14.4 metres long.

He said: “We know these pliosaurs were very fearsome animals swimming in the seas that covered Oxfordshire 145-152 million years ago. They had a massive skull with huge protruding teeth like daggers — as big, if not bigger than a T. rex, and certainly more powerful.

“They were at the top of the marine food chain and probably preyed on ichthyosaurs, long-necked plesiosaurs and maybe even smaller marine crocodiles, simply by biting them in half and taking chunks off them. We know they were massacring smaller marine reptiles because you can see bite marks in ichthyosaur bones in examples on display in The Etches Collection in Dorset.”

The vertebrae were originally discovered during temporary excavations at Warren Farm in the River Thames Valley in Oxfordshire and come from the Kimmeridge Clay Formation. This deposit is Late Jurassic in age, around 152 million years old.

Professor Martill added: “It’s wonderful to prove there was indeed a truly gigantic pliosaur species in the Late Jurassic seas. Although not yet on a par with the claims made for Liopleurodon in the iconic BBC TV series Walking With Dinosaurs, it wouldn’t surprise me if one day we find some clear evidence that this monstrous species was even bigger.”

Reference:
David M. Martill, Megan L. Jacobs, Roy E. Smith. A truly gigantic pliosaur (Reptilia, Sauropterygia) from the Kimmeridge Clay Formation (Upper Jurassic, Kimmeridgian) of England. Proceedings of the Geologists’ Association, 2023; DOI: 10.1016/j.pgeola.2023.04.005

Note: The above post is reprinted from materials provided by University of Portsmouth.

Fossil of mosasaur with bizarre ‘screwdriver teeth’ found in Morocco

The strange ridges on the teeth indicate a specialised feeding strategy, however its diet remains a mystery. (Photo by Dr Nick Longrich)
The strange ridges on the teeth indicate a specialised feeding strategy, however its diet remains a mystery. (Photo by Dr Nick Longrich)

Scientists have discovered a new species of mosasaur, a sea-dwelling lizard from the age of the dinosaurs, with strange, ridged teeth unlike those of any known reptile. Along with other recent finds from Africa, it suggests that mosasaurs and other marine reptiles were evolving rapidly up until 66 million years ago, when they were wiped out by an asteroid along with the dinosaurs and around 90% of all species on Earth.

The new species, Stelladens mysteriosus, comes from the Late Cretaceous of Morocco and was around twice the size of a dolphin.

It had a unique tooth arrangement with blade-like ridges running down the teeth, arranged in a star-shaped pattern, reminiscent of a cross-head screwdriver.

Most mosasaurs had two bladelike, serrated ridges on the front and back of the tooth to help cut prey, however Stelladens had anywhere from four to six of these blades running down the tooth.

“It’s a surprise,” said Dr Nick Longrich from the Milner Centre for Evolution at the University of Bath, who led the study. “It’s not like any mosasaur, or any reptile, even any vertebrate we’ve seen before.”

Dr Nathalie Bardet, a marine reptile specialist from the Museum of Natural History in Paris, said: “I’ve worked on the mosasaurs of Morocco for more than 20 years, and I’d never seen anything like this before — I was both perplexed and amazed!”

That several teeth were found with the same shape suggests their strange shape was not the result of a pathology or a mutation.

The unique teeth suggest a specialised feeding strategy, or a specialised diet, but it remains unclear just what Stelladens ate.

Dr Longrich said: “We have no idea what this animal was eating, because we don’t know of anything similar either alive today, or from the fossil record.

“It’s possible it found a unique way to feed, or maybe it was filling an ecological niche that simply doesn’t exist today. The teeth look like the tip of a Phillips-head screwdriver, or maybe a hex wrench.

“So what’s it eating? Phillips head screws? IKEA furniture? Who knows.”

The teeth were small, but stout and with wear on the tips, which seemed to rule out soft-bodied prey. The teeth weren’t strong enough to crush heavily armoured animals like clams or sea urchins, however.

“That might seem to suggest it’s eating something small, and lightly armoured — thin-shelled ammonites, crustaceans, or bony fish — but it’s hard to know,” said Longrich. “There were weird animals living in the Cretaceous- ammonites, belemnites, baculites — that no longer exist. It’s possible this mosasaur ate something, and occupied a niche, that simply doesn’t exist anymore, and that might explain why nothing like this is ever seen again.

“Evolution isn’t always predictable. Sometimes it goes off in a unique direction, and something evolves that’s never been seen before, and then it never evolves again.”

The mosasaurs lived alongside dinosaurs but weren’t dinosaurs. Instead, they were giant lizards, relatives of Komodo dragons, snakes, and iguanas, adapted for a life at sea.

Mosasaurs evolved around 100 million years ago, and diversified up to 66 million years ago, when a giant asteroid hit the Yucatan Peninsula in Mexico, plunging the world into darkness.

Although scientists have debated the role of environmental changes towards the end of the Cretaceous in the extinction, Stelladens, along with recent discoveries from of Morocco, suggests that mosasaurs were evolving rapidly up to the very end — they went out at their peak, rather than fading away.

The new study shows that even after years of work in the Cretaceous of Morocco, new species are continuing to be discovered. The reason may be that most species are rare.

The authors of the study predict that in a very diverse ecosystem, it may take decades to find all of the rare species.

“We’re not even close to finding everything in these beds,” said Longrich, “This is the third new species to appear, just this year. The amount of diversity at the end of the Cretaceous is just staggering.”

Nour-Eddine Jalil, a professor at the Natural History Museum and a researcher at Univers Cadi Ayyad in Morocco, said: “The fauna has produced an incredible number of surprises — mosasaurs with teeth arranged like a saw, a turtle with a snout in the form of snorkel, a multitude of vertebrates of various shapes and sizes, and now a mosasaur with star-shaped teeth.

“We would say the works of an artist with an overflowing imagination.

“Morocco’s sites offer an unparalleled picture of the amazing biodiversity just before the great crisis of the end of the Cretaceous.”

Reference:
Nicholas R. Longrich, Nour-Eddine Jalil, Xabier Pereda-Suberbiola, Nathalie Bardet. Stelladens mysteriosus: A Strange New Mosasaurid (Squamata) from the Maastrichtian (Late Cretaceous) of Morocco. Fossils, 2023; 1 (1): 2 DOI: 10.3390/fossils1010002

Note: The above post is reprinted from materials provided by University of Bath.

River erosion can shape fish evolution

An MIT study of the freshwater greenfin darter fish suggests river erosion can be a driver of biodiversity in tectonically inactive regions.Credits: Image: Jose-Luis Olivares/MIT with fish photo by Isaac Szabo
An MIT study of the freshwater greenfin darter fish suggests river erosion can be a driver of biodiversity in tectonically inactive regions.
Credits:
Image: Jose-Luis Olivares/MIT with fish photo by Isaac Szabo

New findings could explain biodiversity hotspots in tectonically quiet regions.

If we could rewind the tape of species evolution around the world and play it forward over hundreds of millions of years to the present day, we would see biodiversity clustering around regions of tectonic turmoil. Tectonically active regions such as the Himalayan and Andean mountains are especially rich in flora and fauna due to their shifting landscapes, which act to divide and diversify species over time.

