How Nodules Stay on Top at the Bottom of the Sea

<div dir="ltr" style="text-align: left;" trbidi="on"> <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody> <tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-vmt2c90R0iw/Xh54aS9XkMI/AAAAAAAARzo/9aoYoVRL0qA1NtASpEh9cggWLodmzhMewCLcBGAsYHQ/s1600/How%2BNodules%2BStay%2Bon%2BTop%2Bat%2Bthe%2BBottom%2Bof%2Bthe%2BSea%2B%25282%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="750" data-original-width="1000" height="480" src="https://1.bp.blogspot.com/-vmt2c90R0iw/Xh54aS9XkMI/AAAAAAAARzo/9aoYoVRL0qA1NtASpEh9cggWLodmzhMewCLcBGAsYHQ/s640/How%2BNodules%2BStay%2Bon%2BTop%2Bat%2Bthe%2BBottom%2Bof%2Bthe%2BSea%2B%25282%2529.jpg" width="640" /></a></td></tr> <tr><td class="tr-caption" style="text-align: center;">Photo credit: Utah Geological Survey</td></tr> </tbody></table> <br /> <br /> <div style="text-align: left;"> <span style="font-family: "georgia" , "times new roman" , serif;">Rare metallic elements found in clumps on the deep-ocean floor mysteriously remain uncovered despite the shifting sands and sediment many leagues under the sea. Scientists now think they know why, and it could have important implications for mining these metals while preserving the strange fauna at the bottom of the ocean.</span><br /> <br /> The growth of these deep-sea nodules -- metallic lumps of manganese, iron, and other metals found in all the major ocean basins -- is one of the slowest known geological processes. These ringed concretions, which are potential sources of rare-earth and other critical elements, grow on average just 10 to 20 millimeters every million years. Yet in one of earth science's most enduring mysteries, they somehow manage to avoid being buried by sediment despite their locations in areas where clay accumulates at least 100 times faster than the nodules grow.<br /> <br /> Understanding how these agglomerations of metals remain on the open sea floor could help geoscientists provide advice on accessing them for industrial use. A new study published this month in Geology will help scientists understand this process better.<br /> <br /> "It is important that any mining of these resources is done in a way that preserves the fragile deep-sea environments in which they are found," said lead author Adriana Dutkiewicz, an ARC Future Fellow in the School of Geosciences at The University of Sydney.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> Rare-earth and other critical elements are essential for the development of technologies needed for low-carbon economies. They will play an increasingly important role for next-generation solar cells, efficient wind turbines, and rechargeable batteries that will power the renewables revolution.</div> <h4 style="text-align: left;"> <span style="font-family: "georgia" , "times new roman" , serif;">Solving the Enigma</span></h4> <div style="text-align: left;"> From scouring bottom currents to burrowing animals, researchers have proposed a number of mechanisms to account for this enigma. But solving it depends on a better understanding of where the nodules are situated and the environmental conditions that prevail there. Now a global study published in Geology uses predictive machine learning to investigate which factors control the location of polymetallic nodules. The results offer new insights to inform deep-sea mineral exploration as well as its regulation.<br /> <br /> "The International Seabed Authority is currently preparing new environmental regulations to govern deep-sea mining," Dr. Dutkiewicz said. "Our analysis represents a global, data-driven synthesis to impartially inform these policies and deep-ocean environmental management."<br /> <br /> Dr. Dutkiewicz and co-authors Dr. Alexander Judge and Professor Dietmar Müller combined open-access data for thousands of polymetallic nodules with global datasets of key environmental parameters to create a machine-learning model that ranks the factors controlling nodule location. The resulting map predicts where polymetallic nodules are most likely to occur.<br /> <br /> The authors were surprised to find that globally the nodules occur in regions where the bottom current speeds are far too slow to remove sediment. Instead, the nodules are associated with seafloor fauna.<br /> <br /> "Organisms such as star fish, octopods and molluscs seem to keep the nodules at the seafloor surface by foraging, burrowing and ingesting sediment on and around them," Dr. Dutkiewicz said. "Although these organisms occur in relatively low concentrations on the abyssal seafloor, they are still abundant enough to locally affect sediment accumulation."<br /> <br /> This insight is supported by direct seafloor observations of nodule fields by independent studies. "Our conclusion is that deep-sea ecosystems and nodules are inextricably connected," Dr. Dutkiewicz said.<br /> <br /> The study results also suggest that the regions where nodules are most likely to occur are more extensive than what has previously been assumed and include vast areas that are yet to be explored -- findings with important industrial as well as conservation implications.<br /> <br /> "Our map highlights regions that may be important economically," Dr. Dutkiewicz said, "but at the same time draws attention to areas of the seafloor that may be hotspots for diverse deep-sea organisms that we know little about."<br /> <br /> Because the techniques used by the researchers can be modified to investigate other seafloor features, this approach -- as well as the conclusion that there is an apparent "symbiosis" between deep-sea fauna and the nodules -- could also have implications for future biodiversity research.<br /> <br /> "Vast regions of the deep sea are unexplored," Dr. Dutkiewicz said, "so the consequences of nodule mining for deep-sea ecosystems need to be carefully evaluated."</div> <br /> <br /> <u><i><span style="font-family: "trebuchet ms" , sans-serif;">The above story is based on <a href="https://www.geosociety.org/GSA/News/pr/2020/20-02.aspx" rel="nofollow" target="_blank">Materials</a> provided by <a href="http://www.geosociety.org/" rel="nofollow" target="_blank">Geological Society of America</a>.</span></i></u></div>

How Nodules Stay on Top at the Bottom of the Sea

Photo credit: Utah Geological Survey Rare metallic elements found in clumps on the deep-ocean floor mysteriously remain uncovered de...

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7 Billion-Year-Old Stardust Is Oldest Material Found on Earth

