Vivid Violet Sugilite: A Rare Precious Stone

<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 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;"><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;">16kg Manganoan Sugilite from Wessels Mine in Northern Cape Province, South Africa <br />Photo: RDCnet CC<br /></span></td></tr></tbody></table><p>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.<br /><br />Sugilite is a relatively rare pink to purple cyclosilicate mineral with the complex chemical formula <span style="font-family: times;">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</sub>(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+</sup>,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+</sup>,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;">2</sub>Li<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;">3</sub>Si<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;">12</sub>O<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</sub></span>. 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.<br /><br />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.<br /><br />Sugilite deposits are found in Australia, India, Japan, Canada and South Africa.<br /><br />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.<br /><br />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. </p><p><span style="font-family: georgia;"><b>See also: </b></span></p><p><span style="font-family: georgia;"><a href="https://www.geologyin.com/2020/08/star-hollandite-quartz.html" target="_blank">Star Hollandite Quartz</a><br /><a href="https://www.geologyin.com/2020/02/chalcanthite-facts-about-chalcanthite.html" target="_blank"><span><span class="UHwcef">Chalcanthite: Facts About Chalcanthite</span></span></a><br /><a href="https://www.geologyin.com/2017/07/larimar-blue-stones-of-atlantis.html" target="_blank">Larimar: The Blue Stones of Atlantis</a></span><br /></p>

Vivid Violet Sugilite: A Rare Precious Stone

16kg Manganoan Sugilite from Wessels Mine in Northern Cape Province, South Africa Photo: RDCnet CC Gem sugilite is a polycrystalline aggrega...

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How Do Slow Anomalies Beneath Subducting Slabs Affect Giant Megathrust Earthquakes?

<p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-OZ9SbQEoxEo/YIoh7qtgB5I/AAAAAAAAS9c/5DCEGzN4viU1EYu46CKk09BKBoaddIeiwCLcBGAsYHQ/s1092/how-do-slow-anomalies-.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="764" data-original-width="1092" height="448" src="https://1.bp.blogspot.com/-OZ9SbQEoxEo/YIoh7qtgB5I/AAAAAAAAS9c/5DCEGzN4viU1EYu46CKk09BKBoaddIeiwCLcBGAsYHQ/w640-h448/how-do-slow-anomalies-.jpg" title="How Do Slow Anomalies Beneath Subducting Slabs Affect Giant Megathrust Earthquakes?" width="640" /></a></div> <br /><p></p><p> </p><p>Earthquakes and volcanoes in subduction zones may cause great human catastrophe. Previous studies on subduction zone structure and causal mechanisms of giant megathrust earthquakes (M ≥ 9.0) have mainly focused on aspects like subducting plates and plate interfaces.<br /><br />In contrast, the oceanic asthenosphere structure beneath the subducting slab (at depths of 100-250 km) and its influence on the nucleation of giant megathrust earthquakes have not been well studied.<br /><br />Recently, Dr. Fan Jianke from the Institute of Oceanology of the Chinese Academy of Sciences (IOCAS) and Prof. Zhao Dapeng from Tohoku University turned their attention to this problem by investigating the oceanic asthenosphere structure of six subduction zones where giant earthquakes have occurred.<br /><br />The researchers adopted P-wave tomographic inversions and compiled updated tomographic models. The tomographic images clearly reveal subslab low-velocity (slow) anomalies beneath forearc regions in the six subduction zones.<br /><br />"The giant earthquake hypocenters are generally located above the edges of the slow anomalies or above the gaps between them. Large coseismic slips of the giant earthquakes mainly occur above gaps between the slow anomalies," said Dr. Fan.<br /><br />The buoyancy force of a subslab slow anomaly can increase interplate shear stress by enhancing interplate normal stress. Interplate shear stress increases the critical stress threshold for rupture, and the critical shear stress above the slow anomaly gap is slightly smaller than that above the slow anomaly.<br /><br />However, critical shear stress is still large enough and relatively easier to reach. As such, it can induce a giant megathrust earthquake above the slow anomaly gap, which is primarily controlled by structural heterogeneity on and around the plate interface.<br /><br />In addition, the buoyancy force of the slow anomaly can cause a morphological response from the subducting slab, thus increasing the shear stress on the plate interface. Thermal conduction or thermo-mechanical erosion from the slow anomaly may result in transformation of the interface rheology from frictional to viscous shear.<br /><br />This transformation may partly account for the occurrence of slow-slip earthquakes above slow anomalies. The slow-slip area can impede rupture propagation and host afterslip of a giant megathrust earthquake.<br /><br />"It's necessary to conduct seismic tomography to investigate more detailed asthenospheric structures beneath a subducting slab, which may pinpoint the potential location of a future giant megathrust earthquake," said Dr. Fan.</p><p><br /><i><u>The above story is based on <a href="https://www.nature.com/articles/s41561-021-00728-x" rel="nofollow" target="_blank">materials </a>provided by<a href="https://english.cas.cn/" rel="nofollow" target="_blank"> Chinese Academy of Sciences.</a></u></i><br /> <br /></p>

How Do Slow Anomalies Beneath Subducting Slabs Affect Giant Megathrust Earthquakes?

    Earthquakes and volcanoes in subduction zones may cause great human catastrophe. Previous studies on subduction zone structure and causa...

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Earth’s Continental Crust Emerged 500 Million Years Earlier Than Thought

<p><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/-jqtA4AaiE0U/YIdqNQc7aWI/AAAAAAAAS9Q/H4Yev3TjH3QW0AJJpQOZD0Z9wzymtkC4gCLcBGAsYHQ/s1145/Earth%25E2%2580%2599s%2BContinental%2BCrust%2BEmerged%2B500%2BMillion%2BYears%2BEarlier%2BThan%2BThought%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="688" data-original-width="1145" height="384" src="https://1.bp.blogspot.com/-jqtA4AaiE0U/YIdqNQc7aWI/AAAAAAAAS9Q/H4Yev3TjH3QW0AJJpQOZD0Z9wzymtkC4gCLcBGAsYHQ/w640-h384/Earth%25E2%2580%2599s%2BContinental%2BCrust%2BEmerged%2B500%2BMillion%2BYears%2BEarlier%2BThan%2BThought%2B%25281%2529.jpg" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">An artist’s conception of the early Earth, showing a surface bombarded by large impacts that result in the extrusion of magma onto the surface. At the same time, distal portions of the planet’s surface may have retained liquid water. Credit: Simone Marchi/SwRI</td></tr></tbody></table> </p><p>The first emergence and persistence of continental crust on Earth during the Archaean (4 billion to 2.5 billion years ago) has important implications for plate tectonics, ocean chemistry, and biological evolution, and it happened about half a billion years earlier than previously thought, according to new research being presented at the EGU General Assembly.<br /><br />Once land becomes established through dynamic processes like plate tectonics, it begins to weather and add crucial minerals and nutrients to the ocean. A record of these nutrients is preserved in the ancient rock record. Previous research used strontium isotopes in marine carbonates, but these rocks are usually scarce or altered in rocks older than 3 billion years.<br /><br />Now, researchers are presenting a new approach to trace the first emergence of old rocks using a different mineral: "barite."<br /><br />Barite forms from a combination of sulfate coming from ocean water mixing with barium from hydrothermal vents. Barite holds a robust record of ocean chemistry within its structure, useful for reconstructing ancient environments. "The composition of the piece of barite we pick up in the field now that has been on Earth for three and a half billion years, is exactly the same as it was when it when it actually precipitated," says Desiree Roerdink, a geochemist at University of Bergen, Norway, and team leader of the new research. "So in essence, it is really a great recorder to look at processes on the early Earth."<br /><br />Roerdink and her team tested six different deposits on three different continents, ranging from about 3.2 billion to 3.5 billion years old. They calculated the ratio of strontium isotopes in the barite, and from there, inferred the time where the weathered continental rock made its way to the ocean and incorporated itself into the barite. Based on the data captured in the barite, they found that weathering started about 3.7 billion years ago -- about 500 million years earlier than previously thought.<br /><br />"That is a huge time period," Roerdink says. "It essentially has implications for the way that we think about how life evolved." She added that scientists usually think about life starting in deep sea, hydrothermal settings, but the biosphere is complex. "We don't really know if it is possible that life could have developed at the same time on land," she noted, adding "but then that land has to be there."<br /><br />Lastly, the emergence of land says something about plate tectonics and the early emergence of a geodynamic Earth. "To get land, you need processes operating to form that continental crust, and form a crust that is chemically different from the oceanic crust," Roerdink says.</p><p> </p><p><i><u><span style="font-family: trebuchet;">The above story is based on <a href="https://www.egu.eu/news/843/new-research-uncovers-continental-crust-emerged-500-million-years-earlier-than-previously-thought/" 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;"><span> </span>provided by<span> </span></span><a href="http://www.egu.eu/" 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"><strong style="border-radius: 0px !important; box-sizing: border-box; font-weight: bold;">European Geosciences Union</strong></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;">.</span></span></u></i> </p>

Earth’s Continental Crust Emerged 500 Million Years Earlier Than Thought

An artist’s conception of the early Earth, showing a surface bombarded by large impacts that result in the extrusion of magma onto the surfa...