But biodiversity can also flourish in some geologically quieter regions, where tectonics hasn’t shaken up the land for millennia. The Appalachian Mountains are a prime example: The range has not seen much tectonic activity in hundreds of millions of years, and yet the region is a notable hotspot of freshwater biodiversity.

Now, an MIT study identifies a geological process that may shape the diversity of species in tectonically inactive regions. In a paper appearing in Science, the researchers report that river erosion can be a driver of biodiversity in these older, quieter environments.

They make their case in the southern Appalachians, and specifically the Tennessee River Basin, a region known for its huge diversity of freshwater fishes. The team found that as rivers eroded through different rock types in the region, the changing landscape pushed a species of fish known as the greenfin darter into different tributaries of the river network. Over time, these separated populations developed into their own distinct lineages.

The team speculates that erosion likely drove the greenfin darter to diversify. Although the separated populations appear outwardly similar, with the greenfin darter’s characteristic green-tinged fins, they differ substantially in their genetic makeup. For now, the separated populations are classified as one single species.

“Give this process of erosion more time, and I think these separate lineages will become different species,” says Maya Stokes PhD ’21, who carried out part of the work as a graduate student in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS).

The greenfin darter may not be the only species to diversify as a consequence of river erosion. The researchers suspect that erosion may have driven many other species to diversify throughout the basin, and possibly other tectonically inactive regions around the world.

“If we can understand the geologic factors that contribute to biodiversity, we can do a better job of conserving it,” says Taylor Perron, the Cecil and Ida Green Professor of Earth, Atmospheric, and Planetary Sciences at MIT.

The study’s co-authors include collaborators at Yale University, Colorado State University, the University of Tennessee, the University of Massachusetts at Amherst, and the Tennessee Valley Authority (TVA). Stokes is currently an assistant professor at Florida State University.

Fish in trees

The new study grew out of Stokes’ PhD work at MIT, where she and Perron were exploring connections between geomorphology (the study of how landscapes evolve) and biology. They came across work at Yale by Thomas Near, who studies lineages of North American freshwater fishes. Near uses DNA sequence data collected from freshwater fishes across various regions of North America to show how and when certain species evolved and diverged in relation to each other.

Near brought a curious observation to the team: a habitat distribution map of the greenfin darter showing that the fish was found in the Tennessee River Basin — but only in the southern half. What’s more, Near had mitochondrial DNA sequence data showing that the fish’s populations appeared to be different in their genetic makeup depending on the tributary in which they were found.

To investigate the reasons for this pattern, Stokes gathered greenfin darter tissue samples from Near’s extensive collection at Yale, as well as from the field with help from TVA colleagues. She then analyzed DNA sequences from across the entire genome, and compared the genes of each individual fish to every other fish in the dataset. The team then created a phylogenetic tree of the greenfin darter, based on the genetic similarity between fish.

From this tree, they observed that fish within a tributary were more related to each other than to fish in other tributaries. What’s more, fish within neighboring tributaries were more similar to each other than fish from more distant tributaries.

“Our question was, could there have been a geological mechanism that, over time, took this single species, and splintered it into different, genetically distinct groups?” Perron says.

A changing landscape

Stokes and Perron started to observe a “tight correlation” between greenfin darter habitats and the type of rock where they are found. In particular, much of the southern half of the Tennessee River Basin, where the species abounds, is made of metamorphic rock, whereas the northern half consists of sedimentary rock, where the fish are not found.

They also observed that the rivers running through metamorphic rock are steeper and more narrow, which generally creates more turbulence, a characteristic greenfin darters seem to prefer. The team wondered: Could the distribution of greenfin darter habitat have been shaped by a changing landscape of rock type, as rivers eroded into the land over time?

To check this idea, the researchers developed a model to simulate how a landscape evolves as rivers erode through various rock types. They fed the model information about the rock types in the Tennessee River Basin today, then ran the simulation back to see how the same region may have looked millions of years ago, when more metamorphic rock was exposed.

They then ran the model forward and observed how the exposure of metamorphic rock shrank over time. They took special note of where and when connections between tributaries crossed into non-metamorphic rock, blocking fish from passing between those tributaries. They drew up a simple timeline of these blocking events and compared this to the phylogenetic tree of diverging greenfin darters. The two were remarkably similar: The fish seemed to form separate lineages in the same order as when their respective tributaries became separated from the others.

“It means it’s plausible that erosion through different rock layers caused isolation between different populations of the greenfin darter and caused lineages to diversify,” Stokes says.

This research was supported, in part, by the Terra Catalyst Fund and the U.S. National Science Foundation through the AGeS Geochronology Program and the Graduate Research Fellowship Program. While at MIT, Stokes received support through the Martin Fellowship for Sustainability and the Hugh Hampton Young Fellowship.

Reference:
Maya F. Stokes, Daemin Kim, Sean F. Gallen, Edgar Benavides, Benjamin P. Keck, Julia Wood, Samuel L. Goldberg, Isaac J. Larsen, Jon Michael Mollish, Jeffrey W. Simmons, Thomas J. Near, J. Taylor Perron. Erosion of heterogeneous rock drives diversification of Appalachian fishes. Science, 2023; 380 (6647): 855 DOI: 10.1126/science.add9791

Note: The above post is reprinted from materials provided by Massachusetts Institute of Technology. Original written by Jennifer Chu.

Eruption of Tonga underwater volcano found to disrupt satellite signals halfway around the world

Eruption of Tonga underwater volcano found to disrupt satellite signals halfway around the world.Credit: ERG science center
Eruption of Tonga underwater volcano found to disrupt satellite signals halfway around the world.
Credit: ERG science center

An international team has used satellite- and ground-based ionospheric observations to demonstrate that an air pressure wave triggered by volcanic eruptions could produce an equatorial plasma bubble (EPB) in the ionosphere, severely disrupting satellite-based communications. Their findings were published in the journal Scientific Reports.

The ionosphere is the region of the Earth’s upper atmosphere where molecules and atoms are ionized by solar radiation, creating positively charged ions. The area with the highest concentration of ionized particles is called the F-region, an area 150 to 800 km above the Earth’s surface. The F-region plays a crucial role in long-distance radio communication, reflecting and refracting radio waves used by satellite and GPS tracking systems back to the Earth’s surface.

These important transmissions can be disrupted by irregularities in the F-region. During the day, the ionosphere is ionized by the Sun’s ultraviolet radiation, creating a density gradient of electrons with the highest density near the equator. However, disruptions to this, such as the movement of plasma, electric fields, and neutral winds, can cause the formation of a localized irregularity of enhanced plasma density. This region can grow and evolve, creating a bubble-like structure called an EPB. EPB can delay radio waves and degrade the performance of GPS.

Since these density gradients can be affected by atmospheric waves, it has long been hypothesized that they are formed by terrestrial events such as volcanic activity. For an international team led by Designated Assistant Professor Atsuki Shinbori (he, him) and Professor Yoshizumi Miyoshi (he, him) of the Institute for Space-Earth Environmental Research (ISEE), Nagoya University, in collaboration with NICT, The University of Electro-Communications, Tohoku University, Kanazawa University, Kyoto University and ISAS, the Tonga volcano eruption offered them a perfect opportunity to test this theory.

