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How Rare Minerals Form When Meteorites Slam Into Earth

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The discovery of a rare mineral (reidite) at the Woodleigh meteorite impact structure in Western Australia was published this week by Curtin University honours student Morgan Cox and colleagues.<br />
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Reidite – and other minerals – are sometimes formed when meteorites crash into Earth.<br />
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This takes a particular set of circumstances. Only six prior discoveries of reidite had ever been reported.<br />
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Here’s what happens when a meteorite slams into Earth.</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">Rocks from space</span></h4>
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Our planet is continuously bombarded by meteorites – rocks from space – and has been since its formation about four and half billion years ago.<br />
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These objects include rocky and metallic asteroids, comets and other debris left over after the formation of the solar system, rock fragments ejected off planet surfaces from impact events and potentially even rare visitors that have travelled from outside our Solar system.<br />
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Space objects range in size from tiny particles to huge asteroids. They are usually travelling towards us at velocities of many kilometres per second – so-called hypervelocities.<br />
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Fortunately for us, though, small rocks are the most common, and Earth’s atmosphere simultaneously slows them down, burns them away and breaks them up. We can often see this happening as fireballs and meteor showers. Any surviving chunks of rock free fall to the Earth’s surface to be collected as meteorites.<br />
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The Fireballs in the Sky team at Curtin University has an amazing network of cameras to track incoming fireballs and predict the final land location of meteorites – and work out where in the Solar System they came from. They’ve made some great meteorite discoveries in this way.<br />
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Some rocks never make the final landing. Some may also produce an airburst – an atmospheric pressure wave that can cause damage like at Chelyabinsk in Russia in 2013. Here, an asteroid approximately 20 metres across and travelling at 19 km per second exploded about 30 km above the ground, causing a blast that was strong enough blow out windows of buildings in six nearby cities.</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">Too big to slow down</span></h4>
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Some incoming rocks are too big for our atmosphere to slow down, and these are much more rare.<br />
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These slam into the Earth at hypervelocities, which imparts a huge amount of energy and causes impact craters. The size of an impact crater mainly depends on the dimensions, density and speed of the meteorite.<br />
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There are many known impact craters in Australia, such as Wolfe Creek in the Kimberly, and Gosses Bluff near Alice Springs. We also know of craters that are now buried under layers of recent sedimentary rocks, such as Woodleigh, Western Australia.<br />
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Globally, around 190 impact craters (or their eroded remnants) have been discovered on Earth – a lot fewer than scientists predict should have formed over all of Earth’s history.<br />
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This is because the Earth’s surface is quite a dynamic place, and processes of erosion and plate tectonics act to erase evidence of impact craters over time.<br />
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The known craters range in diameter from a few metres to a few hundred kilometres across, and range in age from a few thousand years to approximately two billion years.<br />
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No impact craters have formed in recent history, so scientists rely on studying ancient craters in combination with laboratory experiments and computer simulations to figure out what happens during such catastrophic events.</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">Speed and pressure</span></h4>
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A hypervelocity impact event puts the impactor (that is, the rock arriving from space) and “ground zero” target rocks under immense pressure, which propagates through the Earth as a shock wave faster than the speed of sound.<br />
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It is not uncommon for the rocks to reach pressures in the tens or even hundreds of gigapascals – equivalent to a hundred billion times the pressure of Earth’s atmosphere. Even in the fractions of a second that rocks spend at these pressures, some minerals transform into new “high-pressure” minerals.<br />
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For example, graphite can form diamonds, and the mineral zircon can turn into reidite – as described in the new paper.<br />
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As the shock wave passes, heat energy is produced by the release from high pressure. This can heat the rocks enough to melt, and in many cases even completely vaporise the meteorite and rocks at ground zero.<br />
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Shock waves also cause a lot of damage to rocks. They may break into fragments and get ejected high into the atmosphere and even into space, leaving behind a bowl-shaped crater.<br />
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Eventually the shock wave loses energy, so it slows down and becomes less destructive, and ripples through the Earth as seismic waves similar to those emitted during an earthquake.</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">Earth changed forever</span></h4>
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In huge impact events – like the one that caused extinction of the dinosaurs and the 180 km across Chicxulub Crater in the gulf of Mexico – the centre of the crater is pushed upwards to form a central peak or peak ring.<br />
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It is quite alarming to think that all of these things occur within seconds to minutes of an impact, and can leave long-lasting scars on Earth’s surface, cause significant environmental effects, and even result in mass extinctions.<br />
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Impact craters are relics of truly catastrophic events on Earth. Rare mineral formation is just one of the possible outcomes when rocks arrive from space.</div>
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<i><u><span style="font-family: "trebuchet ms" , sans-serif;">This article is republished from <a href="https://theconversation.com/how-rare-minerals-form-when-meteorites-slam-into-earth-105129" rel="nofollow" target="_blank">The Conversation</a> under a Creative Commons license. </span></u></i></div>
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How Rare Minerals Form When Meteorites Slam Into Earth