<div dir="ltr" style="text-align: left;" trbidi="on"> <div class="separator" style="clear: both; text-align: center;"> <a href="https://1.bp.blogspot.com/-M3vhjfvCNqE/Xh0fy4OlXbI/AAAAAAAARzc/usz34MYZpfg3ozdozbowB7DPDL4o0xxYACLcBGAsYHQ/s1600/7%2BBillion-Year-Old%2BStardust%2BIs%2BOldest%2BMaterial%2BFound%2Bon%2BEarth%2B%25281%2529.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="630" data-original-width="1200" height="336" src="https://1.bp.blogspot.com/-M3vhjfvCNqE/Xh0fy4OlXbI/AAAAAAAARzc/usz34MYZpfg3ozdozbowB7DPDL4o0xxYACLcBGAsYHQ/s640/7%2BBillion-Year-Old%2BStardust%2BIs%2BOldest%2BMaterial%2BFound%2Bon%2BEarth%2B%25281%2529.jpg" width="640" /></a></div> <br /> <br /> <br /> <span style="font-family: "georgia" , "times new roman" , serif;">Scientists recently identified the oldest material on Earth: stardust that's 7 billion years old, tucked away in a massive, rocky meteorite that struck our planet half a century ago. </span><br /> <br /> Stars have life cycles. They're born when bits of dust and gas floating through space find each other and collapse in on each other and heat up. They burn for millions to billions of years, and then they die. When they die, they pitch the particles that formed in their winds out into space, and those bits of stardust eventually form new stars, along with new planets and moons and meteorites. And in a meteorite that fell fifty years ago in Australia, scientists have now discovered stardust that formed 5 to 7 billion years ago -- the oldest solid material ever found on Earth.<br /> <br /> "This is one of the most exciting studies I've worked on," says Philipp Heck, a curator at the Field Museum, associate professor at the University of Chicago, and lead author of a paper describing the findings in the Proceedings of the National Academy of Sciences. "These are the oldest solid materials ever found, and they tell us about how stars formed in our galaxy."<br /> <br /> The materials Heck and his colleagues examined are called presolar grains-minerals formed before the Sun was born. "They're solid samples of stars, real stardust," says Heck. These bits of stardust became trapped in meteorites where they remained unchanged for billions of years, making them time capsules of the time before the solar system..<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> But presolar grains are hard to come by. They're rare, found only in about five percent of meteorites that have fallen to Earth, and they're tiny-a hundred of the biggest ones would fit on the period at the end of this sentence.<br /> <br /> But the Field Museum has the largest portion of the Murchison meteorite, a treasure trove of presolar grains that fell in Australia in 1969 and that the people of Murchison, Victoria, made available to science. Presolar grains for this study were isolated from the Murchison meteorite for this study about 30 years ago at the University of Chicago.<br /> <br /> "It starts with crushing fragments of the meteorite down into a powder ," explains Jennika Greer, a graduate student at the Field Museum and the University of Chicago and co-author of the study. "Once all the pieces are segregated, it's a kind of paste, and it has a pungent characteristic-it smells like rotten peanut butter."<br /> <br /> This "rotten-peanut-butter-meteorite paste" was then dissolved with acid, until only the presolar grains remained. "It's like burning down the haystack to find the needle," says Heck.<br /> <br /> Once the presolar grains were isolated, the researchers figured out from what types of stars they came and how old they were. "We used exposure age data, which basically measures their exposure to cosmic rays, which are high-energy particles that fly through our galaxy and penetrate solid matter," explains Heck. "Some of these cosmic rays interact with the matter and form new elements. And the longer they get exposed, the more those elements form.<br /> <br /> "I compare this with putting out a bucket in a rainstorm. Assuming the rainfall is constant, the amount of water that accumulates in the bucket tells you how long it was exposed," he adds. By measuring how many of these new cosmic-ray produced elements are present in a presolar grain, we can tell how long it was exposed to cosmic rays, which tells us how old it is.<br /> <br /> The researchers learned that some of the presolar grains in their sample were the oldest ever discovered-based on how many cosmic rays they'd soaked up, most of the grains had to be 4.6 to 4.9 billion years old, and some grains were even older than 5.5 billion years. For context, our Sun is 4.6 billion years old, and Earth is 4.5 billion.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> But the age of the presolar grains wasn't the end of the discovery. Since presolar grains are formed when a star dies, they can tell us about the history of stars. And 7 billion years ago, there was apparently a bumper crop of new stars forming-a sort of astral baby boom.<br /> <br /> "We have more young grains that we expected," says Heck. "Our hypothesis is that the majority of those grains, which are 4.9 to 4.6 billion years old, formed in an episode of enhanced star formation. There was a time before the start of the Solar System when more stars formed than normal."<br /> <br /> This finding is ammo in a debate between scientists about whether or not new stars form at a steady rate, or if there are highs and lows in the number of new stars over time. "Some people think that the star formation rate of the galaxy is constant," says Heck. "But thanks to these grains, we now have direct evidence for a period of enhanced star formation in our galaxy seven billion years ago with samples from meteorites. This is one of the key findings of our study."<br /> <br /> Heck notes that this isn't the only unexpected thing his team found. As almost a side note to the main research questions, in examining the way that the minerals in the grains interacted with cosmic rays, the researchers also learned that presolar grains often float through space stuck together in large clusters, "like granola," says Heck. "No one thought this was possible at that scale."<br /> <br /> Heck and his colleagues look forward to all of these discoveries furthering our knowledge of our galaxy. "With this study, we have directly determined the lifetimes of stardust. We hope this will be picked up and studied so that people can use this as input for models of the whole galactic life cycle," he says.<br /> <br /> Heck notes that there are lifetimes' worth of questions left to answer about presolar grains and the early Solar System. "I wish we had more people working on it to learn more about our home galaxy, the Milky Way," he says.<br /> <br /> "Once learning about this, how do you want to study anything else?" says Greer. "It's awesome, it's the most interesting thing in the world."<br /> <br /> "I always wanted to do astronomy with geological samples I can hold in my hand," says Heck. "It's so exciting to look at the history of our galaxy. Stardust is the oldest material to reach Earth, and from it, we can learn about our parent stars, the origin of the carbon in our bodies, the origin of the oxygen we breathe. With stardust, we can trace that material back to the time before the Sun."<br /> <br /> "It's the next best thing to being able to take a sample directly from a star," says Greer.<br /> <br /> This study was contributed to by researchers from the Field Museum, University of Chicago, Lawrence Livermore National Laboratory, Washington University, Harvard Medical School, ETH Zurich, and the Australian National University. Funding was provided by NASA, the TAWANI Foundation, the National Science Foundation, the Department of Energy, the Swiss National Science Foundation, the Brazilian National Council for Scientific and Technological Development and the Field Museum's Science and Scholarship Funding Committee.<br /> <br /> <br /> <u><i><span style="font-family: "trebuchet ms" , sans-serif;">The above story is based on <a href="https://www.fieldmuseum.org/about/press/meteorite-contains-oldest-material-earth-7-billion-year-old-stardust" rel="nofollow" target="_blank">Materials</a> provided by <a href="https://www.fieldmuseum.org/" rel="nofollow" target="_blank">Field Museum</a>.</span></i></u></div>

7 Billion-Year-Old Stardust Is Oldest Material Found on Earth

Scientists recently identified the oldest material on Earth: stardust that's 7 billion years old, tucked away in a massive, rocky ...

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Scientists Catch a Volcano Mid-formation in the Indian Ocean