The Tonga volcano eruption was the biggest submarine eruption in history. This allowed the team to test their theory using the Arase satellite to detect EPB occurrences, the Himawari-8 satellite to check the initial arrival of air pressure waves and ground-based ionospheric observations to track the motion of the ionosphere. They observed an irregular structure of the electron density across the equator that occurred after the arrival of pressure waves generated by the volcanic eruption.

“The results of this study showed EPBs generated in the equatorial to low-latitude ionosphere in Asia in response to the arrival of pressure waves caused by undersea volcanic eruptions off Tonga,” Shinbori said.

The group also made a surprising discovery. For the first time, they showed that ionospheric fluctuations start a few minutes to a few hours earlier than the atmospheric pressure waves involved in the generation of plasma bubbles. This could have important implications because it suggests that the long-held model of geosphere-atmosphere-cosmosphere coupling, which states that ionospheric disturbances only happen after the eruption, needs revision.

“Our new finding is that the ionospheric disturbances are observed several minutes to hours before the initial arrival of the shock waves triggered by the Tonga volcanic eruption,” Shinbori said. “This suggests that the propagation of the fast atmospheric waves in the ionosphere triggered the ionospheric disturbances before the initial arrival of the shock waves. Therefore, the model needs to be revised to account for these fast atmospheric waves in the ionosphere.”

They also found that the EPB extended much further than predicted by the standard models. “Previous studies have shown that the formation of plasma bubbles at such high altitudes is a rare occurrence, making this a very unusual phenomenon,” Shinbori said. “We found that the EPB formed by this eruption reached space even beyond the ionosphere, suggesting that we should pay attention to the connection between the ionosphere and the cosmosphere when extreme natural phenomenon, such as the Tonga event, occur.”

“The results of this research are significant not only from a scientific point of view but also from the point of view of space weather and disaster prevention,” he said. “In the case of a large-scale event, such as the Tonga volcano eruption, observations have shown that a hole in the ionosphere can form even under conditions that are considered unlikely to occur under normal circumstances. Such cases have not been incorporated into space weather forecast models. This study will contribute to the prevention of satellite broadcasting and communication failures associated with ionospheric disturbances caused by earthquakes, volcanic eruptions, and other events.”

Reference:
Atsuki Shinbori, Takuya Sori, Yuichi Otsuka, Michi Nishioka, Septi Perwitasari, Takuo Tsuda, Atsushi Kumamoto, Fuminori Tsuchiya, Shoya Matsuda, Yoshiya Kasahara, Ayako Matsuoka, Satoko Nakamura, Yoshizumi Miyoshi, Iku Shinohara. Generation of equatorial plasma bubble after the 2022 Tonga volcanic eruption. Scientific Reports, 2023; 13 (1) DOI: 10.1038/s41598-023-33603-3

Note: The above post is reprinted from materials provided by Nagoya University.

Extinct offshore volcano could store gigatons of carbon dioxide

Annotated seismic cross-section of the Fontanelas volcano. Source: Pereira and Gamboa, 2023
Annotated seismic cross-section of the Fontanelas volcano. Source: Pereira and Gamboa, 2023

A new study published in Geology concludes that an extinct volcano off the shore of Portugal could store as much as 1.2-8.6 gigatons of carbon dioxide, the equivalent of ~24-125 years of the country’s industrial emissions. For context, in 2022 a total of 42.6 megatons (0.0426 gigatons) of carbon dioxide was removed from the atmosphere by international carbon capture and storage efforts, according to the Global CCS Institute. The new study suggests that carbon capture and storage in offshore underwater volcanoes could be a promising new direction for removal and storage of much larger volumes of the greenhouse gas from the atmosphere.

“We know that most countries, including Portugal, are making efforts to decarbonize the economy and our human activities, this is a message that this may be one of the instruments to solve the problem” says Ricardo Pereira, a geologist at the NOVA School of Science and Technology, and co-author of the study.

Storing carbon dioxide in an extinct volcano would rely on a process known as ‘in situ mineral carbonation.’ In this process, carbon dioxide reacts with elements in certain types of rocks to produce new minerals that safely and permanently store the carbon dioxide. Elements like calcium, magnesium, and iron combine with carbon dioxide to form the minerals calcite, dolomite, and magnesite, respectively. Rocks that contain large amounts of calcium, iron, and magnesium are ideal candidates for this process — such as the volcanic basalts that make up most of the sea floor. Knowing this, the researchers targeted an offshore volcano for a few reasons — the structure of the volcano could provide an ideal architecture for carbon injection and storage, the rocks are the right type for the reactions involved, and the location Is not too close to large populations, but also not too far.

Most carbon capture projects have relied on injection of carbon dioxide into porous sedimentary basins that are sealed to prevent migration of the gas out of reservoirs. In these cases, the carbon will eventually start to form minerals, but only over longer periods of time — decades to centuries. In 2016, researchers published findings that 95% of carbon dioxide injected into underground basalts in Iceland had mineralized within just two years. The much shorter mineralization time makes the process safer and more effective — once carbon is stored in minerals, issues like potential leaks are no longer a concern.

Davide Gamboa, a geologist at the University of Aveiro and co-author of the study, explains, “What makes mineral carbonation really interesting is the time. The faster it gets into a mineral, the safer it becomes, and once it’s a mineral, it is permanent.”

The researchers studied the storage potential at the ancient Fontanelas volcano, which is partially buried ~100 kilometers offshore from Lisbon, with a peak ~1500 meters below sea-level.

To estimate the potential volume of carbon dioxide that could be stored at this site, the authors used 2D and 3D seismic studies of the undersea volcano that had been produced during offshore oil exploration, as well as data from samples that had been dredged from the area in 2008. The dredged samples contained naturally formed carbonate minerals, indicating that the chemical reactions required to store carbon were already happening, and that intentional efforts to mineralize carbon in these rocks should be successful. The samples also had up to 40% pore space — meaning there are spaces within the rocks where carbon dioxide could be injected and mineralized. The researchers also indicate that low-permeability layers imaged around the flanks of the volcano could help with containing the carbon dioxide before it is mineralized.

While this study demonstrated a large potential carbon storage capacity at the Fontanelas volcano, the authors highlight that many other places around the world may have similar offshore volcanoes that could be candidates for carbon capture and storage.

Reference:
Ricardo Pereira, Davide Gamboa. In situ carbon storage potential in a buried volcano. Geology, 2023; DOI: 10.1130/G50965.1

Note: The above post is reprinted from materials provided by Geological Society of America.

Iron-rich rocks unlock new insights into Earth’s planetary history

Metamorphosed banded iron formation from southern Wyoming showing deformation and folding. The rock is approximately 2.7 billion years old. Dark bands are iron oxides (magnetite, hematite) and yellow-orange bands are chert with iron oxide inclusions (jasper). (Photo by Linda Welzenbach-Fries/Rice University)
Metamorphosed banded iron formation from southern Wyoming showing deformation and folding. The rock is approximately 2.7 billion years old. Dark bands are iron oxides (magnetite, hematite) and yellow-orange bands are chert with iron oxide inclusions (jasper). (Photo by Linda Welzenbach-Fries/Rice University)

Visually striking layers of burnt orange, yellow, silver, brown and blue-tinged black are characteristic of banded iron formations, sedimentary rocks that may have prompted some of the largest volcanic eruptions in Earth’s history, according to new research from Rice University.

