October 2022

Gravity Is Still Shaping Earth's Surface From Deep Within, New Study Finds

<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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEikZK4sFFoL8TUzdJvEi-HQFxFghSKQa4ele7mbX3sBFh2Pq5Y2bWrCtwSfZNewZAYvUZ34I0noK_o8xSPsmc_nnrbAZrx9SvfjvIfWig8wo8qiwEKTyiMQXkfwMxOHIsh78t79oDyW8tzq0IDhFTyDSBdARnJXzOFj8Go5GFhODqv1xCsgzGojLodI/s1255/Gravity%20Is%20Still%20Shaping%20Earth's%20Surface%20From%20Deep%20Within,%20New%20Study%20Finds.jpeg" style="margin-left: auto; margin-right: auto;"><img alt="A map of Earth's 'geoid'. The shape the planet would take under the influence of gravity if there were no winds and tides. (ESA/HPF/DLR)" border="0" data-original-height="686" data-original-width="1255" height="350" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEikZK4sFFoL8TUzdJvEi-HQFxFghSKQa4ele7mbX3sBFh2Pq5Y2bWrCtwSfZNewZAYvUZ34I0noK_o8xSPsmc_nnrbAZrx9SvfjvIfWig8wo8qiwEKTyiMQXkfwMxOHIsh78t79oDyW8tzq0IDhFTyDSBdARnJXzOFj8Go5GFhODqv1xCsgzGojLodI/w640-h350/Gravity%20Is%20Still%20Shaping%20Earth's%20Surface%20From%20Deep%20Within,%20New%20Study%20Finds.jpeg" title="Gravity Is Still Shaping Earth's Surface From Deep Within, New Study Finds" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">A map of Earth's 'geoid'. The shape the planet would take under the influence of gravity if there were no winds and tides. (ESA/HPF/DLR)<br /></td></tr></tbody></table><div class="separator" style="clear: both; text-align: center;"><br /></div><p><span style="font-family: georgia;">Like all planets, Earth is the product of gravity. Bit by bit, the growing mass of dust and rock drew in sufficient material to become a swollen sphere of mineral we now call home.</span><br /><br />Stony Brook University is leading a research project that focuses on the interplay between the evolution of the landscape, climate and fossil record of mammal evolution and diversification in the Western United States. A little explored aspect of this geosciences research is the connection between gravitational forces deep in the Earth and landscape evolution. Now in a newly published paper in Nature Communications, the researchers show by way of computer modeling that deep roots under mountain belts (analogous to the massive ice below the tip of an iceberg) trigger dramatic movements along faults that result in collapse of the mountain belt and exposure of rocks that were once some 15 miles below the surface.<br /><br />The origin of these enigmatic exposures, called ‘metamorphic core complexes,’ has been hotly debated within the scientific community. This study finding may alter the way scientists attempt to uncover the history of Earth as an evolving planet.<br /><br />Lead principal investigator William E. Holt, PhD, a Professor of Geophysics the Department of Geosciences in the School of Arts and Sciences at Stony Brook University, first author Alireza Bahadori, a former PhD student under Holt and now at Columbia University, and colleagues found that these core complexes are a fossil signature of past mountain belts in the Western United States that occupied regions around Phoenix and Las Vegas. These mountain areas left traces in the form of gravel deposits from ancient northward and eastward flowing rivers, found today south and west of Flagstaff, Arizona.<br /><br /></p><div style="margin: 0px auto; width: 100%;">
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</div><br />The work articulated in the paper highlights the development of what the research team terms as a general model for metamorphic core complex formation and a demonstration that they result from the collapse of a mountain belt supported by a thickened crustal root.<br /><br />The authors further explain: “We show that gravitational body forces generated by topography and crustal root cause an upward flow pattern of the ductile lower-middle crust, facilitated by a detachment surface evolving into a low-angle normal fault. This detachment surface acquires large amounts of finite strain, consistent with thick mylonite zones found in metamorphic core complexes.”<br /><br />The work builds on research also published in Nature Communications in 2022. Holt and colleagues published a first-of-a-kind model in three dimensions to illustrate the linkage between climate and tectonics to simulate the landscape and erosion/deposition history of the region before, during and after the formation of these metamorphic core complexes.<br /><br />This modeling was linked to a global climate model that predicted precipitation trends throughout the southwestern U.S. over time. The 3-D model accurately predicts deposition of sediments in basins that contain the mammal fossil and climate records.<br /><br />The group also published a paper in Science Advances in November 2021, led by team member Katie Loughney (Tectonic influence on Cenozoic mammal richness and sedimentation history of the Basin and Range, western North America).<br /><br />This research showed that a major peak in mammal diversification can be statistically tied to the peak in extensional collapse of the ancient mountain belts. Thus, the collaborative study is the first of its kind to quantify how deep Earth forces combine with climate to influence the landscape and impact mammal diversification and species dispersal found within the fossil record.<br /><br />The study required the vast computing resources provided by the High-Performance Computing Cluster SeaWulf at Stony Brook University. The climate modeling, produced by Ran Feng, University of Connecticut, was supported by the Cheyenne supercomputer maintained at NCAR-Wyoming Supercomputing Center. <p></p><p><br /></p><p><i><u>The above story is based on <a href="https://www.aau.edu/research-scholarship/featured-research-topics/study-shows-gravitational-forces-deep-within-earth" rel="nofollow" target="_blank">Materials</a> provided by<a href="https://news.stonybrook.edu/" rel="nofollow" target="_blank"> Stony Brook University</a></u></i><i style="-webkit-text-stroke-width: 0px; background-color: white; border: 0px none; box-sizing: inherit; color: #606060; font-family: "pt sans", Arial, sans-serif; font-size: 18px; font-stretch: inherit; font-style: italic; font-variant-caps: normal; font-variant-east-asian: inherit; font-variant-ligatures: normal; font-variant-numeric: inherit; font-weight: 400; letter-spacing: normal; line-height: inherit; margin: 0px; orphans: 2; padding: 0px; text-align: left; text-decoration-color: initial; text-decoration-style: initial; text-decoration-thickness: initial; text-indent: 0px; text-transform: none; vertical-align: baseline; white-space: normal; widows: 2; word-spacing: 0px;"><span><u> </u><br /></span></i></p>