<div dir="ltr" style="text-align: left;" trbidi="on"> <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody> <tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-x6WprxkIMlk/XhYGhjerY2I/AAAAAAAARzE/3Of1yfeho3gDNpXyYsaaJUVaBQQx6gexgCLcBGAsYHQ/s1600/Scientists%2BCatch%2Ba%2BVolcano%2BMid-formation%2Bin%2Bthe%2BIndian%2BOcean%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Scientists Catch a Volcano Mid-formation in the Indian Ocean" border="0" data-original-height="1049" data-original-width="1216" height="552" src="https://1.bp.blogspot.com/-x6WprxkIMlk/XhYGhjerY2I/AAAAAAAARzE/3Of1yfeho3gDNpXyYsaaJUVaBQQx6gexgCLcBGAsYHQ/s640/Scientists%2BCatch%2Ba%2BVolcano%2BMid-formation%2Bin%2Bthe%2BIndian%2BOcean%2B%25281%2529.jpg" title="" width="640" /></a></td></tr> <tr><td class="tr-caption" style="text-align: center;">This illustration shows how magma in a reservoir deep underground ascended to form a submarine volcano in the Indian Ocean.  (Image credit: James Tuttle Keane/Nature Geoscience (2020))</td></tr> </tbody></table> <br /> <span style="font-family: "georgia" , "times new roman" , serif;">Mysterious seismic hums detected around the world were likely caused by an unusual geologic event — the rumblings of a magma-filled reservoir deep under the Indian Ocean, a new study finds. </span><br /> <br /> These odd hums were an unconventional geologic birth announcement. A few months after the sounds rippled around the Earth, a new underwater volcano was born off the coast of the island of Mayotte, located between Madagascar and Mozambique in the Indian Ocean.<br /> <br /> Since May 2018, an unusual sequence of earthquakes has been recorded off the coast of the island of Mayotte in the Comoros archipelago between Africa and Madagascar. Seismic activity began with a swarm of thousands of "seemingly tectonic" earthquakes, culminating in an earthquake of magnitude 5.9 in May 2018. Mostly, since June 2018, however, a completely new form of earthquake signal has emerged that was so strong that it could be recorded up to 1000 kilometers away. <br /> <br /> These 20- to 30-minute-long signals are characterized by particularly harmonic, low frequencies, almost monochromatic, similar to a large bell or a double bass, and are called very long period (VLP) signals. Although the centre of the seismic activity was located almost 35 kilometers offshore the east of the island, a continuous lowering and eastward motion of the Earth's surface at Mayotte had begun at the same time as the massive swarms of VLP events started, accumulating to almost 20 cm to date.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> Although there was no evidence of earlier volcanic activity in the epicenter of the seismic activity, GFZ scientists had suspected magmatic processes from the beginning—quake swarms in the upper crust that often arise as a reaction to the rise of magma and VLPs in earlier years were associated with the collapse of large caldera volcanoes.<br /> <br /> The special frequency content of the VLP signals is caused by the resonance oscillation of the buried magma chamber. The deeper the vibrations, the larger the magma reservoir. However, the earthquake swarms under the ocean floor were much deeper than with other volcanoes and the resonance tones of the VLPs were unusually low and strong.<br /> <br /> An international team led by GFZ scientist Simone Cesca analyzed seismological and geodetic data from the region to study these observations and their evolution over time. However, the investigations were complicated by the fact that there was no seismic network on the ocean floor, and therefore, measurements were only available at great distances on Mayotte, Madagascar and in Africa. "We tried to improve the unfavorable initial situation by developing special new analytical methods such as cluster and directional beam methods," says Cesca.<br /> <br /> The team identified different activity phases within the sequence of events from May 2018 to today. The initial swarm phase indicated a rapid upward movement of magma from a deep mantle reservoir more than 30 kilometers below the Earth's surface. Once an open channel had formed from the Earth's mantle to the seabed, the magma began to flow unhindered and form a new underwater volcano. A French oceanographic campaign recently confirmed the birth of the submarine volcano, whose location coincides with the reconstructed magma rise.<br /> <br /> In this phase, the apparent tectonic earthquake activity decreased again, while the lowering of the ground on the island of Mayotte began. Likewise, long-lasting monofreququent VLP signals started. "We interpret this as a sign of the collapse of the deep magma chamber off the coast of Mayotte," explains Eleonora Rivalta, co-author of the scientific team. "It is the deepest (~30 km) and largest magma reservoir in the upper mantle (more than 3.4 cubic kilometers) to date, which is beginning to empty abruptly.<br /> <br /> "Since the seabed lies 3 kilometers below the water surface, almost nobody noticed the enormous eruption. However, there are still possible hazards for the island of Mayotte today, as the Earth's crust above the deep reservoir could continue to collapse, triggering stronger earthquakes," says Torsten Dahm, head of the section Physics of Earthquakes and Volcanoes at the GFZ.<br /> <br /> In all, about 0.4 cubic miles (1.5 cubic km) of magma drained out of the reservoir, the researchers calculated. However, given the vast size of the volcano, it's likely that even more magma was involved, Cesca noted.<br /> <br /> Although the volcano is now formed, earthquakes may still rattle the area.<br /> <br /> "There are still possible hazards for the island of Mayotte today," study senior researcher and head of the section Physics of Earthquakes and Volcanoes at the GFZ Torsten Dahm, said in a statement "The Earth's crust above the deep reservoir could continue to collapse, triggering stronger earthquakes."<br /> <span style="font-family: "georgia" , "times new roman" , serif;"> <br /> <br /> <br /> <u><i><span style="font-family: "trebuchet ms" , sans-serif;">The above story is based on <a href="http://dx.doi.org/10.1038/s41561-019-0505-5" rel="nofollow" target="_blank">materials </a>provided by <a href="https://www.helmholtz.de/en/" rel="nofollow" target="_blank">Helmholtz Association of German Research Centres.</a></span></i></u></span></div>

Scientists Catch a Volcano Mid-formation in the Indian Ocean

This illustration shows how magma in a reservoir deep underground ascended to form a submarine volcano in the Indian Ocean.  (Image credi...

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Crater From Asteroid Impact That Covered 10% of Earth's Surface in Debris

<div dir="ltr" style="text-align: left;" trbidi="on"> <div class="separator" style="clear: both; text-align: center;"> <a href="https://1.bp.blogspot.com/-0cE9ORW9uXE/XhSvwQMXB2I/AAAAAAAARyo/HoSQp-ox6sAIx7CDGZmFhYTa_d-GGcFqACLcBGAsYHQ/s1600/Crater%2BFrom%2BAsteroid%2BImpact%2BThat%2BCovered%2B10%2525%2Bof%2BEarth%2527s%2BSurface%2Bin%2BDebris.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="Crater From Asteroid Impact That Covered 10% of Earth's Surface in Debris" border="0" data-original-height="574" data-original-width="1153" height="318" src="https://1.bp.blogspot.com/-0cE9ORW9uXE/XhSvwQMXB2I/AAAAAAAARyo/HoSQp-ox6sAIx7CDGZmFhYTa_d-GGcFqACLcBGAsYHQ/s640/Crater%2BFrom%2BAsteroid%2BImpact%2BThat%2BCovered%2B10%2525%2Bof%2BEarth%2527s%2BSurface%2Bin%2BDebris.jpg" title="" width="640" /></a></div> <br /> <br /> A flash of light would have come first, followed by a shockwave and massive earthquake. Only later would the hailstorm of black, glassy debris begun to fall, a rocky rain that would touch 10 percent of the planet's surface.<br /> <br /> A team of researchers with members from Singapore, the U.S., Thailand and Laos has concluded that the impact point of a meteorite that struck the Earth approximately 790,000 years ago lies buried beneath a volcanic field in southern Laos. In their paper published in Proceedings of the National Academy of Sciences, the group outlines four lines of evidence that point to the Bolaven volcanic field as the likely site of the meteorite strike.<br /> <br /> Prior research has shown that approximately 790,000 years ago, a large meteorite (the largest known young meteorite impact) struck Earth in the Eastern Hemisphere. So great was the impact that debris was strewn across a tenth of the entire planet's surface.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> Scientists know about the impact because of bits of glassy clasts known as tektites have been found in places like Antarctica, Australia and Southeast Asia. <br /> <br /> Prior evidence also suggested the impact site was likely somewhere in Southeast Asia, but until now, the exact location has been unknown. In this new effort, the researchers have found evidence that suggests the reason the crater has not been found is that it is hidden beneath a volcanic field—and they provide four lines of evidence to back up their claim.<br /> <br /> The first line of evidence involved the geochemistry of the tektites in the vicinity of the Bolaven volcanic field—the researchers claim it implies the presence of basalts at the impact site. The second line involved geologic mapping and dating of basaltic lavas that existed before and after the time of the impact, which showed a change occurred around the time of the impact. The fourth line of evidence came from gravity measurements the team took at the Bolaven volcanic field—they report an anomaly that suggests the presence of a 13- to 17-kilometer crater. <br /> <br /> The final piece of evidence came from what the team describes as an outcrop of crudely layered sandstone and mudstone boulders 10 to 20 kilometers from the Bolaven volcanic field, which appear to have been thrown there by the force of the meteorite striking the ground.<br /> <br /> The researchers suggest that taken together, their four lines of evidence very strongly suggest that the impact site for the ancient meteorite was the Bolaven volcanic field.<br /> <br /> <br /> <br /> <u><i><span style="font-family: "trebuchet ms" , sans-serif;">The above story is based on <a href="https://www.pnas.org/content/early/2019/12/24/1904368116" rel="nofollow" target="_blank">materials </a>provided by <a href="https://www.pnas.org/" rel="nofollow" target="_blank">Proceedings of the National Academy of Sciences.</a></span></i></u></div>

Crater From Asteroid Impact That Covered 10% of Earth's Surface in Debris

A flash of light would have come first, followed by a shockwave and massive earthquake. Only later would the hailstorm of black, glassy...