The rocks contain iron oxides that sank to the bottom of oceans long ago, forming dense layers that eventually turned to stone. The study published this week in Nature Geoscience suggests the iron-rich layers could connect ancient changes at Earth’s surface — like the emergence of photosynthetic life — to planetary processes like volcanism and plate tectonics.

In addition to linking planetary processes that were generally thought to be unconnected, the study could reframe scientists’ understanding of Earth’s early history and provide insight into processes that could produce habitable exoplanets far from our solar system.

“These rocks tell — quite literally — the story of a changing planetary environment,” said Duncan Keller, the study’s lead author and a postdoctoral researcher in Rice’s Department of Earth, Environmental and Planetary Sciences. “They embody a change in the atmospheric and ocean chemistry.”

Banded iron formations are chemical sediments precipitated directly from ancient seawater rich in dissolved iron. Metabolic actions of microorganisms, including photosynthesis, are thought to have facilitated the precipitation of the minerals, which formed layer upon layer over time along with chert (microcrystalline silicon dioxide). The largest deposits formed as oxygen accumulated in Earth’s atmosphere about 2.5 billion years ago.

“These rocks formed in the ancient oceans, and we know that those oceans were later closed up laterally by plate tectonic processes,” Keller explained.

The mantle, though solid, flows like a fluid at about the rate that fingernails grow. Tectonic plates — continent-sized sections of the crust and uppermost mantle — are constantly on the move, largely as a result of thermal convection currents in the mantle. Earth’s tectonic processes control the life cycles of oceans.

“Just like the Pacific Ocean is being closed today — it’s subducting under Japan and under South America — ancient ocean basins were destroyed tectonically,” he said. “These rocks either had to get pushed up onto continents and be preserved — and we do see some preserved, that’s where the ones we’re looking at today come from — or subducted into the mantle.”

Because of their high iron content, banded iron formations are denser than the mantle, which made Keller wonder whether subducted chunks of the formations sank all the way down and settled in the lowest region of the mantle near the top of Earth’s core. There, under immense temperature and pressure, they would have undergone profound changes as their minerals took on different structures.

“There’s some very interesting work on the properties of iron oxides at those conditions,” Keller said. “They can become highly thermally and electrically conductive. Some of them transfer heat as easily as metals do. So it’s possible that, once in the lower mantle, these rocks would turn into extremely conductive lumps like hot plates.”

Keller and his co-workers posit that regions enriched in subducted iron formations might aid the formation of mantle plumes, rising conduits of hot rock above thermal anomalies in the lower mantle that can produce enormous volcanoes like the ones that formed the Hawaiian Islands. “Underneath Hawaii, seismological data show us a hot conduit of upwelling mantle,” Keller said. “Imagine a hot spot on your stove burner. As the water in your pot is boiling, you’ll see more bubbles over a column of rising water in that area. Mantle plumes are sort of a giant version of that.”

“We looked at the depositional ages of banded iron formations and the ages of large basaltic eruption events called large igneous provinces, and we found that there’s a correlation,” Keller said. “Many of the igneous events — which were so massive that the 10 or 15 largest may have been enough to resurface the entire planet — were preceded by banded iron formation deposition at intervals of roughly 241 million years, give or take 15 million. It’s a strong correlation with a mechanism that makes sense.”

The study showed that there was a plausible length of time for banded iron formations to first be drawn deep into the lower mantle and to then influence heat flow to drive a plume toward Earth’s surface thousands of kilometers above.

In his effort to trace the journey of banded iron formations, Keller crossed disciplinary boundaries and ran into unexpected insights.

“If what’s happening in the early oceans, after microorganisms chemically change surface environments, ultimately creates an enormous outpouring of lava somewhere else on Earth 250 million years later, that means these processes are related and ‘talking’ to each other,” Keller said. “It also means it’s possible for related processes to have length scales that are far greater than people expected. To be able to infer this, we’ve had to draw on data from many different fields across mineralogy, geochemistry, geophysics and sedimentology.”

Keller hopes the study will spur further research. “I hope this motivates people in the different fields that it touches,” he said. “I think it would be really cool if this got people talking to each other in renewed ways about how different parts of the Earth system are connected.”

Keller is part of the CLEVER Planets: Cycles of Life-Essential Volatile Elements in Rocky Planets program, an interdisciplinary, multi-institutional group of scientists led by Rajdeep Dasgupta, Rice’s W. Maurice Ewing Professor of Earth Systems Science in the Department of Earth, Environmental and Planetary Sciences.

“This is an extremely interdisciplinary collaboration that’s looking at how volatile elements that are important for biology — carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur — behave in planets, at how planets acquire these elements and the role they play in potentially making planets habitable,” Keller said.

“We’re using Earth as the best example that we have, but we’re trying to figure out what the presence or absence of one or some of these elements might mean for planets more generally,” he added.

Cin-Ty Lee, Rice’s Harry Carothers Wiess Professor of Geology, Earth, Environmental and Planetary Sciences, and Dasgupta are co-authors on the study. Other co-authors are Santiago Tassara, an assistant professor at Bernardo O’Higgins University in Chile, and Leslie Robbins, an assistant professor at the University of Regina in Canada, who both did postdoctoral work at Yale University, and Yale Professor of Earth and Planetary Sciences Jay Ague, Keller’s doctoral adviser.

NASA (80NSSC18K0828) and the Natural Sciences and Engineering Research Council of Canada (RGPIN-2021-02523) supported the research.

Reference:
Duncan S. Keller, Santiago Tassara, Leslie J. Robbins, Cin-Ty A. Lee, Jay J. Ague, Rajdeep Dasgupta. Links between large igneous province volcanism and subducted iron formations. Nature Geoscience, 2023; DOI: 10.1038/s41561-023-01188-1

Note: The above post is reprinted from materials provided by Rice University. Original written by Silvia Cernea Clark.

Study presents new clues about the rise of Earth’s continents

A microscope image from an experiment conducted for this study. The image contains glass (brown), large garnets (pink) and other small mineral crystals. The field of view is 410 microns wide, about size of a sugar crystal. Credit: Science (2023). DOI: 10.1126/science.ade3418
A microscope image from an experiment conducted for this study. The image contains glass (brown), large garnets (pink) and other small mineral crystals. The field of view is 410 microns wide, about size of a sugar crystal. Credit: Science (2023). DOI: 10.1126/science.ade3418

Continents are part of what makes Earth uniquely habitable for life among the planets of the solar system, yet surprisingly little is understood about what gave rise to these huge pieces of the planet’s crust and their special properties. New research from Elizabeth Cottrell, research geologist and curator of rocks at the Smithsonian’s National Museum of Natural History, and lead study author Megan Holycross, formerly a Peter Buck Fellow and National Science Foundation Fellow at the museum and now an assistant professor at Cornell University, deepens the understanding of Earth’s crust by testing and ultimately eliminating one popular hypothesis about why continental crust is lower in iron and more oxidized compared to oceanic crust. The iron-poor composition of continental crust is a major reason why vast portions of the Earth’s surface stand above sea level as dry land, making terrestrial life possible today.