Gravity Is Still Shaping Earth's Surface From Deep Within, New Study Finds

A map of Earth's 'geoid'. The shape the planet would take under the influence of gravity if there were no winds and tides. (ESA/...

Rhodochrosite: Manganese Carbonate Mineral

Geochemistry, Mineralogy, Minerals 9:01 PM

<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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhH-ba95f3fDXv6bLru09kZ1j9wrskTNFdzDr-MtG2h4MIY9fgJ17j8TT2xVwJa_cNUIJMPSUPbg3qCX0m9g52mla50mPfIec_6ffLRipYOt0KTra6Asoe0L3xTi0cffOjo1Ov0CRsTD1T5AsqqL4y410TYfwDqjohRhd13i1s7tv6UpeCV4mkqloXG/s1361/Rhodochrosite%20is%20a%20manganese%20carbonate%20mineral%20with%20chemical%20composition%20MnCO3.jpg" style="margin-left: auto; margin-right: auto;"><img alt="Rhodochrosite: Manganese Carbonate Mineral" border="0" data-original-height="722" data-original-width="1361" height="341" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhH-ba95f3fDXv6bLru09kZ1j9wrskTNFdzDr-MtG2h4MIY9fgJ17j8TT2xVwJa_cNUIJMPSUPbg3qCX0m9g52mla50mPfIec_6ffLRipYOt0KTra6Asoe0L3xTi0cffOjo1Ov0CRsTD1T5AsqqL4y410TYfwDqjohRhd13i1s7tv6UpeCV4mkqloXG/w640-h341/Rhodochrosite%20is%20a%20manganese%20carbonate%20mineral%20with%20chemical%20composition%20MnCO3.jpg" title="Stunning Rhodochrosite stalactite from Capillitas Mine, Andalgalá, Catamarca, Argentina Credit: Argentina Minerals" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><div data-contents="true"><div data-block="true" data-editor="29iaf" data-offset-key="4i9f6-0-0"><div class="public-DraftStyleDefault-block public-DraftStyleDefault-ltr" data-offset-key="4i9f6-0-0">Rhodochrosite: Manganese Carbonate Mineral.  Rhodochrosite stalactite from Capillitas Mine, Andalgalá, Catamarca, Argentina</div></div><div data-block="true" data-editor="29iaf" data-offset-key="4i2hh-0-0"><div class="public-DraftStyleDefault-block public-DraftStyleDefault-ltr" data-offset-key="4i2hh-0-0">Credit: Argentina Minerals</div></div></div></td></tr></tbody></table><p></p><p></p><p><span style="color: white;"><span style="font-size: xx-small;">
</span></span><span style="font-family: georgia;"><b><span style="color: white;"><span style="font-size: xx-small;">Rhodochrosite: Manganese Carbonate Mineral </span></span><br />Rhodochrosite </b>is a manganese carbonate mineral with  chemical composition MnCO<sub>3</sub>. In its (rare) pure form, it is typically a  rose-red color, but impure specimens can be shades of <b>pink </b>to pale  brown.</span></p><div dir="ltr"><span style="font-family: georgia;">It was first described in 1813 in reference to a sample  
from Cavnic, Maramureş, present-day Romania. According to Dimitrescu and
  Radulescu, 1966 and to Papp, 1997, this mineral was described for the 
 first time in <b>Sacaramb, Romania</b>, not in Cavnic, Romania. The name is  derived from the Greek word ῥοδόχρως meaning <b>rose-colored</b>.</span></div><div dir="ltr"><span style="font-family: georgia;"> </span></div><div dir="ltr"><div dir="ltr"><span style="font-family: georgia;">
It <b>streaks </b>white, and its <b>Mohs hardness</b> varies between 3.5
  and 4. Its specific gravity is between 3.5 and 3.7. It crystallizes in
  the trigonal system, and cleaves with <b>rhombohedral</b> carbonate cleavage in  three directions. </span></div><div dir="ltr"><span style="font-family: georgia;"><br /></span></div><div dir="ltr"><div dir="ltr"><span style="font-family: georgia;">Rhodochrosite occurs as a <b>hydrothermal vein</b> 
mineral along  with other manganese minerals in low temperature ore 
deposits as in the  silver mines of Romania where it was first found. 
Banded rhodochrosite  is mined in <b>Capillitas, Argentina</b>.</span></div><div dir="ltr"><span style="font-family: georgia;"> </span></div><div dir="ltr"><div style="margin: 0px auto; width: 100%;">