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What is Fire Opal?

<div dir="ltr" style="text-align: left;" trbidi="on"> <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody> <tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-NpJg2xeNv3k/XhNr0mIYJuI/AAAAAAAARyc/P5noG4MXNOkO_r0k2ZyG1trTScJSDYF_ACLcBGAsYHQ/s1600/Fire%2BOpal.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Fire Opal" border="0" data-original-height="1014" data-original-width="1352" height="480" src="https://1.bp.blogspot.com/-NpJg2xeNv3k/XhNr0mIYJuI/AAAAAAAARyc/P5noG4MXNOkO_r0k2ZyG1trTScJSDYF_ACLcBGAsYHQ/s640/Fire%2BOpal.jpg" title="" width="640" /></a></td></tr> <tr><td class="tr-caption" style="text-align: center;">Stunning Mexican Fire Opal. Photo: Jeff Schultz</td></tr> </tbody></table> <br /> <br /> <b>Fire opal</b> is a transparent to translucent opal, with warm body colors of yellow to orange to red. Although it does not usually show any play of color, occasionally a stone will exhibit bright green flashes. <br /> <br /> Like other opals, fire opal is <b>amorphous </b>hydrated silicon dioxide by chemical composition. "Amorphous" indicates that opal has no crystalline structure; "hydrated" means that it contains water, typically from 3 to 10%. Opal is actually considered to be a kind of hardened jelly. But fire opal has some unusual characteristics not shared by other opals.<br /> <br /> Fire opal glows with the <b>fire of the sun</b>: hot honey yellows, oranges, and reds so bright they look as though they might glow in the dark. Fire opal sometimes only occasionally exhibits an opalescence or play of color like other opals but it does not need this to take a starring role in jewelry. Its juicy color is just the right accent to earth tones or black and also looks great paired with other bright tones.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> Fire opals that do not show play of color are sometimes referred to as jelly opals. <br /> <br /> Fire opal is associated particularly with Mexico, and is mined in the Mexican states of Queretaro, Hidalgo, Guerrero, Michoacan, Julisio, Chihuahua and San Luis Potosi. The most important mines in Queretaro were discovered in 1835 and are still producing today. Small quantities of fire opal can also be found in Oregon in the USA and British Columbia in Canada.<br /> <br /> Mexican opals are sometimes cut in their ryholitic host material if it is hard enough to allow cutting and polishing. This type of Mexican opal is referred to as a Cantera opal. Also, a type of opal from Mexico, referred to as Mexican water opal, is a colorless opal which exhibits either a bluish or golden internal sheen.<br /> <br /> Unlike most opal, fire opal is sometimes <b>faceted</b>, so you can choose sparkle as well as color. Because it is light as well as bright, fire opal is especially good for earrings, where even small sizes have a big punch of color.  Only the very finest qualities of Fire Opal are suitable for faceting. <br /> <br /> Since fire opal has a high <b>water content</b>, it should be protected from heat and prolonged exposure to strong light, which could dry it out. Lapidaries cure fire opal by drying it before cutting to reduce instability, so it is actually not that delicate. But due to its relative softness, it is best suited for pendants, earrings, not everyday rings.<br /> <h4 style="text-align: left;"> <span style="color: blue;"><span style="font-family: "georgia" , "times new roman" , serif;">Video:  </span></span></h4> <div class="facebook-responsive"> <iframe allowfullscreen="true" allowtransparency="true" frameborder="0" height="315" scrolling="no" src="https://www.facebook.com/plugins/video.php?href=https%3A%2F%2Fwww.facebook.com%2FAmazingGeologist%2Fvideos%2F437730813474227%2F&show_text=0&width=560" style="border: none; overflow: hidden;" width="560"></iframe><br /></div> <b><span style="font-family: "georgia" , "times new roman" , serif;">See also: </span></b><br /> <span style="font-family: "georgia" , "times new roman" , serif;"><a href="https://www.geologyin.com/2017/12/how-does-opal-get-its-color.html" target="_blank">How Does Opal Get Its Color?</a></span><br /> <span style="font-family: "georgia" , "times new roman" , serif;"><a href="https://www.geologyin.com/2016/06/types-of-opal-with-photos.html" target="_blank">Types of Opal With Photos </a></span><br /> <span style="font-family: "georgia" , "times new roman" , serif;"><span style="font-family: "georgia" , "times new roman" , serif;"><a href="https://www.geologyin.com/2019/07/what-is-crazy-lace-agate.html" target="_blank">What is Crazy Lace Agate? </a></span></span></div>

What is Fire Opal?

Stunning Mexican Fire Opal. Photo: Jeff Schultz Fire opal is a transparent to translucent opal, with warm body colors of yellow to o...

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What is the Lifespan of Volcanic Islands Like Hawaii?