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Mysterious Melting of Earth’s Crust in Western North America Investigated by Scientists

<p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-lD_eSxp9z2o/YIOGLdUKwNI/AAAAAAAAS9I/a3U5QuZP-BMgAaCDR0vhUMc4eIG7ksQKgCLcBGAsYHQ/s1202/Mysterious%2BMelting%2Bof%2BEarth%25E2%2580%2599s%2BCrust%2Bin%2BWestern%2BNorth%2BAmerica%2BInvestigated%2Bby%2BScientists%2B%25281%2529.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="768" data-original-width="1202" height="408" src="https://1.bp.blogspot.com/-lD_eSxp9z2o/YIOGLdUKwNI/AAAAAAAAS9I/a3U5QuZP-BMgAaCDR0vhUMc4eIG7ksQKgCLcBGAsYHQ/w640-h408/Mysterious%2BMelting%2Bof%2BEarth%25E2%2580%2599s%2BCrust%2Bin%2BWestern%2BNorth%2BAmerica%2BInvestigated%2Bby%2BScientists%2B%25281%2529.jpg" width="640" /></a></div> <br /><p></p><p>A group of University of Wyoming professors and students has identified an unusual belt of igneous rocks that stretches for over 2,000 miles from British Columbia, Canada, to Sonora, Mexico.<br /><br />The rock belt runs through Idaho, Montana, Nevada, southeast California and Arizona.<br /><br />“Geoscientists usually associate long belts of igneous rocks with chains of volcanoes at subduction zones, like Mount Shasta, Mount Hood, Mount St. Helens and Mount Rainer,” says Jay Chapman, an assistant professor in UW’s Department of Geology and Geophysics. “What makes this finding so interesting and mysterious is that this belt of igneous rocks is located much farther inland, away from the edge of the continent, and doesn’t contain any evidence for producing volcanoes. In fact, all of the melting to generate the igneous rocks originally took place deep underground, five to 10 miles beneath the surface.”<br /><br />Chapman is lead author of a paper, titled “The North American Cordilleran Anatectic Belt,” which was published online in February in the journal Earth-Science Reviews. The print version will be published this month.<br /><br />The paper is a result of a special course taught by Simone Runyon, an assistant professor in UW’s Department of Geology and Geophysics, and Chapman. Runyon, six UW graduate students and one undergraduate student, who took part in the course, are co-authors of the paper.<br /><br />“It was really fascinating to start with a scientific question in a classroom, then collect and analyze data, and eventually publish our results,” says Cody Pridmore, a UW graduate student from Orange, Calif., and co-author of the paper. “It’s a process most college students don’t get to experience.”<br /><br />One clue to the origin of the belt of igneous rocks is that the rocks chiefly formed 80 million to 50 million years ago, during a mountain-building event called the Laramide orogeny.<br /><br />“The Laramide orogeny created most of the major mountain ranges we have in Wyoming, and the name actually comes from the Laramie Range,” Chapman says. “Although there are no igneous rocks of this type and age present in those mountains, we suspect that the tectonic processes that created the mountains also contributed to melting Earth’s crust.”<br /><br />The researchers have several working hypotheses about what caused the rocks to melt. One hypothesis is that water infiltrated the deep crust.<br /><br />“The geochemistry of these rocks indicates that melting may have occurred at relatively low temperatures, below 800 degrees Celsius,” says Jessie Shields, a Ph.D. student at UW from Minneapolis, Minn., who is working to solve this mystery. “That is still very hot, but not hot enough to produce very large volumes of magma. Water lowers the melting point of rocks, similar to how salt lowers the melting point of ice, and could increase the amount of magma generated.”<br /><br />This work has implications for what causes rocks to melt and where specific types of magmas can be found.<br /><br />“Many of the igneous systems in the study area contain economically important ore deposits,” says Runyon, who specializes in ore deposits. “Understanding the large-scale igneous processes that form these provinces helps us to better understand how ore deposits form and to better explore for natural resources.”<br /><br />The research project is a joint effort involving UW; Andy Barth, a professor at Indiana University-Purdue University Indianapolis; and Gordon Haxel, a U.S. Geological Survey scientist based in Flagstaff, Ariz. Other UW students involved were graduate students Brandi Lawler, of Gordon, Wisc.; Shane Scoggin, of Reston, Va.; Nathan Swaim, of Monument, Colo.; and Adam Trzinski, of Manteno, Ill.; and undergraduate Hannah Wiley, of Sheridan.</p><p> <br /><i><u>The above story is based on <a href="http://www.uwyo.edu/uw/news/2021/04/uw-scientists-probe-mysterious-melting-of-earths-crust-in-western-north-america.html" rel="nofollow" target="_blank">materials </a>provided by <a href="http://www.uwyo.edu/" rel="nofollow" target="_blank">University of Wyoming.</a></u></i><br /></p>

Mysterious Melting of Earth’s Crust in Western North America Investigated by Scientists

  A group of University of Wyoming professors and students has identified an unusual belt of igneous rocks that stretches for over 2,000 mil...

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The Colorful Charm of Ametrine

<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/-OdR3RfcAKxI/YHV65_Z2WBI/AAAAAAAAS8c/8FfaoPO3b_4yL6zYCxpAIzksAOeVujC4QCLcBGAsYHQ/s1272/7511cdce7c41df3916a7a1edd7ed1768.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="824" data-original-width="1272" height="414" src="https://1.bp.blogspot.com/-OdR3RfcAKxI/YHV65_Z2WBI/AAAAAAAAS8c/8FfaoPO3b_4yL6zYCxpAIzksAOeVujC4QCLcBGAsYHQ/w640-h414/7511cdce7c41df3916a7a1edd7ed1768.jpg" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"> Rough Ametrine. credit: GoldenHourMinerals<br /></td></tr></tbody></table><br /><p>A bicolor variety of quartz that is purple amethyst on one side and orange citrine on the other, ametrine occurs naturally only at the Anahí Mine in the Sandoval Province of eastern Bolivia.<br /><br />Ametrine is composed of silicon dioxide (SiO₂ ) and it is a tectosilicate, which means it has a silicate framework linked together through shared oxygen atoms.<br /><br />Ametrine is a mix of both Ametrine and Citrine producing a mixture of purple and yellow/orange crystal colours. It is produced under such exceptional and improbable conditions, requiring a perfect combination of iron presence and differing temperatures within a very confined area, that it has occurred only once that we know of, in only one known place in the world: Santa Cruz, Bolivia. </p><p>The Anahí mine is the one and only bolivianite mine known to exist anywhere on Earth. The mineralization is found in the northern part of a hill formed by limestones and dolomites, and has been generated by silicification of the limestones belonging to the Murcielago Group, deposited in the Precambrian, between 500 and 900 million years ago. Ametrine crystals are found in hydrothermal breccias.<br /><br />The Anahi ametrine crystals range in size from 10 to 30 cm in length and 4 to 12 cm in diameter. When sliced and polished, the interior of the crystals show the typical color zoning. The amethyst and citrine zones run from top to bottom, parallel to the crystal’s c-axis.<br /><br />Ametrine in the low price segment may stem from synthetic material. Green-yellow or golden-blue ametrine does not exist naturally. This gem only exists in Bolivia, it comes from the Ricón del Tigre area, from the Anahí mine.<br /><br /></p>

The Colorful Charm of Ametrine

 Rough Ametrine. credit: GoldenHourMinerals A bicolor variety of quartz that is purple amethyst on one side and orange citrine on the other,...

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How Could Surface Minerals Get in Diamonds Found in The Deepest Depths of The Earth?

<p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-3yFwtU27r-Y/YG3m8Q4g4KI/AAAAAAAAS8M/NiClbK81YwMWjjb7p91rk0pQg3up4XkLACLcBGAsYHQ/s1280/diamond_with_inclusion%2B%25281%2529.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="842" data-original-width="1280" height="420" src="https://1.bp.blogspot.com/-3yFwtU27r-Y/YG3m8Q4g4KI/AAAAAAAAS8M/NiClbK81YwMWjjb7p91rk0pQg3up4XkLACLcBGAsYHQ/w640-h420/diamond_with_inclusion%2B%25281%2529.jpg" width="640" /></a></div> <br /><p></p><p><span style="font-family: georgia;">Diamonds that formed hundreds of kilometers deep below Earth's surface contain traces of chemical reactions that took place on the bottom of the ocean.</span><br /></p><p>Diamonds that formed deep in the Earth's mantle contain evidence of chemical reactions that occurred on the seafloor. Probing these gems can help geoscientists understand how material is exchanged between the planet's surface and its depths.<br /><br />New work published in Science Advances confirms that serpentinite -- a rock that forms from peridotite, the main rock type in Earth's mantle, when water penetrates cracks in the ocean floor -- can carry surface water as far as 700 kilometers deep by plate tectonic processes.<br /><br />"Nearly all tectonic plates that make up the seafloor eventually bend and slide down into the mantle -- a process called subduction, which has the potential to recycle surface materials, such as water, into the Earth," explained Carnegie's Peng Ni, who co-led the research effort with Evan Smith of the Gemological Institute of America.<br /><br />Serpentinite residing inside subducting plates may be one of the most significant, yet poorly known, geochemical pathways by which surface materials are captured and conveyed into the Earth's depths. The presence of deeply-subducted serpentinites was previously suspected -- due to Carnegie and GIA research about the origin of blue diamonds and to the chemical composition of erupted mantle material that makes up mid-ocean ridges, seamounts, and ocean islands. But evidence demonstrating this pathway had not been fully confirmed until now.<br /><br />The research team -- which also included Carnegie's Steven Shirey, and Anat Shahar, as well as GIA's Wuyi Wang and Stephen Richardson of the University of Cape Town -- found physical evidence to confirm this suspicion by studying a type of large diamonds that originate deep inside the planet.<br /><br />"Some of the most famous diamonds in the world fall into this special category of relatively large and pure gem diamonds, such as the world-famous Cullinan," Smith said. "They form between 360 and 750 kilometers down, at least as deep as the transition zone between the upper and lower mantle."<br /><br />Sometimes they contain inclusions of tiny minerals trapped during diamond crystallization that provide a glimpse into what is happening at these extreme depths.<br /><br />"Studying small samples of minerals formed during deep diamond crystallization can teach us so much about the composition and dynamics of the mantle, because diamond protects the minerals from additional changes on their path to the surface," Shirey explained.<br /><br />In this instance, the researchers were able to analyze the isotopic composition of iron in the metallic inclusions. Like other elements, iron can have different numbers of neutrons in its nucleus, which gives rise to iron atoms of slightly different mass, or different "isotopes" of iron. Measuring the ratios of "heavy" and "light" iron isotopes gives scientists a sort of fingerprint of the iron.<br /><br />The diamond inclusions studied by the team had a higher ratio of heavy to light iron isotopes than typically found in most mantle minerals. This indicates that they probably didn't originate from deep-Earth geochemical processes. Instead, it points to magnetite and other iron-rich minerals formed when oceanic plate peridotite transformed to serpentinite on the seafloor. This hydrated rock was eventually subducted hundreds of kilometers down into the mantle transition zone, where these particular diamonds crystallized.<br /><br />"Our findings confirm a long-suspected pathway for deep-Earth recycling, allowing us to trace how minerals from the surface are drawn down into the mantle and create variability in its composition," Shahar concluded.</p><p> </p><p><span style="font-family: times;"><i><u>The above story is based on <a href="https://carnegiescience.edu/news/deep-diamonds-contain-evidence-deep-earth-recycling-processes" 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;"><span> </span>provided by<span> </span></span><a href="https://carnegiescience.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"><strong style="border-radius: 0px !important; box-sizing: border-box; font-weight: bold;">Carnegie Institution for Science</strong></a></u></i></span><span style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline !important; float: none; font-family: "Helvetica Neue", Helvetica, Arial, sans-serif; font-size: 14px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; 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;"><span style="font-family: times;"><i><u>.</u></i></span><span><span style="font-family: times;"><i><u> </u></i></span><br /></span></span></p>

How Could Surface Minerals Get in Diamonds Found in The Deepest Depths of The Earth?