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</div></div><div dir="ltr"><div dir="ltr"><span style="font-family: georgia;">Rhodochrosite forms a complete solid solution series with
  iron carbonate (siderite). Calcium, (as well as magnesium and zinc, to
 a  limited extent) frequently substitutes for manganese in the 
structure,  leading to lighter shades of<b> red and pink</b>, depending on the degree of  substitution. It is for this reason that the most common color  encountered is pink.</span></div><div dir="ltr"><span style="font-family: georgia;"> </span></div><div dir="ltr"><div dir="ltr"><span style="font-family: georgia;">Its main use is as an ore of manganese which is a key  component of <b>low-cost stainless</b> steel formulations and certain aluminium  alloys. </span></div><div dir="ltr"><span style="font-family: georgia;"><br /></span></div><div dir="ltr"><span style="font-family: georgia;">The formation of rhodochrosite usually occurs in fractures and cavities of <b>metamorphic</b> and <b>sedimentary</b> rocks. It is often associated with silver deposits, and a few silver mines produce rhodochrosite as a byproduct. Some of the common modes of occurrence and their lapidary uses are described below.</span></div><div dir="ltr"><span style="font-family: georgia;"><br />In massive form, Rhodochrosite’s pink and white bands are extremely attractive and often used in semi-precious jewelry, <b>decorative</b> stones or carved into figurines, while stalactitic forms are cross-cut in slices to display their unique concentric bands. Fine transparent crystals are rare and costly, sometimes faceted into gems for collectors, however the softness and brittleness limit it as a gemstone for everyday usage. <br /><br />Rhodochrosite is a secondary source for <b>manganese</b> metal, used for aluminum alloys, brilliant transparent verities as a decorative stone, and jewelry.<br /><br /></span></div><div dir="ltr"><span style="font-family: georgia;">Rhodochrosite occurs in bedded, marine, sedimentary deposits along with various <b>Mn oxides. </b>These deposits are thought to mostly represent chemical sediments, although sometimes there does seem to be an association with volcanic rocks, suggesting that precipitation from hot springs could be important, rather akin to the proposed environment of Algoma type banded iron formations.<br /></span></div><div dir="ltr"><span style="font-family: georgia;"><br />Massive material from Argentina occurs in large pieces. Gem cutters have cabbed and carved this material into decorative as well as useful objects, such as <b>boxes</b>. Aggregate rhodochrosites can show white or grey jagged bands. Facetable, translucent pink material cuts stones up to about 20 carats.</span><br /><br /></div></div>  <br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-tCb70kcf0w4/WSl1Y2yNDjI/AAAAAAAAMc8/CkcvO4-Up8UjrUi2Cdpx-ke-b6hqeimGwCLcB/s1600/rhodochrosite%2Bresembling%2Ba%2Bpink%2Bsnowflake%2521.jpg" style="margin-left: auto; margin-right: auto;"><img alt="The trapiche-like rhodochrosite “flower”  from Argentina’s Capillitas mine." border="0" data-original-height="921" data-original-width="960" height="383" src="https://1.bp.blogspot.com/-tCb70kcf0w4/WSl1Y2yNDjI/AAAAAAAAMc8/CkcvO4-Up8UjrUi2Cdpx-ke-b6hqeimGwCLcB/w400-h383/rhodochrosite%2Bresembling%2Ba%2Bpink%2Bsnowflake%2521.jpg" title="The trapiche-like rhodochrosite “flower”  from Argentina’s Capillitas mine." width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-family: times;">The trapiche-like rhodochrosite “flower”  from Argentina’s Capillitas mine.<br />
Credit:  Russell E. Behnke</span></td></tr>
