May 2021

World’s First Nuclear Bomb Test Created Rare, Otherworldly Crystal

<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-LZKmje5Dt98/YLT2yGh-86I/AAAAAAAATC8/DxlaF1wVFI4xnQZH9gNoF4bQUVsWlm8XACLcBGAsYHQ/s1200/World%25E2%2580%2599s%2BFirst%2BNuclear%2BBomb%2BTest%2BCreated%2BRare%252C%2BOtherworldly%2BCrystal.jpeg" style="margin-left: auto; margin-right: auto;"><img alt="World’s First Nuclear Bomb Test Created Rare, Otherworldly Crystal" border="0" data-original-height="926" data-original-width="1200" height="494" src="https://1.bp.blogspot.com/-LZKmje5Dt98/YLT2yGh-86I/AAAAAAAATC8/DxlaF1wVFI4xnQZH9gNoF4bQUVsWlm8XACLcBGAsYHQ/w640-h494/World%25E2%2580%2599s%2BFirst%2BNuclear%2BBomb%2BTest%2BCreated%2BRare%252C%2BOtherworldly%2BCrystal.jpeg" title="World’s First Nuclear Bomb Test Created Rare, Otherworldly Crystal" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">World’s First Nuclear Bomb Test Created Rare, Otherworldly Crystal. This sample of red trinitite, forged during the world's first nuclear bomb test, contains a crystal never seen before on Earth. (Image credit: Luca Bindi and Paul J. Steinhardt.) </td></tr></tbody></table>  Newly Discovered Quasicrystal – “Magnificent in Its Complexity” – Was Created by the First Nuclear Explosion at Trinity Site A newly discovered quasicrystal that was created by the first nuclear explosion at Trinity Site, N.M., on July 16, 1945, could someday help scientists better understand illicit nuclear explosions and curb nuclear proliferation.  In an instant, a metal-coated plutonium device named "Gadget" imploded, creating a gargantuan fireball that rose high into the sky, vaporizing everything it touched. Sand melted into radioactive glass, and a crater nearly as wide as a football field dented the planet. The test — codenamed Trinity — was a success. But Trinity didn't just destroy; it also left something strange and new behind. In a study published in the journal Proceedings of the National Academy of Sciences, researchers have detected otherworldly crystals called "quasicrystals" trapped in the bomb-blasted rocks at the Trinity site. These odd gems, which lack the perfect symmetry of true crystals, are usually only seen in meteorites from the early solar system, and are thought to be forged only in the extreme heat and pressure of the universe's most powerful explosions. These newfound crystals, embedded in the rubble of the Trinity site, provide scientists with proof that quasicrystals can also result from mankind's most explosive creations, according to the study authors. These crystals give nuclear researchers "a new tool in the toolbox" for analyzing the power and impact of past nuclear explosions, both in the U.S. and abroad, study co-author Terry Wallace, director emeritus of Los Alamos National Laboratory in New Mexico, said in a video accompanying the research. "Understanding another country's nuclear weapons requires that we have a clear understanding of their nuclear testing programs," Wallace said in a statement. "We typically analyze radioactive debris and gases to understand how the weapons were built or what materials they contained, but those signatures decay. A quasicrystal that is formed at the site of a nuclear blast … [will] exist forever." When the plutonium Gadget detonated on July 16, the resulting fireball was hotter than Earth's sun, Wallace said. The heat and force of this explosion were so strong that the metal test tower and surrounding sand melted together into a new type of glass, later named trinitite. Most trinitite samples are green, like a pale glass bottle. But rarer samples are red, presumably because they contain greater amounts of copper and other metals from the test tower and recording equipment at the site. In their new study, Wallace and his colleagues examined a red trinitite specimen under an electron microscope, looking specifically at metallic "blobs" that might contain crystals. In this sample, the team detected a five-sided quasicrystal with an atomic structure never seen on Earth before. The crystal was made predominantly of silicon from the desert sand, but also contained proportionally high amounts of copper, plus some iron and calcium. The crystal is "magnificent in its complexity," Wallace said — and it's still not clear to his team exactly how or why it formed this way. One thing is clear, though: This quasicrystal has an "unmistakable" origin, based on its composition, radioactivity and discovery location, the researchers said. It's a unique crystal forged in the fires of America's first nuclear blast, and therefore is the oldest human-made quasicrystal on Earth. Similar crystals could lurk in the rubble of other nuclear test sites — and studying the unique structures of those crystals could reveal important information about the nature of the bombs that created them, Wallace said. Unlocking that knowledge will require a lot more study — and many more crystal samples — but ultimately, it will be worth it to better understand the cosmic-level explosions that humans have learned to unleash here on Earth.  The above story is based on <a href="https://www.pnas.org/content/118/22/e2101350118" rel="nofollow" target="_blank">materials </a>provided by <a href="https://www.pnas.org/" rel="nofollow" target="_blank">PNAS</a>.