Photo: © Sputnik / Vladimir Pesnya The discovery of a rare mineral (reidite) at the Woodleigh meteorite impact structure in Wester...

Climate Change Could Lead to Global Beer Crisis

climate, Researches 8:37 PM

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Climate change threatens to cause global prices to soar along with global temperatures, as droughts and extreme heat result in shrunken yields of barley, according to a new scientific report.<br />
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The study warns that increasingly widespread and severe drought and heat may cause substantial decreases in barley yields worldwide, affecting the supply used to make beer, and ultimately resulting in "dramatic" falls in beer consumption and rises in beer prices.<br />
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Beer is the most popular alcoholic drink in the world by volume consumed. Although the frequency and severity of drought and heat extremes increase substantially in a range of future climate scenarios, the vulnerability of beer supply to such extremes has never been assessed.<br />
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In recent years, the beer sector has consumed around 17% of global barley production, but this share varies drastically across major beer-producing countries, for example from 83% in Brazil to 9% in Australia. Results from the new study reveal potential average yield losses ranging from 3% to 17%, depending on the severity of the conditions. Decreases in the global supply of barley lead to proportionally larger decreases in barley used to make beer.<br />
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During the most severe climate events, the results indicate that global beer consumption would decline by 16%, or 29 billion litres -- roughly equal to the total annual beer consumption in the US -- and that beer prices would on average double. Even in less severe extreme events, beer consumption drops by 4% and prices rise by 15%.<br />
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The findings, published today in Nature Plants, suggest that total beer consumption decreases most under climate change in the countries that consumed the most beer by volume in recent years. For example, the volume consumed in China -- today the largest consuming country -- falls by more than any other country as the severity of extreme events increases, and by 4.34 billion litres in the most severe.<br />
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In the UK, beer consumption could fall by between 0.37 billion and 1.33 billion litres, while the price could as much as double. Consumption in the US could decrease by between 1.08 billion and 3.48 billion litres.<br />
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Co-ordinator of the research and lead UK author Dabo Guan, professor of climate change economics at UEA's School of International Development, said: "Increasingly research has begun to project the impacts of climate change on world food production, focusing on staple crops such as wheat, maize, soybean, and rice.<br />
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"However, if adaptation efforts prioritise necessities, climate change may undermine the availability, stability and access to 'luxury' goods to a greater extent than staple foods. People's diet security is equally important to food security in many aspects of society.<br />
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"Although some attention has been paid to the potential impacts of climate change on luxury crops such as wine and coffee, the impacts on beer have not been carefully evaluated. A sufficient beer supply may help with the stability of entertainment and communication in society."<br />
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Prof Guan added: "While the effects on beer may seem modest in comparison to many of the other -- some life-threatening -- impacts of climate change, there is nonetheless something fundamental in the cross-cultural appreciation of beer.<br />
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"It may be argued that consuming less beer isn't itself disastrous, and may even have health benefits. Nevertheless, there is little doubt that for millions of people around the world, the climate impacts on beer availability and price will add insult to injury."<br />
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The international study involved researchers from the UK, China, Mexico, and the US, who identified extreme climate events and modelled the impacts of these on barley yields in 34 world regions. They then examined the effects of the resulting barley supply shock on the supply and price of beer in each region under a range of future climate scenarios.<br />
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Some countries with smaller total beer consumption face huge reductions in their beer consumption: the volume of beer consumed in Argentina falls by 0.53 billion litres, equivalent to a 32% reduction, during more severe climate events. Even in the least severe climate events, total beer consumption in Argentina and Canada decreases by 0.27 billion litres (16%) and 0.22 billion litres (11%) respectively.<br />
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Countries where beer is currently most expensive, for example Australia and Japan, are not necessarily where future price shocks will be the greatest. Changes in the price of beer in a country relates to consumers' ability and willingness to pay more for beer rather than consume less, such that the largest price increases are concentrated in relatively affluent and historically beer-loving countries.<br />
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The researchers suggest that changes in barley supply due to extreme events will affect the barley available for making beer differently in each region, as the allocation of barley among livestock feed, beer brewing, and other uses will depend on region-specific prices and demand flexibilities as different industries seek to maximize profits.<br />
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Their findings show that global and country-level barley supply declines progressively in more severe extreme event years, with the largest mean supply decreasing by 27-38% in some European countries, such as Belgium, the Czech Republic and Germany.<br />
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<u><span style="font-family: "trebuchet ms" , sans-serif;">The above story is based on <a href="http://www.uea.ac.uk/about/-/study-reveals-how-climate-change-could-cause-global-beer-shortages" rel="nofollow" target="_blank">Materials</a> provided by <a href="http://comm.uea.ac.uk/" rel="nofollow" target="_blank">University of East Anglia</a>.</span></u></div>