<div dir="ltr" style="text-align: left;" trbidi="on"> <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody> <tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-IZXocqB5qAQ/XhDEalMkGNI/AAAAAAAARyQ/socyOlzA4m8Eeh4aYVmpzqRRc659P-jYgCLcBGAsYHQ/s1600/What%2Bis%2Bthe%2BLifespan%2Bof%2BVolcanic%2BIslands%2BLike%2BHawai.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="765" data-original-width="1147" height="265" src="https://1.bp.blogspot.com/-IZXocqB5qAQ/XhDEalMkGNI/AAAAAAAARyQ/socyOlzA4m8Eeh4aYVmpzqRRc659P-jYgCLcBGAsYHQ/s400/What%2Bis%2Bthe%2BLifespan%2Bof%2BVolcanic%2BIslands%2BLike%2BHawai.jpg" width="400" /></a></td></tr> <tr><td class="tr-caption" style="text-align: center;">Nishinoshima island</td></tr> </tbody></table> <br /> <div style="text-align: left;"> When a hot plume of rock rises through the Earth's mantle to puncture the overlying crust, it can create not only a volcanic ocean island, but also a swell in the ocean floor hundreds to thousands of kilometers long. Over time the island is carried away by the underlying tectonic plate, and the plume pops out another island in its place. Over millions of years, this geological hotspot can produce a chain of trailing islands, on which life may flourish temporarily before the islands sink, one by one, back into the sea.<br /> <br /> The Earth is pocked with dozens of hotspots, including those that produced the island chains of Hawaii and the Galapagos. While the process by which volcanic islands form is similar from chain to chain, the time that any island spends above sea level can vary widely, from a few million years in the case of the Galapagos to over 20 million for the Canary Islands. An island's age can determine the life and landscapes that evolve there. And yet the mechanisms that set an island's lifespan are largely unknown.<br /> <br /> Now scientists at MIT have an idea about the processes that determine a volcanic island's age. In a paper published today in Science Advances, they report an analysis of 14 major volcanic island chains around the world. They found that an island's age is related to two main geological factors: the speed of the underlying plate and the size of the swell generated by the hotspot plume.<br /> <br /> For instance, if an island lies on a fast-moving plate, it is likely to have a short lifespan, unless, as is the case with Hawaii, it was also created by a very large plume. The plume that gave rise to the Hawaiian islands is among the largest on Earth, and while the Pacific plate on which Hawaii sits is relatively speedy compared with other oceanic plates, it takes considerable time for the plate to slide over the plume's expansive swell.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> The researchers found that this interplay between tectonic speed and plume size explains why the Hawaiian islands persist above sea level for million years longer than the oldest Galapagos Islands, which also sit on plates that travel at a similar speed but over a much smaller plume. By comparison, the Canary Islands, among the oldest island chains in the world, sit on the slow-moving Atlantic plate and over a relatively large plume.<br /> <br /> "These island chains are dynamic, insular laboratories that biologists have long focused on," says former MIT graduate student Kimberly Huppert, the study's lead author. "But besides studies on individual chains, there's not a lot of work that related them to processes of the solid Earth, kilometers below the surface."<br /> <br /> "You can imagine all these organisms living on a sort of treadmill made of islands, like stepping stones, and they're evolving, diverging, migrating to new islands, and the old islands are drowning," adds Taylor Perron, associate head of MIT's Department of Earth, Atmospheric and Planetary Sciences. "What Kim has shown is, there's a geophysical mechanism that controls how fast this treadmill is moving and how long the island chains go before they drop off the end."<br /> <br /> Huppert and Perron co-authored the study with Leigh Royden, professor of earth, atmospheric and planetary sciences at MIT.</div> <h4> <span style="font-family: "georgia" , "times new roman" , serif;">Sinking a blowtorch</span></h4> <div style="text-align: left;"> The new study is a part of Huppert's MIT thesis work, in which she looked mainly at the evolution of landscapes on volcanic island chains, the Hawaiian islands in particular. In studying the processes that contribute to island erosion, she dug up a controversy in the literature regarding the processes that cause the seafloor to swell around hotspot islands.<br /> <br /> "The idea was, if you heat some of the bottom of the plate, you can make it go up really fast by just thermal uplift, basically like a blowtorch under the plate," Royden says.<br /> <br /> If this idea is correct, then by the same token, cooling of the heated plate should cause the seafloor to subside and islands to eventually sink back into the ocean. But in studying the ages of drowned islands in hotspot chains around the world, Huppert found that islands drown at a faster rate than any natural cooling mechanism could explain.<br /> <br /> "So most of this uplift and sinking couldn't have been from heating and cooling," Royden says. "It had to be something else."<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> Huppert's observation inspired the group to compare major volcanic island chains in hopes of identifying the mechanisms of island uplift and sinking—which are likely the same processes that set an island's lifespan, or time above sea level.</div> <h4 style="text-align: left;"> <span style="font-family: "georgia" , "times new roman" , serif;">Evolution, on a treadmill</span></h4> <div style="text-align: left;"> In their analysis, the researchers looked at 14 volcanic island chains around the world, including the Hawaiian, Galapagos, and Canary islands. For each island chain, they noted the direction in which the underlying tectonic plate was moving and measured the plate's average speed relative to the hotspot. They then measured, in the direction of each island chain, the distance between the beginning and the end of the swell, or uplift in the crust, created by the underlying plume.<br /> <br /> For every island chain, they divided the swell distance by plate velocity to arrive at a number representing the average time a volcanic island should spend atop the plume's swell—which should determine how long an island remains above sea level before sinking into the ocean.<br /> <br /> When the researchers compared their calculations with the actual ages of each island in each of the 14 chains, including islands that had long since sunk below sea level, they found a strong correlation between the time spent atop the swell and the typical amount of time that islands remain above sea level. A volcanic island's lifespan, they concluded, depends on a combination of the underlying plate's speed and the size of the plume, or swell that it creates.<br /> <br /> Huppert says that the processes that set an island's age can help scientists better understand biodiversity and how life looks different from one island chain to another.<br /> <br /> "If an island spends a long time above sea level, that provides a long time for speciation to play out," Huppert says. "But if you have an island chain where you have islands that drown at a faster rate, then it will affect the ability of fauna to radiate to neighboring islands, and how these islands are populated."<br /> <br /> The researchers posit that, in some sense, we have the interplay of tectonic speed and plume size to thank for our modern understanding of evolution.<br /> <br /> "You're looking at a process in the solid Earth which is contributing to the fact that the Galapagos is a very fast moving treadmill, with islands moving off very quickly, with not a long time to erode, and this was the system that led to people discovering evolution," Royden notes. "So in a sense this process really set the stage for humans to figure out what evolution was about, by doing it in this microcosm. If there hadn't been this process, and the Galapagos hadn't been on that short residence time, who knows how long it would have taken for people to figure it out."<br /> <br /> <br /> <u><i><span style="font-family: "trebuchet ms" , sans-serif;">The above story is based on <a href="https://advances.sciencemag.org/content/6/1/eaaw6906" rel="nofollow" target="_blank">materials </a>provided by <a href="http://www.mit.edu/" rel="nofollow" target="_blank">MIT</a>.</span></i></u></div> </div>

What is the Lifespan of Volcanic Islands Like Hawaii?

Nishinoshima island When a hot plume of rock rises through the Earth's mantle to puncture the overlying crust, it can create not ...

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Imperfect Diamonds Paved Road to Historic Deep Earth Discoveries