World’s First Nuclear Bomb Test Created Rare, Otherworldly Crystal

World’s First Nuclear Bomb Test Created Rare, Otherworldly Crystal. This sample of red trinitite, forged during the world's first nuclea...

Rare Purple-pink Diamond Breaks Auction Record

Diamonds, News 7:05 PM

Rare Purple-pink Diamond Breaks Auction Record

“The Sakura,” a 15.8-carat purple-pink diamond set on a platinum and gold ring, sold for $29.3 million. A purple-pink diamond has set a ne...

Hawaii’s Kilauea Volcano Stops Erupting After Months of Lava

Hawaii, volcano 6:33 PM

Hawaii’s Kilauea Volcano Stops Erupting After Months of Lava

(Credit: A. Lerner, USGS. Public domain.) Hawaii’s Kilauea Volcano Finally Stops Erupting After 157 Days and 11 Billion Gallons of Lava Hawa...

Alaska Volcano Eruption at Great Sitkin Island Sparks Red Warning

News, USA, volcano 6:15 PM

<div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-5vJfPleGy5k/YK5lR2uqTzI/AAAAAAAATCQ/jzyWPTPAbNAVxIGT9EMRJXmupLzoENoqwCLcBGAsYHQ/s1328/Alaska%2BVolcano%2BErupts%2B%2527Explosive%2527%2B15%252C000ft%2BAsh%2BCloud%2BSent%2BInto%2BSky%2B-%2BAlert%2BLevel%2Bat%2BRed%2B%25281%2529.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="779" data-original-width="1328" height="235" src="https://1.bp.blogspot.com/-5vJfPleGy5k/YK5lR2uqTzI/AAAAAAAATCQ/jzyWPTPAbNAVxIGT9EMRJXmupLzoENoqwCLcBGAsYHQ/w400-h235/Alaska%2BVolcano%2BErupts%2B%2527Explosive%2527%2B15%252C000ft%2BAsh%2BCloud%2BSent%2BInto%2BSky%2B-%2BAlert%2BLevel%2Bat%2BRed%2B%25281%2529.jpg" title="Alaska Volcano Erupts: 'Explosive' 15,000ft Ash Cloud Sent Into Sky - Alert Level at Red" width="400" /></a></div>  Alaska Volcano Erupts: 'Explosive' 15,000ft Ash Cloud Sent Into Sky - Alert Level at RedAvolcanic eruption from the Alaskan volcano of Great Sitkin has launched ash high into the air and further explosions are possible, according to the authorities. <blockquote class="twitter-tweet">AVO Great Sitkin RED/WARNING - Explosive eruption began at 21:04 AKDT (5:04 UTC 26 May) and is continuing. <a href="https://t.co/8gDGARtWVM">https://t.co/8gDGARtWVM</a>— USGS Volcanoes🌋 (@USGSVolcanoes) <a href="https://twitter.com/USGSVolcanoes/status/1397425020683526144?ref_src=twsrc%5Etfw">May 26, 2021</a></blockquote> <script async="" charset="utf-8" src="https://platform.twitter.com/widgets.js"></script>The Alaska Volcano Observatory (AVO) has issued a red aviation alert for Great Sitkin, meaning "significant emission" of volcanic ash into the atmosphere is likely. The eruption does not appear to have sparked any evacuation warnings. The observatory issued a notice for aircraft at around 6 a.m. UTC Wednesday morning in which it warned an "explosive eruption" occurred about an hour prior, sending up a cloud of volcanic ash. The eruption is thought to have lasted between one and two minutes. Initial reports suggested the cloud from the eruption was 15,000ft high. Since that explosion the cloud has detached from the volcano and is moving eastward. AVO has warned additional explosions are possible. The Aviation Color Code warning remains red, and the Volcano Alert Level remains at "Warning." It is unclear at the time of writing how the eruption may affect or has affected flights over the region. Volcanic ash is known to have damaging effects on aircraft because it can erode crucial components such as turbine blades in the engine and scratch landing lights and windscreens. It can also block fuel nozzles and air filters, set off fire alarms in the cabin, interfere with radio communication systems, and block sensors that let the pilots know how fast the aircraft is going. The continuous monitoring of airspace helps airline companies avoid volcanic ash clouds. Great Sitkin is a volcano that occupies most of the northern half of Great Sitkin Island, which is part of the Aleutian Islands chain. The volcano is oval-shaped, eight by 11 kilometers at its base, and 5,709ft tall. It is about 26 miles east of the community of Adak, and around 1,167 miles away from Anchorage, Alaska's most populous city, which is to the north east. The last time Great Sitkin erupted was in 1974, marking at least the third time it had done so during the 20th century.

Alaska Volcano Eruption at Great Sitkin Island Sparks Red Warning

Alaska Volcano Erupts: 'Explosive' 15,000ft Ash Cloud Sent Into Sky - Alert Level at Red Avolcanic eruption from the Alaskan volca...