Climate Change Could Lead to Global Beer Crisis

Photo: Getty Images Climate change threatens to cause global prices to soar along with global temperatures, as droughts and extreme h...

Chrysanthemum Stone: Natural Flower Stone

Mineralogy, Rocks 7:34 PM

Chrysanthemum Stone: Natural Flower Stone

Photo: cobalt123 The chrysanthemum stone is approximately 270 million years old. It is a dark gray to black limestone matrix with and...

Michigan Man Discovers His Doorstop Actually a Meteorite Worth $100,000

Meteorite, News, USA 7:44 PM

Michigan Man Discovers His Doorstop Actually a Meteorite Worth $100,000

The Edmore meteorite found in northeast Montcalm County in the 1930s and made public this year is Michigan's sixth largest, weighing ...

Rare Snail Found in Dinosaur-era Amber

amber, dinosaur 4:57 PM

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<tr><td class="tr-caption" style="text-align: center;">Photo courtesy of Associate Professor Lida Xing, China University of Geosciences, Beijing.</td></tr>
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Palaeontologists have found - so perfectly preserved that its delicate shell is intact, and prehistoric soft snail tissues have been observed for the first time. A second, less well-preserved snail shell is also in the same chunk of amber.<br />
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An international research team from China, UK, Canada, and Monash University has discovered the first and oldest preserved soft tissue of a terrestrial gastropod – a snail – in the fossil record.<br />
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The discovery is highlighted in a study published in the journal Cretaceous Research.<br />
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“We have demonstrated the exceptional preservation potential of amber (fossilised tree resin) with the discovery for the first time of soft tissues preserved in a snail, approximately 99 million years old, that lived in a hot, tropical environment in an ancient greenhouse Earth setting,” said study co-author Associate Professor Jeffrey Stilwell, a palaeontologist from the Monash School of Earth, Atmosphere and Environment.<br />
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“It is absolutely extraordinary for the fossil record to produce such stunning preservation, which is exceedingly rare for any fossil of this age, especially snails and many other animals,” he said.<br />
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The discovery is the first and oldest preserved soft tissue of a snail in the fossil record from the mid-Cretaceous of Myanmar.<br />
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The snail dates from c99 million years ago and is preserved in amber/burmite with its cephalic (head) region and tentacle with eye spot and inferred operculum (the trap-door of the snail).<br />
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The combined evidence from both hard and soft parts indicates that the snails have a cyclophoroidean ancestry with modern relatives of this group living in tropical and subtropical habitats.<br />
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“Our research reveals that it is possible to preserve fossilised remains nearly 100 million years old with the extraordinary preservation of both hard and soft parts, even the most delicate of structures, such as a tentacle with eye spot of a forest-dwelling topical snail,” Associate Professor Stilwell said.<br />
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<tr><td class="tr-caption" style="text-align: center;">The oldest terrestrial snail recorded from the fossil record with soft tissue preserved, including the head region with tentacle and eye spot and also the inferred operculum.  The cyclophoroidean gastropod dates to approximately 99 million years ago and is stunningly preserved in amber (ancient tree resin) from Myanmar. <br />
Photo courtesy of Associate Professor Lida Xing, China University of Geosciences, Beijing.</td></tr>
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The oldest marine snails are from the Late Cambrian to Ordovician of North America.<br />
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“It is extremely rare for palaeontologists to have any soft parts to confirm an identity of the snail, which is the realm of malacology today,” Associate Professor Stilwell said.<br />
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Many of these terrestrial gastropods had similar morphologies, which made it challenging to assign them to particular groups.<br />
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“We were really fortunate in the burmite specimen to have the tentacle and position of the eye spot and also the inferred operculum,” Associate Professor Stilwell said.<br />
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“The extraordinary aspect of the discovery is to actually see the soft parts of a nearly 100- Million-year-old snail.”<br />
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Associate Professor Stilwell said most snails retracted into their shells when threatened, so the research team was very fortunate to have an example from the fossil record.<br />
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<u><i><span style="font-family: "trebuchet ms" , sans-serif;"> The above story is based on <a href="https://www.monash.edu/science/news/current/major-fossil-find-sheds-new-light-on-the-life-a-100-million-year-old-snail" rel="nofollow" target="_blank">materials</a> provided by <a href="https://www.monash.edu/" rel="nofollow" target="_blank">Monash University.</a></span></i></u></div>
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Rare Snail Found in Dinosaur-era Amber

Photo courtesy of Associate Professor Lida Xing, China University of Geosciences, Beijing. Palaeontologists have found - so perfec...

Mount Etna's Slide Into the Sea Could Trigger a Catastrophic Collapse

Tectonic, volcano 6:06 PM

Mount Etna's Slide Into the Sea Could Trigger a Catastrophic Collapse

Photograph by Am Design Gravity is pulling Mount Etna toward the sea, raising the possibility that the flank of the active volca...