<div dir="ltr" style="text-align: left;" trbidi="on"> <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody> <tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-bxU1gasOwek/Xgoiv5SzTtI/AAAAAAAARyE/FruGE6GBO9oGmdcHSV6jkxUbFLzMwxetgCLcBGAsYHQ/s1600/31%2BNew%2BCarbon-Bearing%2BMinerals%2BFound%2Bin%2BFour%2BYears%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1207" data-original-width="1440" height="536" src="https://1.bp.blogspot.com/-bxU1gasOwek/Xgoiv5SzTtI/AAAAAAAARyE/FruGE6GBO9oGmdcHSV6jkxUbFLzMwxetgCLcBGAsYHQ/s640/31%2BNew%2BCarbon-Bearing%2BMinerals%2BFound%2Bin%2BFour%2BYears%2B%25281%2529.jpg" width="640" /></a></td></tr> <tr><td class="tr-caption" style="text-align: center;"> 31 new-to-science minerals have turned up (including triazolite, discovered in Chile, thought to have derived in part from cormorant guano. Photo: Joy Desor, Mineralanalytik Analytical Services</td></tr> </tbody></table> <br /> <div style="text-align: left;"> Thousands of diamonds, formed hundreds of kilometers deep inside the planet, paved the road to some of the 10-year Deep Carbon Observatory program's most historic accomplishments and discoveries, being celebrated at the US National Academy of Sciences.<br /> <br /> Unsightly black, red, green, and brown specks of minerals, and microscopic pockets of fluid and gas encapsulated by diamonds as they form in Deep Earth, record the elemental surroundings and reactions taking place within Earth at a specific depth and time, divulging some of the planet's innermost secrets.<br /> <br /> Hydrogen and oxygen, for example, trapped inside diamonds from a layer 410 to 660 kilometers below Earth's surface, reveal the subterranean existence of oceans' worth of H₂O -- far more in mass than all the water in every ocean in the surface world.<br /> <br /> This massive amount of water may have been brought to Deep Earth from the surface by the movement of the great continental and oceanic plates which, as they separate and move, collide with one another and overlap. This subduction of slabs also buries carbon from the surface back into the depths, a process fundamental to Earth's natural carbon balance, and therefore to life.<br /> <br /> Knowledge of Deep Earth's water content is critical to understanding the diversity and melting behaviors of materials at the planet's different depths, the creation and flows of hydrocarbons (e.g. petroleum and natural gas) and other materials, as well as the planet's deep subterranean electrical conductivity.<br /> <br /> By dating the pristine fragments of material trapped inside other super-deep diamond "inclusions," DCO researchers could put an approximate time stamp on the start of plate tectonics -- "one of the planet's greatest innovations," in the words of DCO Executive Director Robert Hazen of the Carnegie Institution for Science. It started roughly 3 billion years ago, when the Earth was a mere 1.5 billion years old.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> Diamond research accelerated dramatically thanks to the creation of DCO's global network of researchers and led to some of the program's most intriguing discoveries and achievements.<br /> <br /> Diamonds from the deepest depths, often small with poor clarity, are not generally used as gemstones by Tiffany's but are amazingly complex, robust and priceless in research. Inclusions offered DCO scientists samples of minerals that exist only at extreme high subterranean pressure, and suggested three ways in which diamonds form.<br /> <br /> While as many as 90% of analyzed diamonds were composed of carbon scientists expected in the mantle, some "relatively young" diamonds (up to a few hundred million years old) appear to include carbon from once-living sources; in other words, they are made of carbon returned to Deep Earth from the surface world.<br /> <br /> Diamonds also revealed unambiguous evidence that some hydrocarbons form hundreds of miles down, well beyond the realm of living cells: abiotic energy.<br /> <br /> Unravelling the mystery of deep abiotic methane and other energy sources helps explain how deep life in the form of microbes and bacteria is nourished, and fuels the proposition that life first originated and evolved far below (rather than migrating down from) the surface world.<br /> <br /> Diamonds also enabled DCO scientists to simulate the extreme conditions of Earth's interior.<br /> <br /> DCO's Extreme Physics and Chemistry community scientists used diamond anvil cells -- a tool that can squeeze a sample tremendously between the tips of two diamonds, coupled with lasers that heat the compressed crystals -- to simulate deep Earth's almost unimaginable extreme temperatures and pressures.<br /> <br /> Using a variety of advanced techniques, they analyzed the compressed samples, identified 100 new carbon-bearing crystal structures and documented their intriguing properties and behaviors.<br /> <br /> The work provided insights into how carbon atoms in Deep Earth "find one another," aggregate, and assemble to form diamonds and other material.</div> <h4 style="text-align: left;"> <b><span style="font-family: "georgia" , "times new roman" , serif;">Development of new materials; potential carbon capture and storage strategies</span></b></h4> <div style="text-align: left;"> DCO's discoveries and research are important and applicable in many ways, including the development of new materials and potential carbon capture and storage strategies.<br /> <br /> DCO scientists are studying, for example, how the natural timescale for sequestration of carbon might be shortened.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> The weathering of and microbial life inside Oman's Samail Ophiolite -- an unusual, large slab pushed up from Earth's upper mantle long ago -- offers a tutorial in nature's carbon sequestration techniques, knowledge that might help offset carbon emissions caused by humans.<br /> <br /> In Iceland, another DCO natural sequestration project, CarbFix, involves injecting carbon-bearing fluids into basalt and observing their conversion to solids.</div> <h4 style="text-align: left;"> <span style="font-family: "georgia" , "times new roman" , serif;">A Decade of Discovery</span></h4> <div style="text-align: left;"> Hundreds of scientists from around the world meet in Washington DC to share and celebrate results of the wide-ranging, decade-long Deep Carbon Observatory -- one of the largest global research collaborations in Earth sciences ever undertaken.<br /> <br /> With its Secretariat at the Carnegie Institution for Science in Washington DC, and $50 million in core support from the Alfred P. Sloan Foundation, multiplied many times by additional investment worldwide, a multidisciplinary group of 1,200 researchers from 55 nations worked for 10 years in four interconnected scientic "communities" to explore Earth's fundamental workings, including:</div> <ul style="text-align: left;"> <li>How carbon moves between Earth's interior, surface and atmosphere</li> <li>Where Earth's deep carbon came from, how much exists and in what forms</li> <li>How life began, and the limits -- such as temperature and pressure -- to Earth's deep microbial life</li> </ul> <div style="text-align: left;"> They met the challenge of investigating Earth's interior in several ways, producing 1,400 peer-reviewed papers while pursuing 268 projects that involved, for example:</div> <ul style="text-align: left;"> <li>Studying diamonds, volcanoes, and core samples obtained by drilling on land and at sea</li> <li>Conducting lab experiments to mimic the extreme temperatures and pressures of Earth's interior, and through theoretical modeling of carbon's evolution and movements over deep time, and</li> <li>Developing new high tech instruments</li> <li>DCO scientists conducted field measurements in remote and inhospitable regions of the world: ocean floors, on top of active volcanoes, and in the deserts of the Middle East.</li> </ul> <div style="text-align: left;"> <br /> Where instrumentation and models were lacking, DCO scientists developed new tools and models to meet the challenge. Throughout these studies, DCO invested in the next generation of deep carbon researchers, students and early career scientists, who will carry on the tradition of exploration and discovery for decades to come.</div> <h4 style="text-align: left;"> <span style="font-family: "georgia" , "times new roman" , serif;">Key discoveries during the 10-year Deep Carbon Observatory program</span></h4> <div style="text-align: left;"> In addition to insights from its diamond research above, the program's top discoveries include:<br /> <br /> <b><span style="font-family: "georgia" , "times new roman" , serif;">The deep biosphere is one of Earth's largest ecosystems</span></b><br /> <br /> Life in the deep subsurface totals 15,000 to 23,000 megatonnes (million metric tons) of carbon, about 250 to 400 times greater than the carbon mass of all humans. The immense Deep Earth biosphere occupies a space nearly twice as large as all the world's oceans.<br /> <br /> DCO scientists explored how microbes draw sustenance from "abiotic" methane and other energy sources -- fuel that wasn't derived from biotic life above.<br /> <br /> If microbes can eek out a living using chemical energy from rocks in Earth's deep subsurface, that may hold true on other planetary bodies.<br /> <br /> This knowledge about the types of environments that can sustain life, particularly those where energy is limited, can guide the search for life on other planets. In the outer solar system, for example, energy from the sun is scarce, as it is in Earth's subsurface environment.<br /> <br /> DCO researchers also found the deepest, lowest-density, and longest-lived subseafloor microbial ecosystem ever recorded and changed our understanding of the limits of life at extremes of pressure, temperature, and depth.<br /> <br /> <b>Rocks and fluids in Earth's crust provide clues to the origins of life on this planet, and where to look for life on others</b><br /> <br /> DCO scientists found amino acids and complex organic molecules in rocks on the seafloor. These molecules, the building blocks of life, were formed by abiotic synthesis and had never before been observed in the geologic record.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> They also found pockets of ancient salty fluids rich in hydrogen, methane, and helium many kilometers deep, providing evidence of early, protected environments capable of harboring life.<br /> <br /> <b>Abiotic methane forms in the crust and mantle of Earth</b><br /> <br /> When water meets the ubiquitous mineral olivine under pressure, the rock reacts with oxygen atoms from the H₂O and transforms into another mineral, serpentine -- characterized by a scaly, green-brown, snake skin-like appearance.<br /> <br /> This process of "serpentinization" leads to the formation of "abiotic" methane in many different environments on Earth. DCO scientists developed and used sophisticated analytical equipment to differentiate between biotic (derived from ancient plants and animals) and abiotic formation of methane.<br /> <br /> DCO field and laboratory studies of rocks from the upper mantle document a new high-pressure serpentinization process that produces abiotic methane and other forms of hydrocarbons.<br /> <br /> The formation of methane and hydrocarbons through these geologic, abiotic processes provides fuel and sustenance for microbial life.<br /> <br /> <b>Atmospheric CO₂ has been relatively stable over the eons but huge, occasional catastrophic carbon disturbances have taken place</b><br /> <br /> DCO scientists have reconstructed Earth's deep carbon cycle over eons to the present day. This new, more complete picture of the planetary ingassing and outgassing of carbon shows a remarkably stable system over hundreds of millions of years, with a few notable episodic exceptions.<br /> <br /> Continental breakup and associated volcanic activity are the dominant causes of natural planetary outgassing. DCO scientists added to this picture by investigating rare episodes of massive volcanic eruptions and asteroid impacts to learn how Earth and its climate responds to such catastrophic carbon disturbances.<br /> <br /> Plate tectonics modeling using DCO's new GPlates platform made it possible to reconstruct the Earth's carbon cycle through geologic time.<br /> <br /> <b>Much of the carbon outgassed from Deep Earth seeps from fractures and faults unassociated with eruptions</b><br /> <br /> Volcanoes and volcanic regions outgas carbon dioxide (CO₂) into the ocean / atmosphere system at a rate of 280-360 megatonnes per year. This includes both emissions during volcanic eruptions and degassing of CO₂ out of diffuse fractures and faults in volcanic regions worldwide and the mid-ocean ridge system.<br /> <br /> Human activities, such as burning fossil fuels, are responsible for about 100 times more CO₂ emissions than all volcanic and tectonic region sources combined.<br /> <br /> <b>The changing ratio of CO₂ to SO₂ emitted by volcanoes may help forecast eruptions</b><br /> <br /> The volume of outgassed CO₂ relative to SO₂increases for some volcanoes days to weeks before an eruption, raising the possibility of improved forecasting and mitigating danger to humans.<br /> <br /> DCO researchers measured volcanic outputs around the globe. Italy's Mount Etna, for example, one of Earth's most active volcanoes, typically spewed 5 to 8 times more CO₂ than usual about two weeks before a large eruption.<br /> <br /> <b>Fluids move and transform carbon deep within Earth</b><br /> <br /> Experiments and new theoretical work led to a revolutionary new DCO model of water in deep Earth and the discovery that diamonds can easily form through water-rock interactions involving organic and inorganic carbon.<br /> <br /> This model predicted the changing chemistry of water found in fluid inclusions in diamonds and yields new insights into the amounts of carbon and nitrogen available for return to Earth's atmosphere over deep time.<br /> <br /> DCO scientists also discovered that the solubility of carbon-bearing minerals, including carbonates, graphite, and diamond, is much higher than previously thought in water-rock systems in the mantle.<br /> <br /> <b>31 new carbon-bearing minerals found in four years</b><br /> <br /> After cataloguing known carbon-bearing minerals at Earth's surface, their composition and where they are found, DCO researchers discovered statistical relationships between mineral localities and the frequency of their occurrence. With that model they predicted 145 yet-to-be-discovered species and in 2015 challenged citizen scientists to help find them.<br /> <br /> Of the 31 new-to-science minerals turned up during the Carbon Mineral Challenge, two had been predicted, including triazolite, discovered in Chile and thought to have derived in part from cormorant guano. Photo below.<br /> <br /> Meanwhile, scientists led by DCO Executive Director Robert Hazen, established an entirely new mineral classification system.<br /> <br /> Through experiment and observation, DCO scientists discovered new forms of carbon deep in Earth's mantle, shedding new light on the carbon "storage capacity" of the deep mantle, and on the role of subduction in recycling surface carbon back to Earth's interior.<br /> <br /> Studies also cast new light on the record of major changes in our planet's history such as the rise of oxygen and the waxing and waning of supercontinents.<br /> <br /> <b>Two-thirds of Earth's carbon may be in the iron-rich core</b><br /> <br /> DCO research suggests that two-thirds or more of Earth's carbon may be sequestered in the core as a form of iron carbide. This "hidden carbon" brings the total carbon content of Earth closer to what is observed in the Sun and helps us to understand the origin of Earth's carbon from celestial material.</div> <div style="text-align: left;"> <br /></div> <div style="text-align: left;"> <br /></div> <i><span style="font-family: "trebuchet ms" , sans-serif;">The above story is based on <a href="https://deepcarbon.net/imperfect-diamonds-paved-way-historic-new-deep-earth-discoveries" rel="nofollow" target="_blank">Materials</a> provided by <a href="https://deepcarbon.net/" rel="nofollow" target="_blank">Deep Carbon Observatory</a></span></i></div>