Clues From Soured Milk Reveal How Gold Veins Form

Geochemistry, Geology, Gold 6:08 PM

<div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-SBQfzNlSH-w/YKpr9ml9UrI/AAAAAAAATBs/4iF8IpTMds8XUJVpUu501wegvu30o8xWwCLcBGAsYHQ/s1300/Clues%2BFrom%2BSoured%2BMilk%2BReveal%2BHow%2BGold%2BVeins%2BForm%2B%25281%2529.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="867" data-original-width="1300" height="266" src="https://1.bp.blogspot.com/-SBQfzNlSH-w/YKpr9ml9UrI/AAAAAAAATBs/4iF8IpTMds8XUJVpUu501wegvu30o8xWwCLcBGAsYHQ/w400-h266/Clues%2BFrom%2BSoured%2BMilk%2BReveal%2BHow%2BGold%2BVeins%2BForm%2B%25281%2529.jpg" width="400" /></a></div>  For decades scientists have been puzzled by the formation of rare hyper-enriched gold deposits in places like Ballarat in Australia, Serra Palada in Brazil, and Red Lake in Ontario. While such deposits typically form over tens to hundreds of thousands of years, these "ultrahigh-grade" deposits can form in years, month, or even days. So how do they form so quickly? Studying examples of these deposits from the Brucejack Mine in northwestern British Columbia, McGill Professor Anthony Williams-Jones of the Department of Earth and Planetary Sciences and PhD student Duncan McLeish have discovered that these gold deposits form much like soured milk. When milk goes sour, the butterfat particles clump together to form a jelly. Q&A with Anthony Williams-Jones and Duncan McLeish <h4 style="text-align: left;">What did you set to find out?</h4>Scientists have long known that gold deposits form when hot water flows through rocks, dissolving minute amounts of gold and concentrating it in cracks in the Earth's crust at levels invisible to the naked eye. In rare cases, the cracks are transformed into veins of solid gold centimetres thick. But how do fluids with such low concentrations of gold produce rare ultrahigh-grade gold deposits? <h4 style="text-align: left;">What did you discover?</h4>Our findings solve the paradox of "ultrahigh-grade" or "bonanza" gold formation, which has frustrated scientists for over a century. The paradox of bonanza gold deposits is that there is simply not enough time for them to form, they should not exist, but they do! <div style="width:100%;margin: 0px auto">
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</div> As the concentration of gold in hot water is very low, very large volumes of fluid need to flow through the cracks in the Earth's crust to deposit mineable concentrations of gold. This process would require millions of years to fill a single centimetre wide crack with gold, whereas these cracks typically seal in days, months, or years. Using a powerful electron microscope to observe particles in thin slices of rock, we discovered that bonanza gold deposits form from a fluid much like milk. Milk consists of little butterfat particles that are suspended in water because they repel each other, like the negative ends of two magnets. When the milk goes sour the surface charge breaks down, and the particles clump together to form a jelly. It is the same with gold colloids, which consist of charged nanoparticles of gold which repel each other, but when the charge breaks down, they "flocculate" to form a jelly. This jelly gets trapped in the cracks of rocks to form the ultra high-grade gold veins. The gold colloids are distinctively red and can be made in the lab, whereas solutions of dissolved gold are colourless. <h4 style="text-align: left;">Why are the results important?</h4>We produced the first evidence for gold colloid formation and flocculation in nature and the first images of small veins of gold colloid particles and their flocculated aggregates at the nano-scale. These images document the process by which the cracks are filled with gold and, scaled up through the integration of millions of these small veins, reveal how bonanza veins are formed. <h4 style="text-align: left;">How will this discovery impact the mining industry?</h4>Our results are important to the mineral exploration and mining industry in Canada and around the world. Now that we finally understand how bonanza deposits form, mineral exploration companies will be able to use the results of our work to better explore for bonanza deposits as well as gold deposits. Genetic studies of Canada's most fertile metallogenic districts - such as the one we have just completed at Brucejack - are required to improve our understanding of how world-class mineral deposits form, and thereby develop more effective strategies for their exploration. <h4 style="text-align: left;">What's next for this research?</h4>We suspect that the colloidal processes that operated at Brucejack and other bonanza gold systems may also have operated to form more typical gold deposits. The challenge will be to find suitable material to test this hypothesis. At Brucejack, the next step will be to better understand the reasons why colloid formation and flocculation occurred on the scale observed and reconstruct the geological environment of these processes. We have also been preparing gold colloids in the lab in an attempt to simulate what we discovered at Brucejack. The above story is based on <a href="https://www.mcgill.ca/newsroom/channels/news/clues-soured-milk-reveal-how-gold-veins-form-331173" rel="nofollow" target="_blank">materials </a>provided by <a href="https://www.mcgill.ca/" rel="nofollow" target="_blank">Mcgill University.</a>

Clues From Soured Milk Reveal How Gold Veins Form

For decades scientists have been puzzled by the formation of rare hyper-enriched gold deposits in places like Ballarat in Australia, Serra...