The study, published today in Science, uses laboratory experiments to show that the iron-depleted, oxidized chemistry typical of Earth’s continental crust likely did not come from crystallization of the mineral garnet, as a popular explanation proposed in 2018.

The building blocks of new continental crust issue forth from the depths of the Earth at what are known as continental arc volcanoes, which are found at subduction zones where an oceanic plate dives beneath a continental plate. In the garnet explanation for continental crust’s iron-depleted and oxidized state, the crystallization of garnet in the magmas beneath these continental arc volcanoes removes non-oxidized (reduced or ferrous, as it is known among scientists) iron from the terrestrial plates, simultaneously depleting the molten magma of iron and leaving it more oxidized.

One of the key consequences of Earth’s continental crust’s low iron content relative to oceanic crust is that it makes the continents less dense and more buoyant, causing the continental plates to sit higher atop the planet’s mantle than oceanic plates. This discrepancy in density and buoyancy is a major reason that the continents feature dry land while oceanic crusts are underwater, as well as why continental plates always come out on top when they meet oceanic plates at subduction zones.

The garnet explanation for the iron depletion and oxidation in continental arc magmas was compelling, but Cottrell said one aspect of it did not sit right with her.

“You need high pressures to make garnet stable, and you find this low-iron magma at places where crust isn’t that thick and so the pressure isn’t super high,” she said.

In 2018, Cottrell and her colleagues set about finding a way to test whether the crystallization of garnet deep beneath these arc volcanoes is indeed essential to the process of creating continental crust as is understood. To accomplish this, Cottrell and Holycross had to find ways to replicate the intense heat and pressure of the Earth’s crust in the lab, and then develop techniques sensitive enough to measure not just how much iron was present, but to differentiate whether that iron was oxidized.

To recreate the massive pressure and heat found beneath continental arc volcanoes, the team used what are called piston-cylinder presses in the museum’s High-Pressure Laboratory and at Cornell. A hydraulic piston-cylinder press is about the size of a mini fridge and is mostly made of incredibly thick and strong steel and tungsten carbide. Force applied by a large hydraulic ram results in very high pressures on tiny rock samples, about a cubic millimeter in size. The assembly consists of electrical and thermal insulators surrounding the rock sample, as well as a cylindrical furnace. The combination of the piston-cylinder press and heating assembly allows for experiments that can attain the very high pressures and temperatures found under volcanoes.

In 13 different experiments, Cottrell and Holycross grew samples of garnet from molten rock inside the piston-cylinder press under pressures and temperatures designed to simulate conditions inside magma chambers deep in Earth’s crust. The pressures used in the experiments ranged from 1.5 to 3 gigapascals — that is roughly 15,000 to 30,000 Earth atmospheres of pressure or 8,000 times more pressure than inside a can of soda. Temperatures ranged from 950 to 1,230 degrees Celsius, which is hot enough to melt rock.

Next, the team collected garnets from Smithsonian’s National Rock Collection and from other researchers around the world. Crucially, this group of garnets had already been analyzed so their concentrations of oxidized and unoxidized iron were known.

Finally, the study authors took the materials from their experiments and those gathered from collections to the Advanced Photon Source at the U.S. Department of Energy’s Argonne National Laboratory in Illinois. There the team used high-energy X-ray beams to conduct X-ray absorption spectroscopy, a technique that can tell scientists about the structure and composition of materials based on how they absorb X-rays. In this case, the researchers were looking into the concentrations of oxidized and unoxidized iron.

The samples with known ratios of oxidized and unoxidized iron provided a way to check and calibrate the team’s X-ray absorption spectroscopy measurements and facilitated a comparison with the materials from their experiments.

The results of these tests revealed that the garnets had not incorporated enough unoxidized iron from the rock samples to account for the levels of iron-depletion and oxidation present in the magmas that are the building blocks of Earth’s continental crust.

“These results make the garnet crystallization model an extremely unlikely explanation for why magmas from continental arc volcanoes are oxidized and iron depleted,” Cottrell said. “It’s more likely that conditions in Earth’s mantle below continental crust are setting these oxidized conditions.”

Like so many results in science, the findings lead to more questions: “What is doing the oxidizing or iron depleting?” Cottrell asked. “If it’s not garnet crystallization in the crust and it’s something about how the magmas arrive from the mantle, then what is happening in the mantle? How did their compositions get modified?”

Cottrell said that these questions are hard to answer but that now the leading theory is that oxidized sulfur could be oxidizing the iron, something a current Peter Buck Fellow is investigating under her mentorship at the museum.

This study is an example of the kind of research that museum scientists will tackle under the museum’s new Our Unique Planet initiative, a public-private partnership, which supports research into some of the most enduring and significant questions about what makes Earth special. Other research will investigate the source of Earth’s liquid oceans and how minerals may have served as templates for life.

This research was supported by funding from the Smithsonian, the National Science Foundation, the Department of Energy and the Lyda Hill Foundation.

Reference:
Megan Holycross, Elizabeth Cottrell. Garnet crystallization does not drive oxidation at arcs. Science, 2023; 380 (6644): 506 DOI: 10.1126/science.ade3418

Note: The above post is reprinted from materials provided by Smithsonian.

Golden fossils reveal origins of exceptional preservation

Ammonite fossil From the Ohmden quarry, Posidonia shale lagerstatte. Credit: Sinjini Sinha
Ammonite fossil From the Ohmden quarry, Posidonia shale lagerstatte. Credit: Sinjini Sinha

 

All that glitters is not gold, or even fool’s gold in the case of fossils.

A recent study by scientists at The University of Texas at Austin and collaborators found that many of the fossils from Germany’s Posidonia shale do not get their gleam from pyrite, commonly known as fool’s gold, which was long thought to be the source of the shine. Instead, the golden hue is from a mix of minerals that hints at the conditions in which the fossils formed.

The discovery is important for understanding how the fossils — which are among the world’s best-preserved specimens of sea life from the Early Jurassic — came to form in the first place, and the role that oxygen in the environment had in their formation.

“When you go to the quarries, golden ammonites peek out from black shale slabs,” said study co-author Rowan Martindale, an associate professor at the UT Jackson School of Geosciences. “But surprisingly, we struggled to find pyrite in the fossils. Even the fossils that looked golden, are preserved as phosphate minerals with yellow calcite. This dramatically changes our view of this famous fossil deposit.”

The research was published in Earth Science Reviews. Drew Muscente, a former assistant professor at Cornell College and former Jackson School postdoctoral researcher, led the study.

The fossils of the Posidonia Shale date back to 183 million years ago, and include rare soft-bodied specimens such as ichthyosaur embryos, squids with ink-sacs, and lobsters. To learn more about the fossilization conditions that led to such exquisite preservation, the researchers put dozens of samples under scanning electron microscopes to study their chemical composition.