Imperfect Diamonds Paved Road to Historic Deep Earth Discoveries

 31 new-to-science minerals have turned up (including triazolite, discovered in Chile, thought to have derived in part from cormorant gua...

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Gold Nugget Turns Out To be Four-Billion-Year-Old Meteorite

<div dir="ltr" style="text-align: left;" trbidi="on"> <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody> <tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-jtKxWv6hbYw/XgeJYgbCrmI/AAAAAAAARxo/HJRV4C8Lpf4svyW8kKFD2SchmY0qUI4IACLcBGAsYHQ/s1600/Gold%2BNugget%2BTurns%2BOut%2BTo%2Bbe%2BFour-Billion-Year-Old%2BMeteorite.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="813" data-original-width="1220" height="426" src="https://1.bp.blogspot.com/-jtKxWv6hbYw/XgeJYgbCrmI/AAAAAAAARxo/HJRV4C8Lpf4svyW8kKFD2SchmY0qUI4IACLcBGAsYHQ/s640/Gold%2BNugget%2BTurns%2BOut%2BTo%2Bbe%2BFour-Billion-Year-Old%2BMeteorite.jpg" width="640" /></a></td></tr> <tr><td class="tr-caption" style="text-align: center;">The Marborough meteorite. photo: (Melbourne Museum)</td></tr> </tbody></table> <br /> Back in May 2015, an Australian prospector set off to scour the Maryborough Regional Park in search of his fortune, but instead of striking gold, he came across something that was – unfortunately for him – priceless. Intrigued by the density and weight of a slightly odd-looking reddish rock, David Hole spent the next four years attempting to crack open this seemingly impenetrable specimen, only to eventually discover that it was in fact a 4.6-billion-year-old meteorite.<br /> <br /> Mr Hole stumbled upon the find with the help of a metal detector while digging for gold near Melbourne, in a region that had become synonymous with the precious metal during the 19th-century gold-rush. Hoping to find a nugget inside the rock, he later attempted to access its interior using everything from acid to a sledgehammer, without success.<br /> <br /> Baffled as to why the rock was so reluctant to reveal its inner secrets, he decided to take it to the Melbourne Museum, where it was identified as a meteorite.<br /> <br /> Scientists used a diamond saw to slice off a sliver of the ancient space rock, discovering that it was in fact an H chondrite. The most common type of meteorite, H chondrites contain a high percentage of iron and make up about 40 percent of all meteorites ever found.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> Describing the rock, Melbourne Museum geologist Dermot Henry told the Sydney Morning Herald that “it had this sculpted, dimpled look to it,” which resulted from the outside of the meteorite melting as it plunged through Earth’s atmosphere.<br /> <br /> The object’s extreme weight is attributed to some of the metals it contains, including dense forms of iron and nickel. It is also speckled with droplets of metals called chondrules, which formed during the early stages of the Solar System’s development before later becoming embedded in an asteroid.<br /> <br /> The meteorite has been named Maryborough after the place where it was found, and carbon dating suggests it crash-landed between 100 and 1,000 years ago.<br /> <br /> Describing the specimen in the Proceedings of the Royal Society of Victoria, the team lists a number of recorded meteorite sightings from the annals of history that could possibly correlate to Maryborough. One such sighting was reported by a Harry E. Hallett in a letter to The Argus in June 1923.<br /> <br /> Addressing the editors, he describes how the “brilliant meteor… almost dazzled me, and horses out in the paddocks neighed such a neigh of fear that I will never forget it.”<br /> <br /> Weighing 17 kilograms (37.5 pounds), the Maryborough meteor is the second largest ever to be found in the state of Victoria.<br /> <br /> It's not even the first meteorite to take a few years to make it to a museum. In a particularly amazing story we covered last year, one space rock took 80 years, two owners, and a stint as a doorstop before making it to a museum.<br /> <br /> Now is probably as good a time as any to check your backyard for particularly heavy and hard-to-break rocks - you might be sitting on a metaphorical gold mine.<br /> <br /> <br /> <u><i><span style="font-family: "trebuchet ms" , sans-serif;">The research has been published in <a href="http://www.publish.csiro.au/RS/RS19002" rel="nofollow" target="_blank">Proceedings of the Royal Society of Victoria</a>.</span></i></u></div>

Gold Nugget Turns Out To be Four-Billion-Year-Old Meteorite

The Marborough meteorite. photo: (Melbourne Museum) Back in May 2015, an Australian prospector set off to scour the Maryborough Region...