Plate Tectonics Are 3.6 Billion Years Old, Oldest Minerals on Earth Reveal

Earth History, Geology, Tectonic 8:49 PM

<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-Nd2IgjiwdeM/YKP9i1m7KUI/AAAAAAAATBI/axjJEaE04CEvMEFLemxoX_ooYVQXmid_gCLcBGAsYHQ/s1198/Plate%2BTectonics%2BAre%2B3.6%2BBillion%2BYears%2BOld%252C%2BOldest%2BMinerals%2Bon%2BEarth%2BReveal.jpg" style="margin-left: auto; margin-right: auto;"><img alt="Plate Tectonics Are 3.6 Billion Years Old, Oldest Minerals on Earth Reveal" border="0" data-original-height="784" data-original-width="1198" height="418" src="https://1.bp.blogspot.com/-Nd2IgjiwdeM/YKP9i1m7KUI/AAAAAAAATBI/axjJEaE04CEvMEFLemxoX_ooYVQXmid_gCLcBGAsYHQ/w640-h418/Plate%2BTectonics%2BAre%2B3.6%2BBillion%2BYears%2BOld%252C%2BOldest%2BMinerals%2Bon%2BEarth%2BReveal.jpg" title="Plate Tectonics Are 3.6 Billion Years Old, Oldest Minerals on Earth Reveal" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Plate Tectonics Are 3.6 Billion Years Old, Oldest Minerals on Earth Reveal. Earth's oldest minerals </td></tr></tbody></table>  Scientists led by Michael Ackerson, a research geologist at the Smithsonian’s National Museum of Natural History, provide new evidence that modern plate tectonics, a defining feature of Earth and its unique ability to support life, emerged roughly 3.6 billion years ago. Earth is the only planet known to host complex life and that ability is partly predicated on another feature that makes the planet unique: plate tectonics. No other planetary bodies known to science have Earth’s dynamic crust, which is split into continental plates that move, fracture and collide with each other over eons. Plate tectonics afford a connection between the chemical reactor of Earth’s interior and its surface that has engineered the habitable planet people enjoy today, from the oxygen in the atmosphere to the concentrations of climate-regulating carbon dioxide. But when and how plate tectonics got started has remained mysterious, buried beneath billions of years of geologic time. The study, published in the journal Geochemical Perspective Letters, uses zircons, the oldest minerals ever found on Earth, to peer back into the planet’s ancient past. The oldest of the zircons in the study, which came from the Jack Hills of Western Australia, were around 4.3 billion years old—which means these nearly indestructible minerals formed when the Earth itself was in its infancy, only roughly 200 million years old. Along with other ancient zircons collected from the Jack Hills spanning Earth’s earliest history up to 3 billion years ago, these minerals provide the closest thing researchers have to a continuous chemical record of the nascent world. “We are reconstructing how the Earth changed from a molten ball of rock and metal to what we have today,” Ackerson said. “None of the other planets have continents or liquid oceans or life. In a way, we are trying to answer the question of why Earth is unique, and we can answer that to an extent with these zircons.” To look billions of years into Earth’s past, Ackerson and the research team collected 15 grapefruit-sized rocks from the Jack Hills and reduced them into their smallest constituent parts—minerals—by grinding them into sand with a machine called a chipmunk. Fortunately, zircons are very dense, which makes them relatively easy to separate from the rest of the sand using a technique similar to gold panning. The team tested more than 3,500 zircons, each just a couple of human hairs wide, by blasting them with a laser and then measuring their chemical composition with a mass spectrometer. These tests revealed the age and underlying chemistry of each zircon. Of the thousands tested, about 200 were fit for study due to the ravages of the billions of years these minerals endured since their creation. “Unlocking the secrets held within these minerals is no easy task,” Ackerson said. “We analyzed thousands of these crystals to come up with a handful of useful data points, but each sample has the potential to tell us something completely new and reshape how we understand the origins of our planet.” A zircon’s age can be determined with a high degree of precision because each one contains uranium. Uranium’s famously radioactive nature and well-quantified rate of decay allow scientists to reverse engineer how long the mineral has existed. The aluminum content of each zircon was also of interest to the research team. Tests on modern zircons show that high-aluminum zircons can only be produced in a limited number of ways, which allows researchers to use the presence of aluminum to infer what may have been going on, geologically speaking, at the time the zircon formed. After analyzing the results of the hundreds of useful zircons from among the thousands tested, Ackerson and his co-authors deciphered a marked increase in aluminum concentrations roughly 3.6 billion years ago. “This compositional shift likely marks the onset of modern-style plate tectonics and potentially could signal the emergence of life on Earth,” Ackerson said. “But we will need to do a lot more research to determine this geologic shift’s connections to the origins of life.” The line of inference that links high-aluminum zircons to the onset of a dynamic crust with plate tectonics goes like this: one of the few ways for high-aluminum zircons to form is by melting rocks deeper beneath Earth’s surface. “It’s really hard to get aluminum into zircons because of their chemical bonds,” Ackerson said. “You need to have pretty extreme geologic conditions.” Ackerson reasons that this sign that rocks were being melted deeper beneath Earth’s surface meant the planet’s crust was getting thicker and beginning to cool, and that this thickening of Earth’s crust was a sign that the transition to modern plate tectonics was underway. Prior research on the 4 billion-year-old Acasta Gneiss in northern Canada also suggests that Earth’s crust was thickening and causing rock to melt deeper within the planet. “The results from the Acasta Gneiss give us more confidence in our interpretation of the Jack Hills zircons,” Ackerson said. “Today these locations are separated by thousands of miles, but they’re telling us a pretty consistent story, which is that around 3.6 billion years ago something globally significant was happening.” This work is part of the museum’s new initiative called Our Unique Planet, 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 helped spark life. Ackerson said he hopes to follow up these results by searching the ancient Jack Hills zircons for traces of life and by looking at other supremely old rock formations to see if they too show signs of Earth’s crust thickening around 3.6 billion years ago. The above story is based on <a href="https://www.si.edu/newsdesk/releases/earths-oldest-minerals-date-onset-plate-tectonics-36-billion-years-ago#:~:text=But%20when%20and%20how%20plate,into%20the%20planet's%20ancient%20past." rel="nofollow" target="_blank">materials </a>provided by <a href="https://www.nasa.gov/" rel="nofollow" target="_blank">the National Aeronautics and Space Administration (NASA). </a>