  Diamonds that formed hundreds of kilometers deep below Earth's surface contain traces of chemical reactions that took place on the bot...

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Scientists Create Crystal Stronger Than Diamond

<p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-IdSF8YDv6kU/YGXqBGf0NaI/AAAAAAAAS7w/FxznrEwQuFIk-qYENQS0FDCPTJ8QfP3AACLcBGAsYHQ/s1245/Scientists%2Bhave%2Bmade%2Ba%2Bdiamond%2Bthat%2527s%2Bharder%2Bthan%2Bdiamond%2B%25281%2529.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="790" data-original-width="1245" height="406" src="https://1.bp.blogspot.com/-IdSF8YDv6kU/YGXqBGf0NaI/AAAAAAAAS7w/FxznrEwQuFIk-qYENQS0FDCPTJ8QfP3AACLcBGAsYHQ/w640-h406/Scientists%2Bhave%2Bmade%2Ba%2Bdiamond%2Bthat%2527s%2Bharder%2Bthan%2Bdiamond%2B%25281%2529.jpg" title="Scientists Create Crystal Stronger Than Diamond" width="640" /></a></div> <br /><p></p><p> Currently, diamond is regarded to be one of the hardest and most scratch-resistant natural materials in the world. Most diamonds found in nature and often used in jewelry display a cubic crystal structure, a repeating pattern of 8 atoms forming a cube with carbon atoms at its vertices. Each carbon atom forms four bonds with its neighbors, explaining the overall stability and hardness of the crystal structure.<br /></p><p>Nature's strongest material now has some stiff competition. For the first time, researchers have hard evidence that human-made hexagonal diamonds are stiffer than the common cubic diamonds found in nature and often used in jewelry.<br /><br />Named for their six-sided crystal structure, hexagonal diamonds have been found at some meteorite impact sites, and others have been made briefly in labs, but these were either too small or had too short of an existence to be measured.<br /><br />Now scientists at Washington State University's Institute for Shock Physics created hexagonal diamonds large enough to measure their stiffness using sound waves. Their findings are detailed in a recent paper in Physical Review B.<br /><br />"Diamond is a very unique material," said Yogendra Gupta, director of the Institute for Shock Physics and corresponding author on the study. "It is not only the strongest -- it has beautiful optical properties and a very high thermal conductivity. Now we have made the hexagonal form of diamond, produced under shock compression experiments, that is significantly stiffer and stronger than regular gem diamonds."<br /><br />Researchers have long wanted to create a material stronger than natural diamonds, which could have a variety of uses in industry. While many theorized that hexagonal diamonds would be stronger, the WSU study provides the first experimental evidence that they are.<br /><br />Lead author Travis Volz, now a post-doctoral researcher at Lawrence Livermore National Laboratory, focused his dissertation work at WSU on the creation of hexagonal diamonds from graphite. For this study, Volz and Gupta used gunpowder and compressed gas to propel small graphite disks about the size of a dime at a speed of around 15,000 miles per hour onto a transparent material. The impact produced shockwaves in the disks that very rapidly transformed them into hexagonal diamonds.<br /><br />Immediately after impact the researchers produced a small sound wave and used lasers to measure its movement through the diamond. Sound moves faster through stiffer material. Previously sound moved fastest through cubic diamond; in the lab-created hexagonal diamonds it moved faster.<br /><br />Each process happened in several billionths of a second, or nanoseconds, but the researchers were able to make the stiffness measurements before the high velocity impact destroyed the diamond.<br /><br />Stiffness is the ability of a material to resist deformation under a force or pressure -- for instance, a rock is stiffer than rubber as rubber will bend when pressed. Hardness is the resistance to scratching or other surface deformations.<br /><br />Generally stiffer materials are also harder, said Volz. While the researchers weren't able to scratch the diamonds to test hardness directly, by measuring the diamonds' stiffness, they can make inferences about their hardness.<br /><br />If the science advances to the point where lab-made hexagonal diamonds can be created and recovered, they could have a range of uses.<br /><br />"Hard materials are useful for machining capabilities," said Volz. "Diamond has been used for a long time in drill bits, for example. Since we found that the hexagonal diamond is likely harder than the cubic diamond, it could be a superior alternative for machining, drilling or any type of application where the cubic diamond is used."<br /><br />While the industrial advantages are clear, Gupta said it is still possible hexagonal diamonds could one day be used on engagement rings. Currently lab-made cubic diamonds have less value compared to their natural peers, but hexagonal diamonds would likely be more novel.<br /><br />"If someday we can produce them and polish them, I think they'd be more in-demand than cubic diamonds," said Gupta. "If somebody said to you, 'look, I'm going to give you the choice of two diamonds: one is lot more rare than the other one.' Which one would you pick?" </p><p><br /></p><p><i><u><span style="font-family: trebuchet;">The above story is based on <a href="https://news.wsu.edu/2021/03/31/lab-made-hexagonal-diamonds-stiffer-natural-diamonds/" 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;"><span> </span>provided by<span> </span></span><a href="http://www.wsu.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"><strong style="border-radius: 0px !important; box-sizing: border-box; font-weight: bold;">Washington State University</strong></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 Sara Zaske.</span></span></u></i></p>

Scientists Create Crystal Stronger Than Diamond

   Currently, diamond is regarded to be one of the hardest and most scratch-resistant natural materials in the world. Most diamonds found in...

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L.A.’s Biggest Quake Threat Sits on Overlooked Part of San Andreas, Study Says

<p><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/-J08hYnthsgo/YF4IzyxflMI/AAAAAAAAS7Q/tFIe5RwuM7QH8-oFGJLA0c_7CRfPIO2-ACLcBGAsYHQ/s1230/Arrows%2Bpointing%2Bto%2Bthe%2BMission%2BCreek%2Bstrand%2Bof%2Bthe%2BSan%2BAndreas%2BFault.%2B%2528Uniform%2BCalifornia%2BEarthquake%2BRupture%2BForecast%2529%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="632" data-original-width="1230" height="328" src="https://1.bp.blogspot.com/-J08hYnthsgo/YF4IzyxflMI/AAAAAAAAS7Q/tFIe5RwuM7QH8-oFGJLA0c_7CRfPIO2-ACLcBGAsYHQ/w640-h328/Arrows%2Bpointing%2Bto%2Bthe%2BMission%2BCreek%2Bstrand%2Bof%2Bthe%2BSan%2BAndreas%2BFault.%2B%2528Uniform%2BCalifornia%2BEarthquake%2BRupture%2BForecast%2529%2B%25281%2529.jpg" title="L.A.’s Biggest Quake Threat Sits on Overlooked Part of San Andreas, Study Says" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Arrows pointing to the Mission Creek strand of the San Andreas Fault. (Uniform California Earthquake Rupture Forecast)</td></tr></tbody></table>  <br /></p><p><span style="font-family: georgia;">Part Of The San Andreas Fault Is Moving Way Faster Than We Previously Thought</span><br /></p><p>Scientists have pinpointed a long-overlooked portion of the southern San Andreas Fault that they say could pose the most significant earthquake risk for the Greater Los Angeles area—and it's about 80 years overdue for release.<br /><br />But there could be a silver lining. If their analysis is right, experts say it's possible that when a long-pre<br />dicted and much more devastating earthquake hits, it may not do quite as much damage to the region as some scientists previously feared.<br /><br />"That's a significant reduction in risk for L.A. if this is true," said longtime seismologist Lucy Jones, who was not involved in the study published Wednesday in the journal Science Advances.<br /><br />The San Andreas Fault is a roughly 800-mile fracture that runs much of the length of California and is capable of producing a much-feared, massive temblor known simply as "the Big One."<br /><br />As the Pacific and North American continental plates move past one another, the southern San Andreas Fault carries about half the resulting strain from that motion, up to 25 millimeters (about 1 inch) per year. Eventually, that strain is released through earthquakes.<br /><br />Not every part of the fault carries that strain equally, though. In Southern California, the San Andreas Fault system is made up of many smaller "strands," and it's difficult for earthquake researchers to identify which parts of the fault system are most at risk of rupture.<br /><br />Case in point: the bouquet of fault strands—Garnet Hill, Banning and Mission Creek—that crosses the Coachella Valley. Scientists long thought much of the southern San Andreas Fault's slip occurred along the Banning strand and the Garnet Hill strand; the Mission Creek strand, they said, didn't take much of the strain at all.<br /><br />But the new findings turn that idea on its head.<br /><br />Kimberly Blisniuk, an earthquake geologist at San Jose State University, went looking for evidence that earthquakes had caused landforms to move across the surface. She found them at Pushawalla Canyon, a site along the Mission Creek strand in the Little San Bernardino Mountains.<br /><br />There, right next to the water-carved canyon, she saw a series of three ancient "beheaded channels"—long depressions in the desert that looked like they were once part of the original canyon before earthquakes shoved them aside.<br /><br />Blisniuk walked the area to get a better look at these telltale signs of ancient rupture. In each of the channels, she and her team dated the ages of rocks and soil.<br /><br />The oldest channel, which lay about 2 kilometers (more than a mile) away from the current canyon, was roughly 80,000 to 95,000 years old. The second, about 1.3 kilometers (less than a mile) away, was about 70,000 years old; and the third beheaded channel, about 0.7 kilometer (less than half a mile) away, was about 25,000 years old.<br /><br />Based on these three landmarks, the researchers calculated that the average slip rate for the Mission Creek strand was about 21.6 millimeters (less than an inch) per year. At that rate, they realized, it accounted for the vast majority of the strain along the southern San Andreas Fault.<br /><br />By contrast, they calculated that the Banning strand had a slip rate of just 2.5 millimeters per year.<br /><br />"I was really excited," said Blisniuk, who said it took years to produce the data needed to make a convincing case that the ancient channels did indeed once connect to Pushawalla Canyon.<br /><br />"The San Andreas Fault is one of the best studied faults in the world, and there's still so much we can do" to better understand it, she said.<br /><br />Because the southern San Andreas Fault is likely to experience ground-rupturing earthquakes at an average rate of one every 215 years or so—and because the last such earth-shaker in the southernmost section took place in 1726—we're about 80 years overdue, Blisniuk said.<br /><br />About 6 to 9 meters of elastic strain have likely accumulated along the fault since the last one, the scientists said—which means that when it finally releases, the ground will likely shift roughly 20 to 30 feet. Whether it takes a single quake, or many of them, to go that distance remains to be seen, Blisniuk said.<br /><br />The discovery "looks like it could be a landmark study," said Thomas Heaton, an emeritus professor of engineering seismology at Caltech who was not involved in the research.<br /><br />Jones, who was not involved in the study, is now retired from the U.S. Geological Survey. But in 2008, she led a group of more than 300 scientists, engineers and other experts to study the potential consequences of the Big One in detail. The result was the ShakeOut Earthquake Scenario, which predicted that a 7.8 magnitude earthquake on the San Andreas Fault could result in more than 1,800 deaths, 50,000 injuries and $200 billion in damage and other losses.<br /><br />The new findings could alter that scenario and make it less grim, Jones said. Here's why: The Big One can only be triggered by a massive rupture on a long stretch of the San Andreas Fault, something on the order of 200 miles. If that rupture ended up traveling along the Banning strand—as the ShakeOut model assumed—its east-west tilt would send energy into the San Bernardino Valley, the San Gabriel Valley and finally into the Los Angeles Basin.<br /><br />But if the rupture were to follow the Mission Creek strand, its more northwesterly orientation would divert some of that energy away from the L.A. Basin, sparing it some of the devastation.<br /><br />Ultimately, Jones said, "This is a piece in an ongoing debate and not yet completely resolved—probably won't be, until we have the earthquake."<br /><br />Heaton agreed.<br /><br />"It would almost be a surprise to me as a scientist if the real earthquake, when it happens, plays out in a way that's really close to what we imagined," he said. "The earth is always surprising us—it's always reminding us that we need some humility in this business." </p><p><br /><u><i>The above post is reprinted from © the Los Angeles Times</i></u><br /></p>