</tbody></table></div></div> </div><div dir="ltr"><b>The Capillitas mine</b> in Argentina’s Catamarca Province has also produced very rare trapiche-like rhodochrosites. Some sections of stalactitic rhodochrosites have revealed stunning, star-like “floral” patterns.<span style="font-family: georgia;"><span style="font-size: small;"><br /><br /></span></span></div><div dir="ltr"><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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj-foxY7BuzhZZrhIEDrLElj75Fw8-4MeiCG8vBJweD6OgqaoHuxRK3RThv3oCZOQlxtMNItoZg4MuNa0USq-xnQhGBKA2j29YwEf0BkEQCaD5cSvCmXQJ3atuc0wZ3u0ObvMYyNk9jYMflTJwkF1DXWkbJ5y3e6UZWY1u4UPksBPOSfT8InzwOWoRg/s1080/Lustrous%20Rhodochrosite%20Scalenohedrons%20from%20the%20N'chwaning%20Mine,%20Kalahari%20Mn%20Fields,%20Northern%20Cape%20Province,%20South%20Africa.jpg" style="margin-left: auto; margin-right: auto;"><img alt="Lustrous Rhodochrosite Scalenohedrons from the N'chwaning Mine, Kalahari Mn Fields, Northern Cape Province, South Africa.å Credit: Anatoly Bitny" border="0" data-original-height="957" data-original-width="1080" height="355" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj-foxY7BuzhZZrhIEDrLElj75Fw8-4MeiCG8vBJweD6OgqaoHuxRK3RThv3oCZOQlxtMNItoZg4MuNa0USq-xnQhGBKA2j29YwEf0BkEQCaD5cSvCmXQJ3atuc0wZ3u0ObvMYyNk9jYMflTJwkF1DXWkbJ5y3e6UZWY1u4UPksBPOSfT8InzwOWoRg/w400-h355/Lustrous%20Rhodochrosite%20Scalenohedrons%20from%20the%20N'chwaning%20Mine,%20Kalahari%20Mn%20Fields,%20Northern%20Cape%20Province,%20South%20Africa.jpg" title="Lustrous Rhodochrosite Scalenohedrons from the N'chwaning Mine, Kalahari Mn Fields, Northern Cape Province, South Africa.å Credit: Anatoly Bitny" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-family: times;">Lustrous Rhodochrosite Scalenohedrons from the N'chwaning Mine, Kalahari Mn Fields, Northern Cape Province, South Africa.</span><br /><b>Credit: Anatoly Bitny</b></td></tr></tbody></table><span style="font-size: small;"><br /><br /></span><span style="font-family: georgia;"><b>South African rhodochrosites</b> have a rich, rose red color but rarely occur in facetable crystals. The largest cut gems are in the 60-carat range.</span><br /> <br /><span style="font-family: times;">
</span><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://2.bp.blogspot.com/-6XWsimzacTQ/VzmqDI-yaNI/AAAAAAAAIaw/OhYqgW-m8QomASwEBnWExGX4Mit2bxbQwCLcB/s1600/Rhodochrosite%2Bavec%2BQuartz%252C%2BFluorite%2Bet%2Bsulfures.jpg" style="margin-left: auto; margin-right: auto;"><img alt="Facts About Rhodochrosite" border="0" height="266" src="https://2.bp.blogspot.com/-6XWsimzacTQ/VzmqDI-yaNI/AAAAAAAAIaw/OhYqgW-m8QomASwEBnWExGX4Mit2bxbQwCLcB/w400-h266/Rhodochrosite%2Bavec%2BQuartz%252C%2BFluorite%2Bet%2Bsulfures.jpg" title="Lustrous Rhodochrosite Scalenohedrons" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-family: times;"><span class="fbPhotosPhotoCaption" data-ft="{"tn":"K"}" id="fbPhotoSnowliftCaption" tabindex="0"><span class="hasCaption"><span dir="ltr">Rhodochrosite  avec Quartz, Fluorite et sulfures "Centennial pocket" <br />
of the Sweet Home  mine in Alma, Colorado, USA. <b><br />Collection & photo: Simone Citon</b></span></span></span></span></td></tr></tbody></table><span style="font-family: times;"><b> </b></span></div><div dir="ltr"><span style="font-family: georgia;"><b>Colorado produces pink gems</b>, perhaps the loveliest of all. Faceters have cut flawless gems up to about 15 carats. However, most stones range under five carats in size.</span><br /><br /></div><p><span style="font-family: georgia;"><b>See also:</b><br /><a href="https://www.geologyin.com/2020/02/chalcanthite-facts-about-chalcanthite.html" rel="nofollow" target="_blank">Chalcanthite: Facts About Chalcanthite<br /></a><a href="https://www.geologyin.com/2018/04/tourmaline-species-and-color-varieties.html" target="_blank">Tourmaline: Species and Color Varieties<br /></a><a href="https://www.geologyin.com/2017/02/why-fluorite-comes-in-different-colors.html" target="_blank">Why Fluorite Comes in Different Colors? </a></span><br /></p>