Plate Tectonics Are 3.6 Billion Years Old, Oldest Minerals on Earth Reveal

Plate Tectonics Are 3.6 Billion Years Old, Oldest Minerals on Earth Reveal. Earth's oldest minerals Scientists led by Michael Ackerson...

Researchers Discover Geologic Process 'Tearing Apart' Plates of the Earth's Crust

Earth History, Geology, Tectonic 6:50 PM

<div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-ZsAt7-VzqG8/YJ_shLBRkUI/AAAAAAAAS-Y/78mZqidqKFkFj9iHwYT1Sw-F2FMroRjyACLcBGAsYHQ/s1200/Researchers%2Bdiscover%2Bgeologic%2Bprocess%2B%2527tearing%2Bapart%2527%2Bplates%2Bof%2Bthe%2BEarth%2527s%2Bcrust%2B%25281%2529.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="800" data-original-width="1200" height="426" src="https://1.bp.blogspot.com/-ZsAt7-VzqG8/YJ_shLBRkUI/AAAAAAAAS-Y/78mZqidqKFkFj9iHwYT1Sw-F2FMroRjyACLcBGAsYHQ/w640-h426/Researchers%2Bdiscover%2Bgeologic%2Bprocess%2B%2527tearing%2Bapart%2527%2Bplates%2Bof%2Bthe%2BEarth%2527s%2Bcrust%2B%25281%2529.jpg" title="Researchers discover geologic process 'tearing apart' plates of the Earth's crust" width="640" /></a></div> Geoscientists at the University of Toronto (U of T) and Istanbul Technical University have discovered a new process in plate tectonics which shows that tremendous damage occurs to areas of Earth's crust long before it should be geologically altered by known plate-boundary processes, highlighting the need to amend current understandings of the planet's tectonic cycle. Plate tectonics, an accepted theory for over 60 years that explains the geologic processes occurring below the surface of Earth, holds that its outer shell is fragmented into continent-sized blocks of solid rock, called "plates," that slide over Earth's mantle, the rocky inner layer above the planet's core. As the plates drift around and collide with each other over million-years-long periods, they produce everything from volcanoes and earthquakes to mountain ranges and deep ocean trenches, at the boundaries where the plates collide. Now, using supercomputer modelling, the researchers show that the plates on which Earth's oceans sit are being torn apart by massive tectonic forces even as they drift about the globe. The findings are reported in a study published this week in Nature Geoscience. The thinking up to now focused only on the geological deformation of these drifting plates at their boundaries after they had reached a subduction zone, such as the Marianas Trench in the Pacific Ocean where the massive Pacific plate dives beneath the smaller Philippine plate and is recycled into Earth's mantle. The new research shows much earlier damage to the drifting plate further away from the boundaries of two colliding plates, focused around zones of microcontinents -- continental crustal fragments that have broken off from main continental masses to form distinct islands often several hundred kilometers from their place of origin. "Our work discovers that a completely different part of the plate is being pulled apart because of the subduction process, and at a remarkably early phase of the tectonic cycle," said Erkan Gün, a PhD candidate in the Department of Earth Sciences in the Faculty of Arts & Science at U of T and lead author of the study. The researchers term the mechanism a "subduction pulley" where the weight of the subducting portion that dives beneath another tectonic plate, pulls on the drifting ocean plate and tears apart the weak microcontinent sections in an early phase of potentially significant damage. "The damage occurs long before the microcontinent fragment reaches its fate to be consumed in a subduction zone at the boundaries of the colliding plates," said Russell Pysklywec, professor and chair of the Department of Earth Sciences at U of T, and a coauthor of the study. He says another way to look at it is to think of the drifting ocean plate as an airport baggage conveyor, and the microcontinents are like pieces of luggage travelling on the conveyor. "The conveyor system itself is actually tearing apart the luggage as it travels around the carousel, before the luggage even reaches its owner." The researchers arrived at the results following a mysterious observation of major extension of rocks in alpine regions in Italy and Turkey. These observations suggested that the tectonic plates that brought the rocks to their current location were already highly damaged prior to the collisional and mountain-building events that normally cause deformation. "We devised and conducted computational Earth models to investigate a process to account for the observations," said Gün. "It turned out that the temperature and pressure rock histories that we measured with the virtual Earth models match closely with the enigmatic rock evolution observed in Italy and Turkey." According to the researchers, the findings refine some of the fundamental aspects of plate tectonics and call for a revised understanding of this fundamental theory in geoscience. "Normally we assume -- and teach -- that the ocean plate conveyor is too strong to be damaged as it drifts around the globe, but we prove otherwise," said Pysklywec. The findings build on the legacy of J. Tuzo Wilson, also a U of T scientist, and a renowned figure in geosciences who pioneered the idea of plate tectonics in the 1960s. The above story is based on <a href="https://www.utoronto.ca/news/researchers-discover-geologic-process-tearing-apart-plates-earth-s-crust" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; color: #004276; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;" target="_blank">Materials</a><span style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline !important; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;"> provided by <a href="https://www.utoronto.ca/" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; color: #004276; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;" target="_blank">University of Toronto</a><span style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline !important; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;">. Original written by Sean Bettam.