L.A.’s Biggest Quake Threat Sits on Overlooked Part of San Andreas, Study Says

Arrows pointing to the Mission Creek strand of the San Andreas Fault. (Uniform California Earthquake Rupture Forecast)   Part Of The San And...

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New Rock Type Discovered Beneath The Ocean

<p><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/-hcOL2iR5L-8/YFoM5B386jI/AAAAAAAAS6o/ATt7U-XIYXkPyohQg9sfxp_83A232efygCLcBGAsYHQ/s1200/A%2Bmicroscopic%2Bcross-section%2Bof%2Bthe%2Bnewly%2Bdiscovered%2Btype%2Bof%2BbasaltEXP%2B351%2BScience%2BTeam.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="800" data-original-width="1200" height="426" src="https://1.bp.blogspot.com/-hcOL2iR5L-8/YFoM5B386jI/AAAAAAAAS6o/ATt7U-XIYXkPyohQg9sfxp_83A232efygCLcBGAsYHQ/w640-h426/A%2Bmicroscopic%2Bcross-section%2Bof%2Bthe%2Bnewly%2Bdiscovered%2Btype%2Bof%2BbasaltEXP%2B351%2BScience%2BTeam.jpg" title="Picture credit: Exp. 351 Science Team" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">A microscopic cross-section of the newly discovered type of basalt Picture credit: Exp. 351 Science Team<br /></td></tr></tbody></table> <br /></p><p>Geologists have discovered a new type of rock. While drilling deep into the seafloor, a team of scientists found a new form of basalt that’s vastly different from any other on Earth, and the planet hasn’t produced any more of it for millions of years.<br /><br />The discovery suggests that ocean floor eruptions sourced in the Earth's mantle were even hotter and more voluminous than previously thought. Report co-author is Dr Ivan Savov, of Leeds' Institute of Geophysics and Tectonics, in the university's School of Earth and Environment.<br /><br />He said: "In an era when we rightly admire discoveries made through space exploration, our findings show there are still many discoveries still to make on our own planet.<br /><br />"The rocks that we recovered are distinctly different to rocks of this type that we already know about. In fact, they may be as different to Earth's known ocean floor basalts as Earth's basalts are to the Moon's basalts.<br /><br />"Now that we know where and how this rock type is formed, we anticipate that many other rocks that we know were originally formed by ocean floor eruptions will be re-examined and potentially alter our wider understanding of the basalt formation."<br /><br />The newly-discovered basalt is distinct from known rocks in both its chemical and mineral makeup.<br /><br />Its existence was previously not known because no new examples have been formed in millions of years. As a result, the new basalt type lay buried deep beneath sediment at the bottom of the ocean.<br /><br />To find the new rock, the research team, aboard the Research Vessel (RV) JOIDES "Resolution", sank their drilling equipment 6km down to the ocean floor of the Amami Sankaku Basin - about 1,000km southwest of Japan's Mount Fuji volcano.<br /><br />They then drilled a further 1.5km into the ocean floor, extracting samples that had never before been examined by scientists.<br /><br />The research area was part of the birth of the "Ring of Fire" - a horseshoe-shaped belt known for regular volcanic eruptions and earthquakes. It stretches about 40,000 km around the Pacific, and is thought to have begun forming at least 50 million years ago.<br /><br />Dr Savov explained: "This was one of the deepest waters ever to be considered for drilling, using a research vessel specifically designed for such challenging deep sea environments.<br /><br />"Basalt is among the most common type of rock on earth. We were looking for basalt that was formed during early Ring of Fire volcanic eruptions.".<br /><br />The eruptions that created the newly-discovered basalt were very widespread (covering areas the size of western Europe) and occurred in a relatively short geological timescale of between 1-2 million years.</p><p> </p><p><i><u>The above story is based on <a href="http://www.leeds.ac.uk/news/article/4795/new_basalt_type_discovered_beneath_the_ocean" rel="nofollow" target="_blank">materials </a>provided by <a href="http://www.leeds.ac.uk/news/" rel="nofollow" target="_blank">University of Leeds</a>. </u></i><br /></p>

New Rock Type Discovered Beneath The Ocean

A microscopic cross-section of the newly discovered type of basalt Picture credit: Exp. 351 Science Team   Geologists have discovered a new ...

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Here’s What a Metal Volcano Would Look Like

<p></p><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/-wlBPPBYH_KM/YFjIZykgfCI/AAAAAAAAS6Q/zI8bFEVVQncwXh9NBPoNpESoSbiPtIOKwCLcBGAsYHQ/s1362/Here%25E2%2580%2599s%2BWhat%2Ba%2BMetal%2BVolcano%2BWould%2BLook%2BLike%2B%25281%2529.jpg" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="557" data-original-width="1362" height="262" src="https://1.bp.blogspot.com/-wlBPPBYH_KM/YFjIZykgfCI/AAAAAAAAS6Q/zI8bFEVVQncwXh9NBPoNpESoSbiPtIOKwCLcBGAsYHQ/w640-h262/Here%25E2%2580%2599s%2BWhat%2Ba%2BMetal%2BVolcano%2BWould%2BLook%2BLike%2B%25281%2529.jpg" title="Here’s What a Metal Volcano Would Look Like" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;">Metallic lava flow emerging from rocky lava. <b>Credit</b>: Arianna Soldati</span></td></tr></tbody></table> <br /><p></p><p><span style="font-family: georgia;"><span> When Volcanoes Go Metal</span></span></p><p><span style="font-family: georgia;">A team of scientists is hard at work on an important project: Figuring out what a volcano made of metal instead of rock would look like.</span><br /></p><p>What would a volcano -- and its lava flows -- look like on a planetary body made primarily of metal? A pilot study from North Carolina State University offers insights into ferrovolcanism that could help scientists interpret landscape features on other worlds.<br /><br />Volcanoes form when magma, which consists of the partially molten solids beneath a planet's surface, erupts. On Earth, that magma is mostly molten rock, composed largely of silica. But not every planetary body is made of rock -- some can be primarily icy or even metallic.<br /><br />"Cryovolcanism is volcanic activity on icy worlds, and we've seen it happen on Saturn's moon Enceladus," says Arianna Soldati, assistant professor of marine, earth and atmospheric sciences at NC State and lead author of a paper describing the work. "But ferrovolcanism, volcanic activity on metallic worlds, hasn't been observed yet."<br /><br />Enter 16 Psyche, a 140-mile diameter asteroid situated in the asteroid belt between Mars and Jupiter. Its surface, according to infrared and radar observations, is mainly iron and nickel. 16 Psyche is the subject of an upcoming NASA mission, and the asteroid inspired Soldati to think about what volcanic activity might look like on a metallic world.<br /><br />"When we look at images of worlds unlike ours, we still use what happens on Earth -- like evidence of volcanic eruptions -- to interpret them," Soldati says. "However, we don't have widespread metallic volcanism on Earth, so we must imagine what those volcanic processes might look like on other worlds so that we can interpret images correctly."<br /><br />Soldati defines two possible types of ferrovolcanism: Type 1, or pure ferrovolcanism, occurring on entirely metallic bodies; and Type 2, spurious ferrovolcanism, occurring on hybrid rocky-metallic bodies.<br /><br />In a pilot study, Soldati and colleagues from the Syracuse Lava Project produced Type 2 ferrovolcanism, in which metal separates from rock as the magma forms.<br /><br />"The Lava Project's furnace is configured for melting rock, so we were working with the metals (mainly iron) that naturally occur within them," Soldati says. "When you melt rock under the extreme conditions of the furnace, some of the iron will separate out and sink to the bottom since it's heavier. By completely emptying the furnace, we were able to see how that metal magma behaved compared to the rock one."<br /><br />The metallic lava flows travelled 10 times faster and spread more thinly than the rock flows, breaking into a myriad of braided channels. The metal also traveled largely beneath the rock flow, emerging from the leading edge of the rocky lava.<br /><br />The smooth, thin, braided, widely spread layers of metallic lava would leave a very different impression on a planet's surface than the often thick, rough, rocky flows we find on Earth, according to Soldati.<br /><br />"Although this is a pilot project, there are still some things we can say," Soldati says. "If there were volcanoes on 16 Psyche -- or on another metallic body -- they definitely wouldn't look like the steep-sided Mt. Fuji, an iconic terrestrial volcano. Instead, they would probably have gentle slopes and broad cones. That's how an iron volcano would be built -- thin flows that expand over longer distances."</p><p> </p><p><i><u><span style="font-family: trebuchet;">  The above story is based on <a href="https://news.ncsu.edu/2021/03/when-volcanoes-go-metal/" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px; 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; 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;"><span> </span>provided by<span> </span></span><a href="http://www.ncsu.edu/" rel="nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px; 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"><b style="border-radius: 0px; box-sizing: border-box; font-weight: bold;">North Carolina State University</b></a></span></u></i><span face=""Helvetica Neue", Helvetica, Arial, sans-serif" style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline; float: none; font-size: 14px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; 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;"><i><u><span style="font-family: trebuchet;">. Original written by Tracey Peake.</span></u></i><span><i><u><span style="font-family: trebuchet;"> </span></u></i><br /></span></span></p>