4-Billion-Year-Old Crystals Offer Clues to the Origins of Life

Crystal, Earth History 7:20 PM

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What did earth look like more than 4 billion years ago? This was before humans carved its wonders on stone, before trees etched the seasons in their rings, before plate tectonics buckled Earth’s surface to expose the ancient layers in growing mountain belts.<br />
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But scientists do have some clues in the form of an extremely tough mineral known as zircon.<br />
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Zircon crystals are almost indestructible; some still around today are nearly 4.4 billion years old. They're like tiny time capsules that retain the chemical fingerprints of this extremely early time. “This is basically our only window into the formative stages of our planet,” says Dustin Trail of the University of Rochester.<br />
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By decoding these chemical clues, scientists are slowly teasing out the environments that fostered the earliest glimmers of life. But exactly what the surface looked like at that time has long remained a mystery. Now, in a new study published in Proceedings of the National Academy of Sciences, Trail and his colleagues pick apart the enigma.<br />
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Using the chemical fingerprints of zircons, the team identified an array of sediments likely present on early Earth, where the oldest biochemical reactions could have brewed.</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">The Ultimate Recycler</span></h4>
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When Earth first formed, more than 4.5 billion years ago, its surface likely looked nothing like it does today. Scientists often paint this period—aptly named the Hadean after Hades, the Greek god of the underworld—as a fiery hellscape under constant meteoric assault, replete with volcanoes gurgling lava at the surface.<br />
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But all of this is based on inference—no physical evidence remains from Earth's first few hundred million years. “The Earth has done a great job erasing some of that information,” Trail says. Our planet is the ultimate recycler. Plate tectonics constantly repurpose old rock into new, and lava flows harden into fresh landscapes.<br />
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Zircon crystals, however, are so tough that they often survive the intense temperatures and pressures of this recycling process, retaining clues about the environments in which they originally formed. Using zircon oxygen isotopes, researchers previously discovered that liquid water covered parts of our planet some 4.3 billion years ago, suggesting the surface cooled just a few hundred million years after our planet’s formation. And just last year, researchers found what they believe might be hints of early life in the form of carbon-rich inclusions in 4.1-billion-year-old zircons.<br />
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But aside from these glimpses, the scenery on Earth’s surface during this time—including the environments that might have fostered these earliest sparks of life—largely remain a mystery.<br />
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“If we can begin to constrain the types of materials that are around at that time,” Trail says, “that perhaps pushes us one step closer to understanding how biochemical reactions, or prebiotic reactions, may have utilized the crust at that time as a substrate.”</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">Chemical Traces</span></h4>
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For answers, Trail and his colleagues turned to silicon and oxygen. Together, these elements make up roughly 75 percent of the rocks on Earth today, he explains. And both have a useful feature: they have more than one type, or isotope.<br />