Researchers Discover Geologic Process 'Tearing Apart' Plates of the Earth's Crust

Geoscientists at the University of Toronto (U of T) and Istanbul Technical University have discovered a new process in plate tectonics which...

Scientists Find A New Way To Tell Ages And Origins Of Diamonds

Diamonds, Earth History 5:09 AM

<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-ZiZIDjsyN34/YJs4QLMyKzI/AAAAAAAAS-I/_cFLOw3und0V8cdC80nADZcv3vyZjgOJwCLcBGAsYHQ/s2048/Scientists%2BFind%2BA%2BNew%2BWay%2BTo%2BTell%2BAges%2BAnd%2BOrigins%2BOf%2BDiamonds%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1536" data-original-width="2048" height="480" src="https://1.bp.blogspot.com/-ZiZIDjsyN34/YJs4QLMyKzI/AAAAAAAAS-I/_cFLOw3und0V8cdC80nADZcv3vyZjgOJwCLcBGAsYHQ/w640-h480/Scientists%2BFind%2BA%2BNew%2BWay%2BTo%2BTell%2BAges%2BAnd%2BOrigins%2BOf%2BDiamonds%2B%25281%2529.jpg" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">A Diamond Used in the Study. Credit: Yaakov Weiss</td></tr></tbody></table>  Diamonds are sometimes described as messengers from the deep earth; scientists study them closely for insights into the otherwise inaccessible depths from which they come. But the messages are often hard to read. Now, a team has come up with a way to solve two longstanding puzzles: the ages of individual fluid-bearing diamonds, and the chemistry of their parent material. The research has allowed them to sketch out geologic events going back more than a billion years -- a potential breakthrough not only in the study of diamonds, but of planetary evolution. Gem-quality diamonds are nearly pure lattices of carbon. This elemental purity gives them them their luster; but it also means they carry very little information about their ages and origins. However, some lower-grade specimens harbor imperfections in the form of tiny pockets of liquid -- remnants of the more complex fluids from which the crystals evolved. By analyzing these fluids , the scientists in the new study worked out the times when different diamonds formed, and the shifting chemical conditions around them. "It opens a window -- well, let's say, even a door -- to some of the really big questions" about the evolution of the deep earth and the continents, said lead author Yaakov Weiss, an adjunct scientist at Columbia University's Lamont-Doherty Earth Observatory, where the analyses were done, and senior lecturer at the Hebrew University of Jerusalem. "This is the first time we can get reliable ages for these fluids." The study was published this week in the journal Nature Communications. Most diamonds are thought to form some 150 to 200 kilometers under the surface, in relatively cool masses of rock beneath the continents. The process may go back as far as 3.5 billion years, and probably continues today. Occasionally, they are carried upward by powerful, deep-seated volcanic eruptions called kimberlites. (Don't expect to see one erupt today; the youngest known kimberlite deposits are tens of millions of years old.) Much of what we know about diamonds comes from lab experiments, and studies of other minerals and rocks that come up with the diamonds, or are sometimes even encased within them. The 10 diamonds the team studied came from mines founded by the De Beers company in and around Kimberley, South Africa. "We like the ones that no one else really wants," said Weiss -- fibrous, dirty-looking specimens containing solid or liquid impurities that disqualify them as jewelry, but carry potentially valuable chemical information. Up to now, most researchers have concentrated on solid inclusions, such as tiny bits of garnet, to determine the ages of diamonds. But the ages that solid inclusions indicate can be debatable, because the inclusions may or may not have formed at the same time as the diamond itself. Encapsulated fluids, on the other hand, are the real thing, the stuff from which the diamond itself formed. What Weiss and his colleagues did was find a way to date the fluids. They did this by measuring traces of radioactive thorium and uranium, and their ratios to helium-4, a rare isotope that results from their decay. The scientists also figured out the maximum rate at which the nimble little helium molecules can leak out of the diamond -- without which data, conclusions about ages based on the abundance of the isotope could be thrown far off. (As it turns out, diamonds are very good at containing helium.) The team identified three distinct periods of diamond formation. These all