Here’s What a Metal Volcano Would Look Like

Metallic lava flow emerging from rocky lava. Credit : Arianna Soldati    When Volcanoes Go Metal A team of scientists is hard at work on an ...

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Geologists Discover Powerful 'River of Rocks' Below Caribbean

<p><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/-Kn81uzRNtZM/YFN9YlwRlEI/AAAAAAAAS58/TvqcalXaqBcLG7dldkDTNYRYI7x7dR_XwCLcBGAsYHQ/s1179/geologistsdi%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="925" data-original-width="1179" height="502" src="https://1.bp.blogspot.com/-Kn81uzRNtZM/YFN9YlwRlEI/AAAAAAAAS58/TvqcalXaqBcLG7dldkDTNYRYI7x7dR_XwCLcBGAsYHQ/w640-h502/geologistsdi%2B%25281%2529.jpg" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;">In this image, the warped amount of the surface is due to the opening of the Central American gateway that allowed hot material to flow through. (a) Before 8.5 million years ago, hot material was upwelling under the Galapagos from deep inside the Earth, but was blocked out of the Caribbean because of a curtain of subducting plate. (b) A gateway opened at 8.5 million years ago allowing the hot material to flow through. (c) Today, the hot material reaches midway between Central America and the Lesser Antilles, tilting up the bottom of the Caribbean sea by about 300 m (1,000 ft). Credit: University of Houston</span></td></tr></tbody></table> <br /></p><p><span style="font-family: georgia;">New findings by the geologists call into question the theory that tectonic plates are driven by the weight of their sinking portions, with an underlying, hot layer serving as no more than a passive lubricant.</span><br /></p><p>Geologists have long thought tectonic plates move because they are pulled by the weight of their sinking portions and that an underlying, hot, softer layer called asthenosphere serves as a passive lubricant. But a team of geologists at the University of Houston has found that layer is actually flowing vigorously, moving fast enough to drive plate motions.<br /><br />In their study published in Nature Communications, researchers from the UH College of Natural Sciences and Mathematics looked at minute changes in satellite-detected gravitational pull within the Caribbean and at mantle tomography images -- similar to a CAT Scan -- of the asthenosphere under the Caribbean. They found a hot "river of rocks" being squeezed from the Pacific Ocean through a gateway under Central America and reaching to the middle of the Caribbean Sea. This underground "river of rocks" started flowing eight million years ago, when the Central American gateway opened, uplifting the overlying seafloor by several hundred feet and tilting it to the northeast toward the Lesser Antilles.<br /><br />"Without the extra support generated by this flow in the asthenosphere, portions of Central America would still be below sea level. The Atlantic and the Pacific Oceans would be connected without a need for the Panama Canal," said study co-author Lorenzo Colli, assistant professor of geophysics, geodynamics and mantle structure in the Department of Earth and Atmospheric Sciences.<br /><br />The findings have implications for understanding the shape of the Earth's surface, of its evolution over time through the appearance and disappearance of shallows seas, low-lying land bridges and the forces that move tectonic plates and cause earthquakes.<br /><br />Another fascinating discovery, according to the researchers, is the asthenosphere is moving six inches per year, which is three times faster than an average plate. It can move independently from the overlying plates and drag them in a different direction.<br /><br />"This challenges the top-down notion that subduction is always the driver," explained Jonny Wu, study co-author and assistant professor of structural geology, tectonics and mantle structure. "Think of the plates moving like an air hockey puck and being lubricated from below. Instead, what we found is the air hockey table is imposing its own currents on the puck that's moving around, creating a bottom-up movement that has not been well recognized, and that's being quantified here."<br /><br /></p><p><br /><i><u><span style="font-family: trebuchet;">The above story is based on <a href="https://uh.edu/news-events/stories/2021/march-2021/03112021-geologists-discover-river-of-rocks-below-caribbean.php" 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;"><span> </span>provided by<span> </span></span><a href="http://www.uh.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"><strong style="border-radius: 0px !important; box-sizing: border-box; font-weight: bold;">University of Houston</strong></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 Sara Tubbs.</span></span></u></i></p>

Geologists Discover Powerful 'River of Rocks' Below Caribbean

In this image, the warped amount of the surface is due to the opening of the Central American gateway that allowed hot material to flow thro...

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47-Million-Year-Old Fly Found With a Full Belly

<p><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/-YPetEyVWjFU/YE-QLT6oTYI/AAAAAAAAS5s/PXFrhqYVKf4HHoDuqC0ngX5gCO-j-SJBQCLcBGAsYHQ/s817/47%2Bmillion%2Byear%2Bold%2Bfly%2Bfound%2Bwith%2Ba%2Bfull%2Bbelly%2B%25283%2529%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="467" data-original-width="817" height="366" src="https://1.bp.blogspot.com/-YPetEyVWjFU/YE-QLT6oTYI/AAAAAAAAS5s/PXFrhqYVKf4HHoDuqC0ngX5gCO-j-SJBQCLcBGAsYHQ/w640-h366/47%2Bmillion%2Byear%2Bold%2Bfly%2Bfound%2Bwith%2Ba%2Bfull%2Bbelly%2B%25283%2529%2B%25281%2529.jpg" title="47 million year old fly found with a full belly (2)" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">A 47-million-year old fossil belonging to a previously unknown species of fly was found at the Messel Pit in central Germany<br /></td></tr></tbody></table> <br /></p><p>For The First Time, We've Examined The Stomach Contents of a 47-Million-Year-Old Fly <br /></p><p> Scientists have found a 47-million-year-old fossilized fly with a bloated belly absolutely full of pollen.<br /><br />The discovery is the first direct evidence that some species of ancient tangle-veined flies once fed on the microspores of several different species of subtropical plant.</p><p>It was not the fly itself that caught the scientists' attention, but its bulging abdomen suggesting it was still full with the fly's last food intake. Surprisingly, analysis of the stomach content revealed it was full with pollen from different plants. The fossil pollen from the fly's stomach was used to reconstruct the ancient environment inhabited by the fly, the biotic interactions between plant and fly, and the fly's behaviour during feeding.<br /></p><h4 style="text-align: left;">Flies as pollinators</h4><p>Today, bees, butterflies and bumblebees are the typical pollinators, which are also known to feed on pollen. That flies also play an important role in pollination is rarely addressed. "The rich pollen content we discovered in the fly's stomach suggests that flies were already feeding and transporting pollen 47 million years ago and shows it played an important role in the pollen dispersal of several plant taxa," says Fridgeir Grímsson from the Department of Botany and Biodiversity Research of the University of Vienna. "Flies were major pollinators in ancient (sub-)tropical equivalent ecosystems and might even have outshined the bees," the scientist concludes.<br /></p><h4 style="text-align: left;">Short-distance flights for food</h4><p>The extracted pollen was dominated by grains of Decodon (waterwillow) and Parthenocissus (virgin ivy). Today, the waterwillow is a sub-shrub growing in wetlands and the shallows of lakes, suggesting open low canopy habitat. The co-dominance of virgin ivy also suggests that the fly fed on plants growing at the forest margin surrounding the ancient Messel lake. "It is likely that the fly avoided long-distance flights between food sources and sought pollen from closely associated plants," says Grímsson. </p><p><br /></p><p><i><u><span style="font-family: trebuchet;">The above story is based on <a href="https://medienportal.univie.ac.at/presse/aktuelle-pressemeldungen/detailansicht/artikel/fossilized-feeding-frenzy-47-million-year-old-fly-found-with-a-full-belly/" 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;"><span> </span>provided by<span> </span></span><a href="http://www.univie.ac.at/en/" 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"><strong style="border-radius: 0px !important; box-sizing: border-box; font-weight: bold;">University of Vienna</strong></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;">.</span></span></u></i></p>

47-Million-Year-Old Fly Found With a Full Belly

A 47-million-year old fossil belonging to a previously unknown species of fly was found at the Messel Pit in central Germany   For The First...