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The formation, and transformation, of rocks changes their isotopic fingerprint. For example, rocks that form from cooling lava have vastly different signatures than clays that come from weathered rocks. And zircons—themselves starting off as different rock and sediment types before being buried deep in the Earth, melting, and then crystallizing—still hold the signature of those early sediments.<br />
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To conduct the delicate analysis of silicon and oxygen contained in the zircons, the team turned to the high-resolution ion microprobe at the University of California, Los Angeles, which shoots a fine beam of charged atoms at the tiny samples and measures the ejected ions that bounce back.<br />
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For the test, they collected zircons just older than 4 billion years—each about 100 microns across or roughly the width of a human hair—from the Jack Hills region of Western Australia. They compared the chemistry of these ancient minerals to that of younger zircons with more definitive origins as a “bridge” to help interpret the different ratios of isotopes, Trail explains.</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">A Picture of Early Earth</span></h4>
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More than half of the ancient zircons tested reveal early interactions between water and rock, in a range of different environments.<br />
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Some zircons contain the chemical signatures of rocks weathered by water to form clay. Other zircons bear the signatures of dissolved minerals that crystallize to form rocks like chert or banded iron formations in lakes or oceans. Still others have the signature of a process known as serpentinization, so called for its snake-skin-like texture and color. During this process, water reacts with rocks enriched in iron and magnesium, incorporating itself into the mineral structures.<br />
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 Most importantly, each of these processes creates a new environmental niche that could foster early biochemical reactions, the glimmers of early life.<br />
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“That's a pretty cool result,” says Elizabeth Bell, a geochemist at the University of California, Los Angeles, who was not involved in the work. Many of these processes are largely indistinguishable from oxygen isotopes alone, she notes, calling the use of silicon "really significant.”<br />
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Bell led the 2017 work that identified hints of a biosphere in 4.1-billion-year-old zircons. These latest results bolster her findings and other interpretations of early Earth. “It sort of all comes together in a nice picture,” she says.<br />
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Everything around (and within) us once came from stardust, and the early processes that formed every molecule, mineral, and complex organism of today—from your cell phone to the food you eat to the heart pumping in your chest. And scientists are just beginning to tease out their origins.<br />
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“We're at a really interesting point,” Trail says. “We're beginning to really piece together what our planet was like more than 4 billion years ago. And that's pretty exciting.”</div>
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<u><i><span style="font-family: "trebuchet ms" , sans-serif;">The above post is reprinted from <a href="https://www.nationalgeographic.com/science/2018/09/news-earth-rocks-sediment-first-life-zircon/" rel="nofollow" target="_blank">National Geographic.</a></span></i></u></div>
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<u><i><span style="font-family: "trebuchet ms" , sans-serif;">The study published in <a href="http://www.pnas.org/cgi/doi/10.1073/pnas.1808335115" rel="nofollow" target="_blank">Proceedings of the National Academy of Sciences.</a></span></i></u> </div>
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4-Billion-Year-Old Crystals Offer Clues to the Origins of Life

What did earth look like more than 4 billion years ago? This was before humans carved its wonders on stone, before trees etched the se...

What Are Rare Earths, Crucial Elements in Modern Technology?