took place within separate rock masses that eventually coalesced into present-day Africa. The oldest took place between 2.6 billion and 700 million years ago. Fluid inclusions from that time show a distinct composition, extremely rich in carbonate minerals. The period also coincided with the buildup of great mountain ranges on the surface, apparently from the collisions and squishing together of the rocks. These collisions may have had something to do with production of the carbonate-rich fluids below, although exactly how is vague, the researchers say. The next diamond-formation phase spanned a possible time frame of 550 million to 300 million years ago, as the proto-African continent continued to rearrange itself. At this time, the liquid inclusions show, the fluids were high in silica minerals, indicating a shift in subterranean conditions. The period also coincided with another major mountain-building episode. The most recent known phase took place between 130 million years and 85 million years ago. Again, the fluid composition switched: Now, it was high in saline compounds containing sodium and potassium. This suggests that the carbon from which these diamonds formed did not come directly from the deep earth, but rather from an ocean floor that was dragged under a continental mass by subduction. This idea, that some diamonds' carbon may be recycled from the surface, was once considered improbable, but recent research by Weiss and others has increased its currency. One intriguing find: At least one diamond encapsulated fluid from both the oldest and youngest eras. The shows that new layers can be added to old crystals, allowing individual diamonds to evolve over vast periods of time. It was at the end of this most recent period, when Africa had largely assumed its current shape, that a great bloom of kimberlite eruptions carried all the diamonds the team studied to the surface. The solidified remains of these eruptions were discovered in the 1870s, and became the famous De Beers mines. Exactly what caused them to erupt is still part of the puzzle. The tiny diamond-encased droplets provide a rare way to link events that took place long ago on the surface with what was going on at the same time far below, say the scientists. "What is fascinating is, you can constrain all these different episodes from the fluids," said Cornelia Class, a geochemist at Lamont-Doherty and coauthor of the paper. "Southern Africa is one of the best-studied places in the world, but we've very rarely been able to see beyond the indirect indications of what happened there in the past." When asked whether the findings could help geologists find new diamond deposits, Weiss just laughed. "Probably not," he said. But, he said, the method could be applied to other diamond-producing areas of the world, including Australia, Brazil, and northern Canada and Russia, to disentangle the deep histories of those regions, and develop new insights into how continents evolve. "These are really big questions, and it's going to take people a long time to get at them," he said. "I will go to pension, and still not have finished that walk. But at least this gives us some new ideas about how to find out how things work." The other authors of the study are Yael Kiro of Israel's Weizmann Institute of Science; Gisela Winckler and Steven Goldstein of Lamont-Doherty; and Jeff Harris of Scotland's University of Glasgow. The above story is based on <a href="https://news.climate.columbia.edu/2021/05/11/hidden-within-african-diamonds-a-billion-plus-years-of-deep-earth-history/" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; color: #004276; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;" target="_blank">Materials</a><span style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline !important; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;"> provided by <a href="https://www.earth.columbia.edu/" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; color: #004276; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;" target="_blank">Earth Institute at Columbia University</a><span style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline !important; float: none; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;">. Original written by Kevin Krajick.

Scientists Find A New Way To Tell Ages And Origins Of Diamonds

A Diamond Used in the Study. Credit: Yaakov Weiss Diamonds are sometimes described as messengers from the deep earth; scientists study the...