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Rock Rising From Below the Atlantic May Drive Continents Apart

<p><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/-GaZ98hBVNSI/YE4xSfKKYGI/AAAAAAAAS5k/Hfr_lzqpkw4dChGcMi0gOZuPW1hkuXP6QCLcBGAsYHQ/s1224/Rock%2BRising%2BFrom%2BBelow%2Bthe%2BAtlantic%2BMay%2BDrive%2BContinents%2BApart.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="689" data-original-width="1224" height="360" src="https://1.bp.blogspot.com/-GaZ98hBVNSI/YE4xSfKKYGI/AAAAAAAAS5k/Hfr_lzqpkw4dChGcMi0gOZuPW1hkuXP6QCLcBGAsYHQ/w640-h360/Rock%2BRising%2BFrom%2BBelow%2Bthe%2BAtlantic%2BMay%2BDrive%2BContinents%2BApart.jpg" title="Rock Rising From Below the Atlantic May Drive Continents Apart" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Material rising from deep below the Mid-Atlantic Ridge may widen the ocean by a few centimeters every year. The ridge is visible in this false-color map as a light blue line through the Atlantic.<br /></td></tr></tbody></table> <br /></p><p> Hot rock surging from deep beneath the Atlantic Ocean may be driving the continents on either side apart. That’s the finding of a new study.<br /></p><p>An upsurge of matter from deep beneath the Earth's crust could be pushing the continents of North and South America further apart from Europe and Africa, new research has found.<br /><br />The plates attached to the Americas are moving apart from those attached to Europe and Africa by four centimetres per year. In between these continents lies the Mid-Atlantic Ridge, a site where new plates are formed and a dividing line between plates moving to the west and those moving to the east; beneath this ridge, material rises to replace the space left by the plates as they move apart.<br /><br />Conventional wisdom is that this process is normally driven by distant gravity forces as denser parts of the plates sink back into the Earth. However, the driving force behind the separation of the Atlantic plates has remained a mystery because the Atlantic ocean is not surrounded by dense, sinking plates.<br /><br />Now a team of seismologists, led by the University of Southampton, have found evidence of an upwelling in the mantle -- the material between the Earth's crust and its core -- from depths of more than 600 kilometres beneath the Mid Atlantic ridge, which could be pushing the plates from below, causing the continents to move further apart.<br /><br />Upwellings beneath ridges are typically thought to originate from much shallower depths of around 60 km.<br /><br />The findings, published in the journal Nature provide a greater understanding of plate tectonics which causes many natural disasters around the world, including earthquakes, tsunamis and volcanic eruptions.<br /><br />Over two research cruises on the RV Langseth and RRV Discovery, the team deployed 39 seismometers at the bottom of the Atlantic as part of the PI-LAB (Passive Imaging of the Lithosphere-Asthenosphere Boundary) experiment and EURO-LAB (Experiment to Unearth the Rheological Oceanic Lithosphere-Asthenosphere Boundary). The data provides the first large scale and high-resolution imaging of the mantle beneath the Mid-Atlantic Ridge.<br /><br />This is one of only a few experiments of this scale ever conducted in the oceans and allowed the team to image variations in the structure of the Earth's mantle near depths of 410 km and 660 km -- depths that are associated with abrupt changes in mineral phases. The observed signal was indicative of a deep, sluggish and unexpected upwelling from the deeper mantle.<br /><br />Lead author, Matthew Agius, a former post-doctoral fellow at the University of Southampton and currently at Università degli studi Roma Tre said: "This was a memorable mission that took us a total of 10 weeks at sea in the middle of the Atlantic Ocean. The incredible results shed new light in our understanding of how the Earth interior is connected with plate tectonics, with observations not seen before."<br /><br />Dr Kate Rychert and Dr Nick Harmon from the University of Southampton and Professor Mike Kendall from the University of Oxford led the experiment and were the chief scientists on the cruises. The experiment was funded by NERC (Natural Environment Research Council, UK) and the ERC (European Research Council).<br /><br />Dr Harmon said: "There is a growing distance between North America and Europe, and it is not driven by political or philosophical differences -- it is caused by mantle convection!"<br /><br />As well as helping scientists to develop better models and warning systems for natural disasters, plate tectonics also has an impact on sea levels, and therefore affects climate change estimates over geologic times scales.<br /><br />Dr Rychert said: "This was completely unexpected. It has broad implications for our understanding of Earth's evolution and habitability. It also demonstrates how crucial it is to gather new data from the oceans. There is so much more to explore!"<br /><br />Professor Mike Kendall added: "This work is exciting and that it refutes long held assumptions that mid-ocean ridges might play a passive role in plate tectonics. It suggests that in places such as the Mid-Atlantic, forces at the ridge play an important role in driving newly-formed plates apart."</p><p> </p><p><u><span style="font-family: trebuchet;"> The above story is based on <a href="https://www.southampton.ac.uk/news/2021/01/atlantic-plate-tectonics.page" 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-style: normal; 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-style: normal; 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;"><span> </span>provided by<span> </span></span><a href="http://www.southampton.ac.uk/" 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-style: normal; 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"><strong style="border-radius: 0px !important; box-sizing: border-box; font-weight: bold;">University of Southampton</strong></a></span></u><span style="-webkit-text-stroke-width: 0px; background-color: white; color: #333333; display: inline !important; float: none; font-family: "Helvetica Neue", Helvetica, Arial, sans-serif; font-size: 14px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; 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;"><u><span style="font-family: trebuchet;">.</span></u><span><u><span style="font-family: trebuchet;"> </span></u><br /></span></span></p>

Rock Rising From Below the Atlantic May Drive Continents Apart

Material rising from deep below the Mid-Atlantic Ridge may widen the ocean by a few centimeters every year. The ridge is visible in this fal...

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4.6-Billion-Year-Old Meteorite Is The Oldest Magmatic Rock Ever Found

<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/-uAtjHFAZkVI/YEpAZo23KcI/AAAAAAAAS5c/pmVaMCv_ickgooPZXohNJfkX7_5oG0bOQCLcBGAsYHQ/s1268/4.6-Billion-Year-Old%2BMeteorite%2BIs%2BThe%2BOldest%2BMagmatic%2BRock%2BEver%2BFound%2B%25281%2529.jpg" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1268" data-original-width="1268" height="640" src="https://1.bp.blogspot.com/-uAtjHFAZkVI/YEpAZo23KcI/AAAAAAAAS5c/pmVaMCv_ickgooPZXohNJfkX7_5oG0bOQCLcBGAsYHQ/w640-h640/4.6-Billion-Year-Old%2BMeteorite%2BIs%2BThe%2BOldest%2BMagmatic%2BRock%2BEver%2BFound%2B%25281%2529.jpg" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-family: times;">The Erg Chech 002 meteorite's large crystals suggest that the rock cooled slowly. </span><br /></td></tr></tbody></table><br /><p>A single meteorite crash-landed in the Sahara Desert in 2020. The 4.6 billion-year-old primeval rock is the oldest known sample that may hint at a distant baby relative of Earth.<br /><br />The first meteorite rocks have been recovered in Gloucestershire after they dropped to the ground from the dazzling fireball that was sighted over the UK and northern Europe at the end of last month.<br /><br />The black space rocks, the largest piece of which weighs nearly 300g and crashed down on a driveway in the Cotswolds town of Winchcombe, have been taken to the Natural History Museum in London for further study.<br /><br />Scientists are particularly excited because the rock, likely to become known as the Winchcombe Meteorite, is made of carbonaceous chondrite, a mixture of minerals and organic compounds including amino acids – the ingredients for life itself.<br /><br />While it is three decades since the last meteorite was recovered from UK soil, never before has this kind of rock been found in Britain. It is believed that only 51 carbonaceous chondrite meteorites have ever been found and identified across the world.<br /><div style="width:100%;margin: 0px auto"> <script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script> <ins class="adsbygoogle" style="display:block; text-align:center;" data-ad-format="fluid" data-ad-layout="in-article" data-ad-client="ca-pub-1021498709184325" data-ad-slot="6157425841"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div><br />The rock, along with more fragments recovered from nearby areas, was located after scientists retraced the flight path of the fireball that ripped into the Earth’s atmosphere with a sonic boom that was heard from Ireland to the Netherlands on Sunday 28 February.<br /><br />Dr Ashley King, a researcher at the Natural History Museum, said it is “exciting for us because more this type of meteorite is incredibly rare but holds important clues about our origins”.<br /><br />The meteorite arrived at the museum in remarkably good condition, the scientists said, comparing it to the quality of samples brought back from space missions.<br /><br />“For somebody who didn’t really have an idea what it actually was, the finder did a fantastic job in collecting it,” he said. “He bagged most of it up really quickly on Monday morning, perhaps less than 12 hours after the actual event. He then kept finding bits in his garden over the next few days.”<br /><br />Experts said that the meteorite could provide unique information about the origins of the Solar System some 4.6 billion years ago, as well as where water and the building blocks of life were first formed.<br /><br />“Meteorites like this are relics from the early Solar System, which means they can tell us what the planets are made of,” said Professor Sara Russell. “But we also we think that meteorites like this may have brought water to the Earth, providing the planet with its oceans.”<br /><br />Shortly after the meteor fell to Earth, the UK Fireball Alliance released imagery and maps charting its likely path and saying objects would most likely be found on the ground in and around Cheltenham. At the same time, the alliance advised interested members of the public not to breach coronavirus lockdown measures in order to go looking for space rocks.<br /><br /></p><u><i><span style="font-family: trebuchet;">The study was <a href="https://www.pnas.org/content/118/11/e2026129118" rel="nofollow" target="_blank">published</a> in PNAS.</span></i></u>

4.6-Billion-Year-Old Meteorite Is The Oldest Magmatic Rock Ever Found

The Erg Chech 002 meteorite's large crystals suggest that the rock cooled slowly. A single meteorite crash-landed in the Sahara Desert i...