Geology, Mining, Researches 6:01 PM

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<tr><td class="tr-caption" style="text-align: center;">A handful of europium.</td></tr>
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Most Americans use rare earth elements every day – without knowing it, or knowing anything about what they do.<br />
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Stanley Mertzman, a geologist whose specialty is X-ray analysis of rocks and minerals to determine their chemical composition, and who teaches mineralogy at Franklin and Marshall College, explains more about these little-known and fascinating elements – and the modern electronics they make possible.</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">1. What are rare earth elements?</span></h3>
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Strictly speaking, they are elements like others on the periodic table – such as carbon, hydrogen and oxygen – with atomic numbers 57 to 71. There are two others with similar properties that are sometimes grouped with them, but the main rare earth elements are those 15. To make the first one, lanthanum, start with a barium atom and add one proton and one electron. Each successive rare earth element adds one more proton and one more electron.<br />
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It’s significant that there are 15 rare earth elements: Chemistry students may recall that when electrons are added to an atom, they collect in groups or layers, called orbitals, which are like concentric circles of a target around the bull’s-eye of the nucleus.<br />
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The innermost target circle of any atom can contain two electrons; adding a third electron means adding one in the second target circle. That’s where the next seven electrons go, too – after which electrons must go to the third target circle, which can hold 18. The next 18 electrons go into the fourth target circle.<br />
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Then things start to get a bit odd. Though there is still room for electrons in the fourth target circle, the next eight electrons go into the fifth target circle. And despite more room in the fifth, the next two electrons after that go into the sixth target circle.<br />
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That’s when the atom becomes barium, atomic number 56, and those empty spaces in earlier target circles start to fill. Adding one more electron – to make lanthanum, the first in the series of rare earth elements – puts that electron in the fifth circle. Adding another, to make cerium, atomic number 58, adds an electron to the fourth circle. Making the next element, praseodymium, actually moves the newest electron in the fifth circle to the fourth, and adds one more. From there, additional electrons fill up the fourth circle.<br />
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In all elements, the electrons in the outermost circle largely influence the element’s chemical properties. Because the rare earths have identical outermost electron configurations, their properties are quite similar.</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">2. Are rare earth elements really rare?</span></h3>
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No. They’re much more abundant in the Earth’s crust than many other valuable elements. Even the rarest rare earth, thulium, with atomic number 69, is 125 times more common than gold. And the least-rare rare earth, cerium, with atomic number 58, is 15,000 times more abundant than gold.</div>
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They are rare in one sense, though – mineralogists would call them “dispersed,” meaning they’re mostly sprinkled across the planet in relatively low concentrations. Rare earths are often found in rare igneous rocks called carbonatites – nothing so common as basalt from Hawaii or Iceland, or andesite from Mount St. Helens or Guatemala’s Volcano Fuego.<br />
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There are a few regions that are have lots of rare earths – and they’re mostly in China, which produces more than 80 percent of the global annual total of 130,000 metric tons. Australia has a few areas too, as do some other countries. The U.S. has a little bit of area with lots of rare earths, but the last American source for them, California’s Mountain Pass Quarry, closed in 2015.</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">3. If they’re not rare, are they very expensive?</span></h3>
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Yes, quite. In 2018, the cost for an oxide of neodymium, atomic number 60, is US$107,000 per metric ton. The price is expected to climb to $150,000 by 2025.<br />
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Europium is even more costly – about $712,000 per metric ton.<br />
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Part of the reason is that rare earth elements can be chemically difficult to separate from each other to get a pure substance.</div>
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<span style="font-family: "georgia" , "times new roman" , serif;">4. What are rare earth elements useful for?</span></h3>
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In the last half of the 20th century, europium, with atomic number 63, came in to wide demand for its role as a color-producing phosphor in video screens, including computer monitors and plasma <br />
TVs. It’s also useful for absorbing neutrons in nuclear reactors’ control rods.<br />
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Other rare earths are also commonly used in electronic devices today. Neodymium, atomic number 60, for instance, is a powerful magnet, useful in smartphones, televisions, lasers, rechargeable batteries and hard drives. An upcoming version of Tesla’s electric car motor is also expected to use neodymium.<br />
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Demand for rare earths has risen steadily since the middle of the 20th century, and there are no real alternative materials to replace them. As important as rare earths are to a modern technology-based society, and as difficult as they are to mine and use, the tariff battle may put the U.S. in a very bad place, turning both the country and rare earth elements themselves into pawns in this game of economic chess.</div>
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<i><u><span style="font-family: "trebuchet ms" , sans-serif;">The above post is reprinted from  <a href="http://theconversation.com/" rel="nofollow" target="_blank">The Conversation</a>. Read the <a href="http://theconversation.com/what-are-rare-earths-crucial-elements-in-modern-technology-4-questions-answered-101364" rel="nofollow" target="_blank">original article</a>.<img src="https://counter.theconversation.com/content/101364/count.gif?distributor=republish-lightbox-advanced" /> </span></u></i><span style="background-color: white; color: #717171; display: inline; float: none; font-family: "arial" , "helvetica" , sans-serif; font-size: 11.648px; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;"><br />
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What Are Rare Earths, Crucial Elements in Modern Technology?