“I couldn’t wait to get them in my microscope and help tell their preservational story,” said co-author Jim Schiffbauer, an associate professor at the University of Missouri Department of Geological Sciences, who handled some of the larger samples.

The researchers found that in every instance, the fossils were primarily made up of phosphate minerals even though the surrounding black shale rock was dotted with microscopic clusters of pyrite crystals, called framboids.

“I spent days looking for the framboids on the fossil,” said co-author Sinjini Sinha, a doctoral student at the Jackson School. “For some of the specimens, I counted 800 framboids on the matrix while there was maybe three or four on the fossils.”

The fact that pyrite and phosphate are found in different places on the specimens is important because it reveals key details about the fossilization environment. Pyrite forms in anoxic (without oxygen) environments, but phosphate minerals need oxygen. The research suggests that although an anoxic seafloor sets the stage for fossilization — keeping decay and predators at bay — it took a pulse of oxygen to drive the chemical reactions needed for fossilization.

These findings complement earlier research carried out by the team on the geochemical conditions of sites known for their caches of exceptionally preserved fossils, called konservat-lagerstätten. However, the results of these studies contradict long-standing theories about the conditions needed for exceptional fossil preservation in the Posidonia.

“It’s been thought for a long time that the anoxia causes the exceptional preservation, but it doesn’t directly help,” said Sinha. “It helps with making the environment conducive to faster fossilization, which leads to the preservation, but it’s oxygenation that’s enhancing preservation.”

It turns out, the oxygenation — and the phosphate and accompanying minerals — also enhanced the fossil’s shine.

The research was funded by Cornell College and the National Science Foundation. The Posidonia fossil specimens used in this study are now part of the collections at the Jackson School’s Non-Vertebrate Paleontology Laboratory.

Reference:
A.D. Muscente, Olivia Vinnes, Sinjini Sinha, James D. Schiffbauer, Erin E. Maxwell, Günter Schweigert, Rowan C. Martindale. What role does anoxia play in exceptional fossil preservation? Lessons from the taphonomy of the Posidonia Shale (Germany). Earth-Science Reviews, 2023; 238: 104323 DOI: 10.1016/j.earscirev.2023.104323

Note: The above post is reprinted from materials provided by University of Texas at Austin.

Deadly volcanic flow insights could aid forecasting

Pyroclastic flow. Credit: Gordon Simmons; Dr Eric Breard image credit: Dr Charline Lormand
Pyroclastic flow. Credit: Gordon Simmons; Dr Eric Breard image credit: Dr Charline Lormand

The discovery of the driving force behind the world’s deadliest volcanic events could help improve forecasting of their devastating effects, new research suggests.

The findings reveal the mechanism that enables dense, scorching avalanches of a mixture of rock, ash and gases ejected during volcanic eruptions—called pyroclastic flows—to travel at up to 100 miles per hour.

Better predicting the path of pyroclastic flows—which can reach temperatures of 600°C—could help prevent injuries and deaths following volcanic eruptions, researchers say.

More than 600 million people around the world live in regions that could be hit by pyroclastic flows.

The pyroclastic flow triggered by the eruption of Mount Vesuvius in 79 AD is one of the most famous examples of these lethal events.

While scientists have long been aware of the immense dangers they pose, the underlying mechanism that enables them to travel at such high speed and long distances—up to 12 miles—had remained unknown.

Fluid-like behavior

Now, a team led by an Edinburgh researcher has revealed the science behind so-called block-and-ash flows, the most common and destructive type of pyroclastic flow. Their work is published in the journal Nature Communications.

They identified a mechanism that greatly reduces the friction of the dense volcanic mixtures, enabling them to travel at high speed.

The process—called fragmentation-induced fluidization—causes the base layer of pyroclastic flows to exhibit fluid-like behavior.

This effect is triggered by rapidly compacting the mixture, and raising the pressure between fine particles after large blocks have disintegrated into powder.

This enhanced fluidity, coupled with the large amounts—often millions of tons—of volcanic material, is the reason pyroclastic flows can travel far at high speeds as dense avalanches, destroying everything in their path, the team says.

Density changes

The researchers conducted a comprehensive analysis by examining pyroclastic flow deposits from previous eruptions at Mount Merapi in Java, Indonesia, in 2006 and 2010.

They also carried out laboratory experiments and ran computer simulations to investigate the impact of density changes within pyroclastic flows and the ability of their granular mixtures to become fluid-like.

“The discovery of the fragmentation-induced fluidization process is hugely significant, as it enables us to develop more reliable numerical models that can accurately evaluate pyroclastic flow hazards around both current and potentially future active volcanoes. Our findings not only reveal a fundamental geoscience principle but also urges us to reconsider the focus of our field-based studies. This work lays the foundation for a multitude of investigations that my research group at University of Edinburgh will undertake, ultimately refining and reshaping our understanding of volcanic hazards,” says Dr. Eric Breard, School of GeoSciences.

Reference:
Eric C. P. Breard et al, The fragmentation-induced fluidisation of pyroclastic density currents, Nature Communications (2023). DOI: 10.1038/s41467-023-37867-1

Note: The above post is reprinted from materials provided by University of Edinburgh.

Rougher faults may generate more earthquake aftershocks

New lab work suggests that rock roughness affects earthquake aftershock dynamics along faults. Credit: Dextersinister/Wikimedia Commons, CC BY-SA 4.0
New lab work suggests that rock roughness affects earthquake aftershock dynamics along faults. Credit: Dextersinister/Wikimedia Commons, CC BY-SA 4.0

When an earthquake hits, it is rarely an isolated event. Foreshocks precede quakes, and aftershocks follow them. To quantify seismic hazards, scientists must disentangle the factors that contribute to these shaking sequences.

In recent years, advancements in laboratory methods have enabled deeper exploration of earthquake dynamics. Now, Goebel and colleagues present new lab findings highlighting how the roughness of the rocks sliding past each other in a fault zone may influence aftershocks.

The researchers created fractures of varying roughness in several granite cylinders ranging from 40 to 50 millimeters in diameter. Then they applied pressure to the fractured granite to simulate sliding motions along a fault. They measured the resulting seismic disturbances in high resolution in the form of acoustic emission wave measurements.

The result was a realistic and manipulable simulation of actual earthquakes: Spacing and timing of the main slips, foreshocks, and aftershocks in the granite cylinders resembled those of real-world Southern California earthquakes.

The researchers found that after a major slip along a fracture—analogous to a main earthquake along a fault—the granite cylinders underwent periods of relaxation of built-up stress as well as aftershocks. Fractures with greater roughness moved less along the fracture during the main slip event but had more aftershocks; smoother fractures had more slip but fewer aftershocks.

These findings suggest that in nature, fault surface roughness may play a key role in the production of aftershocks following a main earthquake event.

The research is published in the journal Geophysical Research Letters.

Reference:
Thomas H. W. Goebel et al, Fault Roughness Promotes Earthquake‐Like Aftershock Clustering in the Lab, Geophysical Research Letters (2023). DOI: 10.1029/2022GL101241

Note: The above post is reprinted from materials provided by American Geophysical Union.