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Scientists Detect Signs of a Hidden Structure Inside Earth's Core

<p><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/-w2O3szBIL3U/YED4he1upjI/AAAAAAAAS5A/EofMM5WrYRgqHw-_UOCePRfRHgCf26QDQCLcBGAsYHQ/s1210/Scientists%2BDetect%2BSigns%2Bof%2Ba%2BHidden%2BStructure%2BInside%2BEarth%2527s%2BCore%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="756" data-original-width="1210" height="400" src="https://1.bp.blogspot.com/-w2O3szBIL3U/YED4he1upjI/AAAAAAAAS5A/EofMM5WrYRgqHw-_UOCePRfRHgCf26QDQCLcBGAsYHQ/w640-h400/Scientists%2BDetect%2BSigns%2Bof%2Ba%2BHidden%2BStructure%2BInside%2BEarth%2527s%2BCore%2B%25281%2529.jpg" title="Scientists Detect Signs of a Hidden Structure Inside Earth's Core" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">There's probably a fifth layer. (forplayday/iStock/Getty Images)<br /></td></tr></tbody></table> <br /></p><p>It may be time to rewrite the textbooks, as scientists have discovered the Earth has a 'fifth layer' in the form of an innermost inner core at the centre of the planet.</p><p>It's an idea worthy of a Jules Verne novel; a mysterious layer at the centre of our planet. <br /><br />Now researchers from The Australian National University (ANU) have confirmed the existence of the Earth's "innermost inner core".  <br /><br />Lead author of the study, PhD researcher Joanne Stephenson, says while this new layer is difficult to observe, its distinct properties may point to an unknown, dramatic event in the Earth's history. <br /><br />"We found evidence that may indicate a change in the structure of iron, which suggests perhaps two separate cooling events in Earth's history," Ms Stephenson said.  <br /><br />"The details of this big event are still a bit of a mystery, but we've added another piece of the puzzle when it comes to our knowledge of the Earths' inner core." <br /><br />Ms Stephenson says that investigating the structure of the inner core can help us understand more about the Earth's history and evolution.  <br /><br />"Traditionally we've been taught the Earth has four main layers: the crust, the mantle, the outer core and the inner core.  <br /><br />"The idea of another distinct layer was proposed a couple of decades ago, but the data has been very unclear. <br /><br />"We got around this by using a very clever search algorithm to trawl through thousands of the models of the inner core.  <br /><br />"It's very exciting - and might mean we have to re-write the textbooks!"  <br /> <br />For the very least, Verne's famous novel may need a couple of extra pages.  <br /><br />'The details of this big event are still a bit of a mystery, but we've added another piece of the puzzle when it comes to our knowledge of the Earths' inner core,' explained Stephenson.   <br /><br />Until recently our understanding of the deepest depths of our world have been through a combination of volcanic eruptions and seismic waves.<br /><br />They are indirect observations but allowed geologists to determine that the inner core reaches temperatures of more than 5,000 degrees Celsius.<br /><br />The inner core is also relatively small, making up just 1% of the Earth's volume and existing as a single body, with the outer core surrounding it, mantle surrounding that and the crust surrounding the mantle.<br /><br />The structure of Earthʼs deep inner core has important implications for core evolution, since it is thought to be related to the early stages of core formation.</p><p> The research has been published in the Journal of Geophysical Research: Solid Earth. </p><p><u><i><span style="font-family: trebuchet;">The above story is based on <a href="https://www.anu.edu.au/news/all-news/scientists-dig-deep-to-reveal-earth%E2%80%99s-hidden-layer" rel="nofollow" target="_blank">materials </a>provided by <a href="https://www.anu.edu.au/" rel="nofollow" target="_blank">The Australian National University.</a></span></i></u><br /></p>

Scientists Detect Signs of a Hidden Structure Inside Earth's Core

There's probably a fifth layer. (forplayday/iStock/Getty Images)   It may be time to rewrite the textbooks, as scientists have discovere...

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Petrified Tree Up to 20 Million Years Old Found Intact in Lesbos

<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/-DV9FFV5uNgI/YDvGtqadl7I/AAAAAAAAS4c/Kb03THJaYgoHx7WNOuz2dZK3XpmSJ_IFQCLcBGAsYHQ/s1200/Petrified%2BTree%2BUp%2Bto%2B20%2BMillion%2BYears%2BOld%2BFound%2BIntact%2Bin%2BLesbos%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="675" data-original-width="1200" height="360" src="https://1.bp.blogspot.com/-DV9FFV5uNgI/YDvGtqadl7I/AAAAAAAAS4c/Kb03THJaYgoHx7WNOuz2dZK3XpmSJ_IFQCLcBGAsYHQ/w640-h360/Petrified%2BTree%2BUp%2Bto%2B20%2BMillion%2BYears%2BOld%2BFound%2BIntact%2Bin%2BLesbos%2B%25281%2529.jpg" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">A fossilised tree trunk in the petrified forest of Lesbos. Photograph: Nikolas Zouros<br /></td></tr></tbody></table><br /><p>Discovery of 19.5-metre tree with roots, branches and leaves is unprecedented, say experts<br /><br />Greek scientists on the volcanic island of Lesbos say they have found a rare fossilized tree whose branches and roots are still intact after 20 million years.<br /><br />The tree was found during roadwork near an ancient forest petrified millions of years ago on the eastern Mediterranean island and transported from the site using a special splint and metal platform.<br /><br />It is the first time a tree has been found in such good condition complete with branches and roots since excavations began in 1995, said Professor Nikos Zouros of the Museum of Natural History of the Petrified Forest of Lesbos.<br /><br />“It is a unique find,” he said. “[It] is preserved in excellent condition and from studying the fossilized wood we will be able to identify the type of plant it comes from.”<br /><br />Lesbos’ petrified forest, a 15,000-hectare, UNESCO-protected site, is the result of a volcanic eruption 20 million years ago which smothered the island’s then subtropical forest ecosystem in lava.<br /><br />The fossilized tree, about 19 metres long, was preserved by a thick layer of volcanic ash after it fell. A large number of fruit tree leaves were found in the same spot, adding to the picture along with animal bones from the general area.<br /><br />“During the excavations the various forests that existed between 17 and 20 million years ago on Lesbos are being uncovered and we can reconstruct the ecosystem that existed during that period,” said Zouros.</p><p>Excavations by his 35-strong team along a 20km highway connecting Sigri with Kalloni, the region’s biggest town, since 2013 have yielded more than 15 significant fossil sites but the earlier finds have paled next to the most recent.<br /><br />The discovery of an entire tree lying on a bed of leaves was not only unprecedented but down to pure luck. “Constructors were about to asphalt that part of the highway when one of our technicians noticed a tiny branch. The road work stopped, we starting excavating and quite quickly realised we had chanced upon an incredible find,” said Zouros. “It will now form part of the open-air museum we intend to create.”<br /><br />Geologists around the world have described the find as a breakthrough. “We have a case of extraordinary fossilisation in which a tree was preserved with its various parts intact. In the history of paleontology, worldwide, it’s unique,” said the Portuguese palaeontologist Artur Abreu Sá. “That it was buried by sediments expelled during a destructive volcanic eruption, and then found in situ, makes it even more unusual.”<br /><br />The climate emergency has highlighted the need to understand ecosystems in a hotter future if global temperatures are not reduced and, as such, Lesbos’s petrified forest offers an invaluable window into the past, said Prof Iain Stewart, who directs the Sustainable Earth Institute at the University of Plymouth.<br /><br />“It’s a world-class place to look at the type of environment that existed 20m years ago,” he told the Guardian. “Finds like these are a window into a particular past, a greenhouse, hothouse world, that existed back then. They might be an indication of what is coming if we don’t get our act together in tackling the climate change emergency.”<br /><br />In more recent times, Lesbos has been better known for the thousands of refugees who have landed on its shores but the island’s unusually diverse landscape and vegetation also draws scientists interested in its geological past.<br /><br />“The petrified forest is the first stop on our fieldtrip,” said Chronis Tzedakis, a professor of physical geography at University College London, who has been running field classes on the Aegean isle for the past decade. “It never disappoints … These new finds are stunning. The tree with its branches still attached is a rarity, while 150 trunks recovered together will provide a snapshot of a forest community which will allow us to assess its biodiversity at one point in time.”<br /><br />It was in Lesbos that Aristotle worked on the zoological studies that would become the canon of biological thought for the next 2,000 years.<br /><br />Tzedakis has found himself pondering whether the philosopher who was invited to the island by his disciple, Theophrastus, was ultimately influenced by the geological wonder. The polymath, himself a student of Plato, spent two years there, much of it ensconced in the study of marine biology.<br /><br />“I often like to think that Aristotle, who established the foundation of scientific inquiry while on Lesbos must have seen the petrified trees of Sigri,” he said adding that the similarity of some of the fossils to their living relatives may have inspired his theory of species being fixed and well-defined.<br /><br />“Having grown up in nearby Eressos, Theophrastus, the ‘father of botany’, would have surely known about it and have taken the great man to see it.” <br /></p>

Petrified Tree Up to 20 Million Years Old Found Intact in Lesbos

A fossilised tree trunk in the petrified forest of Lesbos. Photograph: Nikolas Zouros Discovery of 19.5-metre tree with roots, branches and ...