Sugilite: A Rare Precious Stone

Mineralogy, Minerals 4:37 AM

<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/--wriudocVOk/YJCkK-hWseI/AAAAAAAAS90/WSvURD0DHdEDjJi3mWdp-OMyyFIYIP1RQCLcBGAsYHQ/s1379/16kg%2BManganoan%2BSugilite.jpg" style="margin-left: auto; margin-right: auto;"><img alt="Sugilite: A Rare Precious Stone" border="0" data-original-height="1200" data-original-width="1379" height="556" src="https://1.bp.blogspot.com/--wriudocVOk/YJCkK-hWseI/AAAAAAAAS90/WSvURD0DHdEDjJi3mWdp-OMyyFIYIP1RQCLcBGAsYHQ/w640-h556/16kg%2BManganoan%2BSugilite.jpg" title="16kg Manganoan Sugilite" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Sugilite: A Rare Precious Stone. 16kg Manganoan Sugilite from Wessels Mine in Northern Cape Province, South Africa <span face="sans-serif" style="-webkit-text-stroke-width: 0px; background-color: #f8f9fa; color: black; display: inline; float: none; font-size: 12.32px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: center; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px;"> Photo: RDCnet CC </td></tr></tbody></table>Gem sugilite is a polycrystalline aggregate: a massive gem material that is colored a very attractive purple-violet color, due to the presence of manganese. It is named for Ken-ichi Sugi, the Japanese geologist who discovered it in 1944 on an island in Japan. Sugilite is a relatively rare pink to purple cyclosilicate mineral with the complex chemical formula KNa<sub style="-webkit-text-stroke-width: 0px; bottom: -0.25em; color: black; font-size: 12px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; line-height: 0; position: relative; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; vertical-align: baseline; white-space: normal; word-spacing: 0px;">2(Fe<sup style="-webkit-text-stroke-width: 0px; color: black; font-size: 12px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; line-height: 0; position: relative; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; top: -0.3em; vertical-align: baseline; white-space: normal; word-spacing: 0px;">3+,Mn<sup style="-webkit-text-stroke-width: 0px; color: black; font-size: 12px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; line-height: 0; position: relative; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; top: -0.3em; vertical-align: baseline; white-space: normal; word-spacing: 0px;">3+,Al)<sub style="-webkit-text-stroke-width: 0px; bottom: -0.25em; color: black; font-size: 12px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; line-height: 0; position: relative; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; vertical-align: baseline; white-space: normal; word-spacing: 0px;">2Li<sub style="-webkit-text-stroke-width: 0px; bottom: -0.25em; color: black; font-size: 12px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; line-height: 0; position: relative; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; vertical-align: baseline; white-space: normal; word-spacing: 0px;">3Si<sub style="-webkit-text-stroke-width: 0px; bottom: -0.25em; color: black; font-size: 12px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; line-height: 0; position: relative; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; vertical-align: baseline; white-space: normal; word-spacing: 0px;">12O<sub style="-webkit-text-stroke-width: 0px; bottom: -0.25em; color: black; font-size: 12px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; line-height: 0; position: relative; text-align: start; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; vertical-align: baseline; white-space: normal; word-spacing: 0px;">30. Sugilite crystallizes in the hexagonal system with prismatic crystals. The crystals are rarely found and the form is usually massive. It has a Mohs hardness of 5.5 to 6.5 and a specific gravity of 2.75 to 2.80. It is mostly translucent. Sugilite occurs in bedded manganese deposits as an aegirine-bearing syenite stock in biotite granite. This uncommon cyclosilicate mineral displays violet to purple-red coloring. Sugilite crystallizes in the hexagonal system with prismatic crystals. Although crystal specimens of sugilite are infrequently discovered, those that have been found they are usually very large. Sugilite deposits are found in Australia, India, Japan, Canada and South Africa. Sugilite is popular in jewelry, in thin sections which can be polished or cut into cabochons and mounted in silver or gold in rings, pendants, and earrings. In the 1980s the gem was heavily promoted on home shopping channels and internet auctions sites. With a Mohs scale hardness of 5-1/2 to 6-1/2, sugilite is somewhat durable. However, be careful wiping dust from sugilite because household dust contains quartz, which may cause scratches. It is recommended to clean sugilite gemstones by using soapy water, rinsing well and drying with a soft cloth. Ultrasonic cleaners and steamers are not recommended. Always remove any jewelry or gemstones before exercising, cleaning or engaging in physical activities such as sports. Store sugilite gemstones away from other gemstones to prevent scratches, wrapped in soft cloth or placed inside a fabric-lined box. See also: <a href="https://www.geologyin.com/2020/08/star-hollandite-quartz.html" target="_blank">Star Hollandite Quartz</a> <a href="https://www.geologyin.com/2020/02/chalcanthite-facts-about-chalcanthite.html" target="_blank">Chalcanthite: Facts About Chalcanthite</a> <a href="https://www.geologyin.com/2017/07/larimar-blue-stones-of-atlantis.html" target="_blank">Larimar: The Blue Stones of Atlantis</a>

Sugilite: A Rare Precious Stone

Sugilite: A Rare Precious Stone. 16kg Manganoan Sugilite from Wessels Mine in Northern Cape Province, South Africa Photo: RDCnet CC Gem sugi...

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