The largest fossil crinoids ever

Periechocrinus, a Silurian crinoid. BGS © UKRI.
Periechocrinus, a Silurian crinoid. BGS © UKRI.

Introduction about Crinoids

What Are Crinoid Fossils?

Crinoids, also known as sea lilies or feather stars, are a group of marine animals that belong to the phylum Echinodermata. These creatures have been around for more than 500 million years, and they play an important role in the marine ecosystem. They are filter feeders, using their feather-like arms to capture plankton and other small organisms.

One of the interesting things about crinoids is that they have a complex anatomy that can be preserved in fossil form. The stem of a crinoid is made up of many small plates called ossicles, which are connected by flexible ligaments. The crown of the crinoid, which contains the feeding apparatus, is made up of a series of arms that are covered in small pinnules. These pinnules are used to capture plankton and other small organisms and bring them to the mouth of the crinoid.

Fossil crinoids come in many different shapes and sizes. Some crinoids have long, slender stems, while others have short, squat stems. The crowns of crinoids can also vary in shape and size, with some crowns being very small and others being quite large.

Where are crinoids found?

Fossil crinoids are often found in sedimentary rocks, which form when layers of sediment are deposited and compressed over time. These rocks can be found all over the world, and they can provide valuable information about the history of life on Earth. Fossil crinoids have been found in rocks dating back to the Ordovician period, which began around 485 million years ago.

In this article, we will explore some of the largest fossil crinoids ever discovered, including their size, location, and significance.

Taxocrinus saratogensis

One of the largest fossil crinoids ever discovered was found in the state of Indiana in the United States. The crinoid, which belongs to the species Taxocrinus saratogensis, was discovered in 1906 by a team of geologists led by John M. Clarke. The specimen is estimated to be around 350 million years old and is believed to have lived during the Devonian period.

The crinoid is incredibly large, with a stem measuring more than 40 feet in length and a crown that measures more than 10 feet in diameter. The entire specimen is estimated to have weighed more than 10 tons when it was alive. This makes it one of the largest fossil crinoids ever discovered.

The discovery of Taxocrinus saratogensis was an important event in the history of paleontology. At the time, it was the largest fossil crinoid ever discovered, and it provided valuable information about the morphology and biology of these ancient creatures. Today, the specimen is housed at the American Museum of Natural History in New York City.

Uintacrinus socialis

Another large fossil crinoid was discovered in the state of Missouri in the United States. The crinoid, which belongs to the species Uintacrinus socialis, was discovered in the early 20th century. The specimen is estimated to be around 300 million years old and is believed to have lived during the Carboniferous period.

The crinoid is also quite large, with a stem measuring more than 30 feet in length and a crown that measures around 6 feet in diameter. The entire specimen is estimated to have weighed more than 5 tons when it was alive.

The discovery of Uintacrinus socialis was significant because it provided valuable information about the evolution of crinoids. This species had a unique morphology that differed from other crinoids, and its discovery helped scientists to better understand the diversity of these ancient creatures.

Marsupitsa fragilis

In addition to the two specimens mentioned above, there have been many other impressive fossil crinoids discovered around the world. One of these is Marsupitsa fragilis, which was discovered in the United Kingdom in the 19th century.

The crinoid, which is estimated to be around 350 million years old, has a stem measuring around 20 feet in length and a crown measuring around 3 feet in diameter. The specimen is notable for its delicate and intricate morphology, which has been well-preserved in the fossil record.

The discovery of Marsupitsa fragilis was significant because it provided valuable information about the diversity and complexity of crinoids during the Devonian period. This species had a unique morphology that differed from other crinoids, and its discovery helped scientists to better understand the evolution of these ancient creatures.

Pachylocrinus nodosus

Another large fossil crinoid was discovered in the state of Texas in the United States. The crinoid, which belongs to the species Pachylocrinus nodosus, was discovered in the early 20th century. The specimen is estimated to be around 90 million years old and is believed to have lived during the Cretaceous period.

The crinoid is quite large, with a stem measuring around 20 feet in length and a crown measuring around 3 feet in diameter. The specimen is notable for its robust and heavily armored morphology, which has been well-preserved in the fossil record.

The discovery of Pachylocrinus nodosus was significant because it provided valuable information about the evolution of crinoids during the Cretaceous period. This species had a unique morphology that differed from other crinoids, and its discovery helped scientists to better understand the diversity of these ancient creatures.

Agaricocrinus americanus

Agaricocrinus americanus is another large fossil crinoid that was discovered in the state of Indiana in the United States. The crinoid is estimated to be around 350 million years old and has a stem measuring around 20 feet in length and a crown measuring around 3 feet in diameter.

The specimen is notable for its unusual morphology, which includes a crown that is shaped like a mushroom. This morphology is quite different from that of other crinoids, and its discovery has provided valuable information about the diversity of these ancient creatures during the Devonian period.

Encrinus liliiformis

Encrinus liliiformis is a large fossil crinoid that was discovered in Germany in the 19th century. The crinoid is estimated to be around 180 million years old and has a stem measuring around 10 feet in length and a crown measuring around 2 feet in diameter.

The specimen is notable for its delicate and intricate morphology, which has been well-preserved in the fossil record. The discovery of Encrinus liliiformis was significant because it provided valuable information about the diversity and complexity of crinoids during the Jurassic period.

Bathycrinus giganteus

Bathycrinus giganteus is a large fossil crinoid that was discovered in the Pacific Ocean in the 20th century. The crinoid is estimated to be around 35 million years old and has a stem measuring around 10 feet in length and a crown measuring around 1 foot in diameter.

The specimen is notable for its unusual morphology, which includes a crown that is shaped like a basket. This morphology is quite different from that of other crinoids, and its discovery has provided valuable information about the diversity of these ancient creatures during the Paleogene period.

Isocrinus nicoletti

Finally, we come to Isocrinus nicoletti, another large fossil crinoid that was discovered in the state of Indiana in the United States. The crinoid, which is estimated to be around 350 million years old, has a stem measuring around 20 feet in length and a crown measuring around 3 feet in diameter.

The specimen is notable for its unusual morphology, which includes a long, slender stem and a crown that is divided into numerous branches. This morphology is quite different from that of other crinoids, and its discovery has provided valuable information about the diversity of these ancient creatures during the Devonian period.

Conclusion

In conclusion, the discovery of large fossil crinoids is a testament to the incredible diversity of life that has existed on Earth throughout its history. These ancient creatures provide a glimpse into the past and help us to better understand the evolution of life on our planet. As scientists continue to study these fascinating fossils, we can expect to learn even more about the history of life on Earth.

What was the largest dinosaurs?

Argentinosaurus is still widely considered the heaviest dinosaur. Based on its mid-range estimate, it weighed the same as about nine T. rexes or 13 African elephants!
Argentinosaurus is still widely considered the heaviest dinosaur. Based on its mid-range estimate, it weighed the same as about nine T. rexes or 13 African elephants!