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Earth's Magnetic Field Flipped 42,000 Years Ago. The Consequences Were Dramatic

<p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-n94HcCtelLs/YDUocPeQuwI/AAAAAAAAS34/CqdHC0bKI_8K3pjOyGugGmT_Hopp9StbQCLcBGAsYHQ/s1200/Earth%2527s%2BMagnetic%2BField%2BFlipped%2B42%252C000%2BYears%2BAgo.%2BThe%2BConsequences%2BWere%2BDramatic%2B%25282%2529.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="900" data-original-width="1200" height="480" src="https://1.bp.blogspot.com/-n94HcCtelLs/YDUocPeQuwI/AAAAAAAAS34/CqdHC0bKI_8K3pjOyGugGmT_Hopp9StbQCLcBGAsYHQ/w640-h480/Earth%2527s%2BMagnetic%2BField%2BFlipped%2B42%252C000%2BYears%2BAgo.%2BThe%2BConsequences%2BWere%2BDramatic%2B%25282%2529.jpg" width="640" /></a></div> <br /><p></p><p><br />A global period of upheaval 42,000 years ago was the result of a reversal in Earth's magnetic field, new research has found.<br /><br />According to radiocarbon preserved in ancient tree rings, several centuries' worth of climate breakdown, mass extinctions, and even changes in human behaviour can be directly linked to the last time Earth's magnetic field changed its polarity.<br /><br />The research team has named the period the Adams Transitional Geomagnetic Event, or Adams Event, after sci-fi writer Douglas Adams, who famously declared the number 42 the ultimate answer to life, the Universe, and everything.<br /><br />"For the first time ever, we have been able to precisely date the timing and environmental impacts of the last magnetic pole switch," said Earth scientist Chris Turney of the University of New South Wales in Australia. <br /><br />"The findings were made possible with ancient New Zealand kauri trees, which have been preserved in sediments for over 40,000 years. Using the ancient trees we could measure, and date, the spike in atmospheric radiocarbon levels caused by the collapse of Earth's magnetic field."<br /><br />This most recent period of magnetic reversal is known as the Laschamp event, and it is what we call a geomagnetic excursion. This is when the planet's magnetic poles briefly swap places before returning to their original positions. It's one of the most well studied of Earth's magnetic field events, recorded by ferromagnetic minerals.<br /><br />It took place around 41,000 years ago, and lasted for around 800 years. Exactly what impact this event had on life on the planet was unclear, though - so when scientists uncovered an ancient kauri tree (Agathis australis) in 2019 that had been alive during this time period, they seized on the chance to learn more.<br /><br />That's because trees record atmospheric activity in their annual growth rings. In particular, carbon-14, or radiocarbon, can reveal a lot of information about celestial activity.<br /><br />Radiocarbon only occurs on Earth in trace amounts compared to the other naturally occurring carbon isotopes. It's formed in the upper atmosphere under the bombardment of cosmic rays from space. When these rays enter the atmosphere, they interact with the local nitrogen atoms to trigger a nuclear reaction that produces radiocarbon.<br /><br />Since cosmic rays are constantly streaming through space, Earth receives a more or less steady supply of radiocarbon. Therefore, a spike in radiocarbon in tree rings tells us that Earth had greater exposure to radiocarbon during that year.<br /><br />When Earth's magnetic field is weakened, as it was during the Laschamp event, more cosmic rays penetrate through to the atmosphere to produce more radiocarbon. Because of this, scientists had previously been able to ascertain that Earth's magnetic field had weakened to about 28 percent of its normal strength during that 800-year period.<br /><br />The kauri tree, however, allowed the research team to study the years leading up to the Laschamp event. They found that the Adams event took place from about 42,200 years ago, and the magnetic field was at its weakest point before the Laschamp event.<br /><br />"Earth's magnetic field dropped to only 0-6 percent strength during the Adams Event," Turney explained. "We essentially had no magnetic field at all - our cosmic radiation shield was totally gone."<br /><br />During this time, the Sun's magnetic field would also have weakened several times, as it, too, experienced magnetic reversal as part of its regular cycle. These periods see less sunspot and flare activity, but the Sun's magnetic field also provides Earth with a measure of protection from cosmic rays - so, during these solar minima, cosmic ray bombardment would have increased again.<br /><br />This weakened magnetic field would have triggered substantial changes in Earth's atmospheric ozone, with dramatic consequences, including electrical storms and spectacular aurorae, and climate change around the world.<br /><br />"Unfiltered radiation from space ripped apart air particles in Earth's atmosphere, separating electrons and emitting light - a process called ionisation," Turney said.<br /><br />"The ionised air 'fried' the ozone layer, triggering a ripple of climate change across the globe."<br /><br />This is consistent with climate and environmental changes from this time observed in other records from across the globe, such as the mysterious extinction of Australia's megafauna.<br /><br /></p><br /><u><i><span style="font-family: trebuchet;"> The research has been published in <a href="https://science.sciencemag.org/content/371/6531/811" rel="nofollow" target="_blank">Science</a>.</span></i></u>

Earth's Magnetic Field Flipped 42,000 Years Ago. The Consequences Were Dramatic

  A global period of upheaval 42,000 years ago was the result of a reversal in Earth's magnetic field, new research has found. According...

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World's Oldest DNA Found in Siberian Mammoth Teeth

<p><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/-AJb7HQbNAH4/YDKRqjam1NI/AAAAAAAAS3M/NLFLnfm0wDcPos0Run4murd0jsGYzc0TwCLcBGAsYHQ/s1220/World%2527s%2BOldest%2BDNA%2BFound%2Bin%2BSiberian%2BMammoth%2BTeeth%2B%25281%2529.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="871" data-original-width="1220" height="456" src="https://1.bp.blogspot.com/-AJb7HQbNAH4/YDKRqjam1NI/AAAAAAAAS3M/NLFLnfm0wDcPos0Run4murd0jsGYzc0TwCLcBGAsYHQ/w640-h456/World%2527s%2BOldest%2BDNA%2BFound%2Bin%2BSiberian%2BMammoth%2BTeeth%2B%25281%2529.jpg" title="World's Oldest DNA Found in Siberian Mammoth Teeth" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">An illustration of the mammoth.</td></tr></tbody></table> <br /></p><p>Scientists have recovered DNA from mammoth fossils found in Siberian permafrost that are more than a million years old. This DNA—the oldest genomic evidence recovered to date—illuminates the evolutionary history of woolly mammoths and Columbian mammoths. It also raises the prospect of recovering DNA from other organisms this ancient—including extinct members of the human family.<br /><br />Ever since the recovery of two short DNA sequences from a recently extinct zebra subspecies known as the quagga in 1984, researchers have been working to get ever larger amounts of DNA from ever older remains. Advances in ancient DNA extraction and sequencing methods eventually brought to light genomes of creatures from deeper time, including cave bears and Neandertals. </p><p>In 2013, investigators announced that they had retrieved DNA from a 700,000-year-old horse fossil—by far the oldest genomic data ever obtained. But as astonishingly old as that genetic material was, some experts predicted that sequenceable DNA should survive more than a million years in fossils preserved in frozen environments.<br /><br />The new findings, published today in Nature, bear that prediction out. Tom van der Valk and Love Dalén of the Center for Paleogenetics in Stockholm and their colleagues obtained DNA from molar teeth belonging to three mammoths from different time periods. Mammoth species can be distinguished on the basis of dental characteristics. One tooth, discovered in deposits thought to be around 700,000 years old, looked like that of an early woolly mammoth, Mammuthus primigenius. The other two teeth—one dated to around one million years ago and the other to 1.2 million years ago or more—resembled molars of the steppe mammoth, Mammuthus trogontherii.<br /><br />The genetic material extracted from the teeth was highly degraded, having fragmented into lots of tiny pieces over the millennia. To reassemble the pieces and help filter out any DNA from microbes or other contaminants, the researchers used the genomes of modern-day elephants as guides, much as someone solving a jigsaw puzzle might refer to the image on the box. </p><p>In all they recovered billions of DNA base pairs from the youngest fossil (the woolly mammoth)—about 70 to 80 percent of the genome. They got hundreds of millions of base pairs constituting around 25 to 30 percent of the genome of the second oldest mammoth. The oldest fossil yielded the least DNA, but the team still sequenced around 60 million base pairs from it—enough to provide insights into mammoth evolution.<br /><br />The fossil record of mammoths indicates that they arose around five million years ago in Africa and spread across much of the world, evolving into number of species and enduring for millions of years before going extinct just a few thousand years ago. Comparing the new genomic data to genomes of younger mammoths, the researchers confirmed their expectation that the woolly mammoth evolved from the steppe mammoth, and they showed that it gradually acquired its adaptations to the extreme cold of ice age Siberia.<br /><br />The results also revealed surprises about another branch of the mammoth family tree. The oldest mammoth the team sampled turned out to belong to a previously unknown lineage that was ancestral to the mammoths that colonized North America 1.5 million years ago during the early Pleistocene epoch and gave rise to the Columbian mammoth that inhabited temperate regions of North and Central America. The Columbian mammoth may have been the product of interbreeding between woolly mammoths and members of the lineage to which the researchers’ oldest fossil specimen belonged, they suggest.<br /><br />Outside experts say the work represents a significant advance in ancient DNA research. “It’s an exciting study revealing DNA survival beyond what many in the field would have predicted being the upper limit just a decade ago,” remarks Eske Willerslev of the University of Copenhagen, whose team recovered the 700,000-year-old horse genome in 2013. He and his colleagues were among the researchers who calculated that DNA more than a million years old could survive in permafrost conditions. “Now this has been proven,” he says. <br /><br />“This is a very exciting study, not only because it pushes back the age of the oldest DNA yet recovered, but because the DNA that the team obtained from these very ancient mammoths provides important insights into early mammoth populations and into the origins of later mammoths both in Europe and the Americas,” says Janet Kelso of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. <br /><br />Mammoths are not the only creatures of interest from this time period. Dalén, van der Valk and their colleagues note that many modern-day mammal and bird species got their start in the Early and Middle Pleistocene. At a press teleconference on February 16, Dalén said that the team is starting projects looking into some of these species, including horses, musk ox and various rodents.<br /><br />Can scientists expect to recover DNA from similarly ancient human ancestors? The human fossil record spans up to seven million years. The oldest human DNA comes from remains dated to 430,000 years ago. “We know that environmental conditions matter a lot for the preservation of DNA. The extraordinary preservation of these mammoth specimens is likely thanks to the fact that they have been ‘on-ice’—frozen in Northern Siberia since the death of these mammoths,” says Kelso, who has studied a number of ancient human genomes. “The ancient humans that have been discovered so far are not found in such ideal conditions, and our view back into the human past is unfortunately therefore still limited.”<br /><br />But all hope is not lost. “Every year there are new innovations in methods,” Dalén said at the press teleconference. “Maybe a number of years in the future the methods will be there to recover DNA from human nonpermafrost specimens that are getting close to a million years old.” Alternatively, he added, “it is quite possible that in the future someone will find human remains frozen in permafrost of that age.  <br /></p><p><b><span style="font-family: trebuchet;"><i><u>The study was published in the journal <a href="https://www.nature.com/articles/d41586-021-00436-x#ref-CR1" rel="nofollow" target="_blank">Nature.</a></u></i></span></b><br /></p>

World's Oldest DNA Found in Siberian Mammoth Teeth

An illustration of the mammoth.   Scientists have recovered DNA from mammoth fossils found in Siberian permafrost that are more than a milli...

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