A handful of europium. Most Americans use rare earth elements every day – without knowing it, or knowing anything about what they d...

A Geyser Erupted in Yellowstone and 80 Years of Human Trash Poured Out

Environment, Yellowstone 8:12 PM

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On Sept. 15, Yellowstone National Park's Ear Spring geyser erupted in its most violent display since 1957. For several minutes, sprays of steaming water leapt up to 30 feet (9 meters) in the air, chunks of rock and dirt spewed forth onto the ground and about 60 years of wishes were promptly reversed when the geyser gave up nearly 100 coins that had previously been tossed in.<br />
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Some coins were to be expected: Who among us hasn't flipped a good-luck penny into a thermal vent? But park officials were more surprised to find that decades of man-made garbage had also burst forth from Ear Spring — some of which dated back to the 1930s.<br />
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"After Ear Spring erupted on September 15, employees found a strange assortment of items strewn across the landscape around its vent," officials wrote on the Yellowstone National Park Facebook page. "Some are clearly historic: they'll be inventoried by curators and may end up in Yellowstone's archives."<br />
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What have people been throwing into the geyser? Some of the historical detritus that Ear Spring coughed up includes a large chunk of cinderblock, a broken bottle, several metal warning signs, some old aluminum cans, plastic cups, cigarette butts, someone's rubber heel insert, a vintage pacifier from the 1930s and an 8-inch-long (20 centimeters) plastic drinking straw. (Editor's note: please do not try to drink a geyser.)<br />
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Whether these foreign objects were dropped into the geyser accidentally or chucked in on purpose makes no difference. Either way, park officials wrote, it's bad for the geyser.<br />
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</div>"Foreign objects can damage hot springs and geysers," park officials wrote on Facebook. "The next time Ear Spring erupts we hope it's nothing but natural rocks and water."<br />
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According to the U.S. Geological Survey (USGS), Ear Spring has erupted four times in the last 60 years, most recently in 2004. The geyser is located on Yellowstone's Geyser Hill, not far from the world-famous gusher Old Faithful. Several other geysers and thermal pools showed increased activity around the time of Ear Spring's eruption: For instance, a brand-new vent popped up and erupted overnight between Sept. 18 and 19.<br />
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"An approximately 8-foot [2.4 m] diameter area of surrounding ground is 'breathing' – rising and falling by about six inches [15 cm] every 10 minutes," USGS experts wrote in a news release.<br />
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This increased hydrothermal activity could last anywhere from a few days to several years, the USGS wrote. It could also result in a "small hydrothermal explosion" that would carve out a shallow crater on Geyser Hill while spewing jets of boiling water and rocks hundreds of feet in the air.<br />
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This is all to say, if you have been meaning to dispose of your old cinder block or vintage baby gear collection in a Yellowstone geyser, now is not the time.</div>

A Geyser Erupted in Yellowstone and 80 Years of Human Trash Poured Out

On Sept. 15, Yellowstone National Park's Ear Spring geyser erupted in its most violent display since 1957. For several minutes, sprays...