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Mysterious Tectonic Fault Zone Found Off California

<div dir="ltr" style="text-align: left;" trbidi="on"> <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody> <tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-SP373LZuGfM/XgY2fI01Y_I/AAAAAAAARxc/mBiGUayBeqwLXMRWU7vu1Z7TciFybPjHwCLcBGAsYHQ/s1600/MARS%2Bcable%2Bin%2BMonterey%2BBay%2Bwith%2Bpink%2Bportion%2Bused%2Bfor%2Bsensing.%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Mysterious Tectonic Fault Zone Found Off California" border="0" data-original-height="773" data-original-width="1210" height="408" src="https://1.bp.blogspot.com/-SP373LZuGfM/XgY2fI01Y_I/AAAAAAAARxc/mBiGUayBeqwLXMRWU7vu1Z7TciFybPjHwCLcBGAsYHQ/s640/MARS%2Bcable%2Bin%2BMonterey%2BBay%2Bwith%2Bpink%2Bportion%2Bused%2Bfor%2Bsensing.%2B%25281%2529.jpg" title="" width="640" /></a></td></tr> <tr><td class="tr-caption" style="text-align: center;">MARS cable in Monterey Bay with pink portion used for sensing. </td></tr> </tbody></table> <br /> <div style="text-align: left;"> Nearly 3,000 feet (900 metres) below the surface of Monterey Bay, a network of deep sea cables helps scientists to study marine life.<br /> <br /> Spanning 32 miles (51 kilometres) across the floor of the Pacific Ocean, the cables record sounds like the high-pitched squeal of a dolphin or the deep moans of a humpback whale. They also capture the emission of light from undersea organisms like poisonous algae.<br /> <br /> But a team of researchers from Rice University and the University of California, Berkeley, have discovered another use for the network: recording underwater earthquakes.<br /> <br /> Last year, the researchers conducted a four-day experiment using 12 miles (19 kilometres) of the cable network to study the motion of the seafloor. The results of that experiment appear in a new paper in the journal Science.<br /> <br /> The researchers reveal that they detected a 3.5-magnitude earthquake in Gilroy, a city in Northern California, in March 2018. They also discovered a new fault system at the bottom of the ocean. The technology could eventually help them map fault lines in areas where scientists know very little about seismic activity on the ocean floor.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> "It's kind of like streetlamps shining light on an area of the seafloor," Nate Lindsey, the paper's lead author, told Business Insider. "There's a lot of potential to go and do this in an area where it makes a difference."</div> <br /> <h4 style="text-align: left;"> <span style="font-family: "georgia" , "times new roman" , serif;">Researchers discovered a new fault system underwater</span></h4> <div style="text-align: left;"> </div> Before the researchers conducted their experiment at sea, they tested their technology on land using underground fibre-optic cables from the US Department of Energy, which funded the project. The cables stretch 13,000 miles (20,000 kilometres) below ground in Sacramento, California, but the researchers only used 14 miles for their experiment.<br /> <br /> To start, they attached a device to the end of the cables that shoots out bursts of light. When the ground moves, it places a strain on the cables that scatters the light and sends it hurtling back toward the device. These light waves can be measured to determine the magnitude of an earthquake.<br /> <br /> After six months of experimenting on land, the researchers moved their technology underwater. They partnered with the Monterey Accelerated Research System (MARS), which operates a network of undersea fibre-optic cables.<br /> <br /> Every year, the cables need to be taken offline for maintenance, giving the researchers a brief window to test their technology.<br /> <br /> For their experiment, the researchers used a portion of the cables that stretches from Moss Landing, a small fishing village off the coast of Monterey Bay, to Soquel Canyon, an offshore marine protected area.<br /> <br /> By installing their device at the end of the undersea cables, the researchers were able to monitor shifts and fractures at the bottom of the ocean. This led to the discovery of a new underwater fault system in the Pacific Ocean in-between two major fault lines, the San Gregorio and the San Andreas, which run parallel to each other.<br /> <br /> Lindsey said the fault system is likely "much, much smaller" and "minor" compared to the San Andreas – which scientists have pinpointed as the likely source of the next major California earthquake.<br /> <div style="margin: 0px auto; width: 100%;"> <script async="" src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script><br /> <ins class="adsbygoogle" data-ad-client="ca-pub-1021498709184325" data-ad-format="fluid" data-ad-layout="in-article" data-ad-slot="6157425841" style="display: block; text-align: center;"></ins><br /> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script><br /></div> But he said his technology could ultimately be used to identify larger fault lines in unexplored areas like offshore Taiwan.<br /> <br /> <h4> <span style="font-family: "georgia" , "times new roman" , serif;">Cables could monitor earthquakes across long stretches of land and sea</span></h4> <div style="text-align: left;"> </div> Since most of Earth's surface – around 70 percent – is covered in water, scientists don't have many ways to measure offshore earthquakes.<br /> <br /> Jonathan Ajo-Franklin, a geophysics professor at Rice University who worked on the experiment, said systems like the one from MARS – which are tethered to the shore by a cable – are so rare that you could count them on one hand. He estimated that just three or four operate at one time on the West Coast.<br /> <br /> "In every case, it's limited scope in terms of the length of the experiment and it's high cost," Lindsey said. The MARS observatory, for instance, cost around US$13.5 million.<br /> <br /> But Lindsey still thinks cable networks are the best way to study underwater seismic activity. Other ocean researchers share his enthusiasm.<br /> <br /> John Collins, a senior researcher at the Woods Hole Oceanographic Institution who didn't work on the study, called the technique "very promising". Bruce Howe, a physical oceanographer at the University of Hawaii, also thought the system could provide useful data.<br /> <br /> "It's based on good physics, so I think it will pan out," Howe, who also wasn't involved in the study, told Business Insider.<br /> <br /> On land, traditional earthquake sensors typically measure the speed of the ground motion at a single point. But fibre-optic cables allow researchers to take multiple measurements across a long path.<br /> <br /> "For every metre of cable, you're measuring a stretch of tens of nanometres or even smaller," Ajo-Franklin said. That's about the width of a human hair.<br /> <br /> The MARS system, for instance, can record measurements at 10,000 locations, meaning it has the same capacity as 10,000 individual motion sensors. That gives researchers lots of data points for studying how earthquakes rattle across the ocean.<br /> <br /> When the 3.5-magnitude earthquake struck Gilroy last year, the researchers were able to record the tremors of the ocean waves – a tool that might eventually help with the early detection of tsunamis.<br /> <br /> "The nice thing about recording that earthquake was not necessarily locating it," Ajo-Franklin said.<br /> <br /> "When you have densely sampled locations, you can do a lot more with the earthquake's wavefield to allow you to build pictures of what's on the ground."<br /> <br /> <br /> <u><i><span style="font-family: "trebuchet ms" , sans-serif;">The study was published in the journal <a href="https://science.sciencemag.org/content/366/6469/1103" rel="nofollow" target="_blank">journal Science.</a></span></i></u></div>

Mysterious Tectonic Fault Zone Found Off California

MARS cable in Monterey Bay with pink portion used for sensing. Nearly 3,000 feet (900 metres) below the surface of Monterey Bay, a ne...

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