Introduction

Dinosaurs were some of the largest creatures to ever roam the earth. These prehistoric giants come in a variety of shapes and sizes, from the small and agile to the massive and lumbering. Among the most awe-inspiring of these creatures were the largest dinosaurs, massive beasts that could weigh up to 100 tons and stretch dozens of meters in length. In this article, we’ll take a closer look at some of the biggest and most impressive dinosaurs ever to have lived.

Patagotitan mayorum

The largest dinosaur discovered to date is the Patagotitan mayorum, a species of titanosaur that lived in what is now Argentina during the Late Cretaceous period (about 100 million years ago). This massive creature weighed an estimated 69 tons and measured around 122 feet (37 meters) in length. That’s longer than a basketball court! Its leg bones alone measured over 7 feet long.

Titanosaurs

Titanosaurs were a group of long-necked herbivores that lived during the Late Cretaceous period. They were among the last surviving dinosaurs before the mass extinction event that wiped out all non-avian dinosaurs about 66 million years ago. Titanosaurs were also some of the largest animals to ever walk the earth, with some species weighing up to 100 tons.

Argentinosaurus huinculensis

Another contender for the title of largest dinosaur is Argentinosaurus huinculensis, also a titanosaur that lived in what is now Argentina around 90 million years ago. This dinosaur is estimated to have weighed between 60 and 100 tons and measured up to 115 feet (35 meters) in length. However, the fossils of this dinosaur are fragmentary, so its exact size is difficult to determine.

Sauroposeidon proteles

Sauroposeidon proteles is another contender for the title of largest dinosaur. This dinosaur lived about 110 million years ago in what is now North America. Sauroposeidon was also a titanosaur, and it is estimated to have measured up to 56 feet (17 meters) tall, making it the tallest dinosaur ever discovered. However, its weight is estimated to have been around 55 tons, which is smaller than both Patagotitan and Argentinosaurus.

Dreadnoughtus schrani

Dreadnoughtus schrani is another giant titanosaur that lived in what is now Argentina about 77 million years ago. This dinosaur is estimated to have weighed around 65 tons and measured up to 85 feet (26 meters) in length. Like the other titanosaurs, Dreadnoughtus was a herbivore with a long neck and tail.

Spinosaurus aegypticus

Aside from the titanosaurs, there were other dinosaurs that were among the largest ever to have lived. For example, the Spinosaurus aegypticus was a massive theropod dinosaur that lived during the Late Cretaceous period in what is now North Africa. This dinosaur is estimated to have measured up to 59 feet (18 meters) in length and weighed around 12 tons. What made Spinosaurus unique among theropods was its elongated snout, which likely helped it catch fish in the rivers and lakes that it inhabited.

Giganotosaurus carolinii

Another massive theropod dinosaur was the Giganotosaurus carolinii, which lived in what is now Argentina during the Late Cretaceous period. This dinosaur is estimated to have measured up to 46 feet (14 meters) in length and weighed around 8 tons. Giganotosaurus was a relative of the more famous Tyrannosaurus rex, and it likely filled a similar ecological niche as a top predator.

Brachiosaurus altithorax

Finally, we have the long-necked sauropod dinosaur called the Brachiosaurus altithorax. This dinosaur lived during the Late Jurassic period in what is now North America, and it is estimated to have weighed around 88 tons and measured up to 85 feet (26 meters) in length. Brachiosaurus is famous for its long neck, which it used to reach high branches and leaves in trees.

So, which dinosaur was the largest? It’s difficult to say for sure, as different species have been estimated to be the largest based on different criteria. However, the Patagotitan mayorum is currently considered the largest dinosaur ever discovered based on its estimated weight and length. Of course, there may be even larger dinosaurs out there waiting to be discovered, so the title of “largest dinosaur” could change in the future.

Conclusion

In conclusion, the largest dinosaurs were among the most impressive creatures to ever walk the earth. These massive beasts included long-necked titanosaurs, powerful theropods, and towering sauropods. While we may never see these creatures in person, their fossils and remains continue to inspire awe and wonder among scientists and dinosaur enthusiasts alike.

Painite: The Most Unique Gemstone in the World

Natural 236.40 Ct Huge Red Painite Rough Burmese Facet Raw Loose GemstoneCredit: supremgem/etsy
Natural 236.40 Ct Huge Red Painite Rough Burmese Facet Raw Loose Gemstone
Credit: supremgem/etsy

Introduction

Gemstones have captivated humans for millennia with their beauty, rarity, and unique qualities. While there are countless gemstones known to us today, one gemstone stands out as the most unique and intriguing: Painite. Discovered in 1951, Painite is an incredibly rare and enigmatic gemstone whose formation is still not fully understood. In this article, we will explore the fascinating geological story of Painite, examining its formation process and the characteristics that make it the most unique gemstone in the world.

Discovery and Rarity

Painite was first discovered in Myanmar (formerly Burma) by British gemologist Arthur C.D. Pain, after whom the gemstone was named. For decades, only a few specimens were known to exist, making it one of the rarest gemstones on Earth. In fact, the Guinness World Records once listed Painite as the world’s rarest mineral. However, in recent years, more Painite deposits have been discovered, though the gemstone remains exceedingly rare and highly valuable.

Formation and Geological Context

Painite is a borate mineral with the chemical formula CaZrB(Al9O18). Its formation is thought to occur in metamorphic rocks, particularly in the contact zones between marbles and boron-rich granitic pegmatites. These pegmatites are formed when molten rock cools and crystallizes slowly, allowing the formation of large crystal structures. The presence of boron, an essential element in Painite’s composition, is a key factor in its formation.

Painite’s unique crystal structure is characterized by a hexagonal system, making it visually distinct from other gemstones. Its color varies from reddish-brown to dark brown and sometimes exhibits a slight orange hue. This unique gemstone also exhibits pleochroism, a phenomenon where the gemstone displays different colors when viewed from different angles.

The formation of Painite is a complex process that is not yet fully understood. Several factors are believed to contribute to its rarity, including the specific geological conditions required for its formation, the scarcity of its constituent elements, and the unique combination of pressure and temperature needed for the crystal to grow. Furthermore, Painite’s formation is thought to be associated with the presence of other rare minerals such as ruby, sapphire, and spinel, which are also found in the Mogok region of Myanmar where Painite was first discovered.

Significance and Value

The rarity and uniqueness of Painite make it a highly sought-after gemstone among collectors and connoisseurs. While its hardness, measured at 8 on the Mohs scale, makes it suitable for use in jewelry, its extreme scarcity means that most Painite specimens are preserved as mineral specimens in private collections or museums.

In recent years, Painite’s value has increased exponentially as its rarity has become more widely recognized. As more deposits are discovered, and our understanding of its formation process deepens, the fascination with this enigmatic gemstone is likely to continue. Painite serves as a testament to the wonders of Earth’s geological processes, providing a tangible reminder of the incredible diversity and beauty of the natural world.

Conclusion

Painite’s unique characteristics, geological context, and rarity make it the most unique gemstone in the world. Its formation process, while still not fully understood, is a fascinating story that highlights the complexity and wonder of Earth’s geological processes. As we continue to explore and uncover the mysteries of this exceptional gemstone, Painite will undoubtedly continue to captivate and inspire both scientists and gem enthusiasts alike.

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