Rhodochrosite: Manganese Carbonate Mineral

Rhodochrosite: Manganese Carbonate Mineral. Rhodochrosite stalactite from Capillitas Mine, Andalgalá, Catamarca, Argentina Credit: Argentin...

Scientists Solve Mystery When California’s Iconic Yosemite Valley Formed

Geology, Granite, USA 10:43 PM

<p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgQ9abihCPihAaK_7LK11ZISucAgLVB3U9bH1l-KQQ_LGtpngr4OIIYTS6wW_3kHpkgMdrCbuwHiZBC0NiwyiVZJINaJc6ZEMKqP_amiVZTgAjEhrZCTx-4cEWdISAFeRC189Y0E9zmJubaH213lCooSCqyWe66ZxmYrt4nSh55PzQHWfGtwTFQPiHz/s1600/Scientists%20Solve%20Mystery%20When%20California%E2%80%99s%20Iconic%20Yosemite%20Valley%20Formedd.jpeg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="1067" data-original-width="1600" height="426" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgQ9abihCPihAaK_7LK11ZISucAgLVB3U9bH1l-KQQ_LGtpngr4OIIYTS6wW_3kHpkgMdrCbuwHiZBC0NiwyiVZJINaJc6ZEMKqP_amiVZTgAjEhrZCTx-4cEWdISAFeRC189Y0E9zmJubaH213lCooSCqyWe66ZxmYrt4nSh55PzQHWfGtwTFQPiHz/w640-h426/Scientists%20Solve%20Mystery%20When%20California%E2%80%99s%20Iconic%20Yosemite%20Valley%20Formedd.jpeg" title="Scientists Solve Mystery When California’s Iconic Yosemite Valley Formed" width="640" /></a></div> <br /><p></p><p style="text-align: left;">First-time visitors to Yosemite Valley gape in awe at the sheer granite wall of El Capitan and the neatly sliced face of Half Dome, aware, perhaps vaguely, that rain and glaciers must have taken a long time to cut and sculpt that landscape. But how long?<br /><br />Did it all start 50 million years ago, when the granite through which the valley cuts was first exposed to the elements? Was it 30 million years ago, when data suggest canyons in the southern Sierra Nevada began to form? Did the valley only begin to form after the Sierra tilted toward the west some 5 million years ago, or was it mostly due to glaciers that formed in a cooling climate 2 to 3 million years ago?<br /><br />Geologists from the University of California, Berkeley, employed a novel technique of rock analysis to get a more precise answer, and concluded that much of Yosemite Valley's impressive depth was carved since 10 million years ago, and most likely even more recently -- over the past 5 million years. This shaves about 40 million years off the oldest estimates.<br /><br />Rivers performed the initial carving in a preexisting shallow valley, they determined, and then both rivers and ice contributed recently.<br /><br />While the scientists are unable to be more precise, the new estimate is the first to be based on an experimental study of the granite rocks in and near Yosemite, rather than on inferences based on what was going on elsewhere in the Sierra Nevada.<br /><br />"Yosemite Valley is one of the most famous topographic features on the planet," said glaciologist Kurt Cuffey, UC Berkeley professor of geography and of earth and planetary science. "And of course, if you go to Yosemite Park and read the signage, they will give you numbers for when it became a deep canyon. But up until this project, every single claim about how old this valley is, when it formed a deep canyon, was just based on assumptions and speculation."<br /><br />Yosemite National Park geologist Greg Stock admits that the story told about the origin of the park's iconic granite topography has been a little vague, because geologists still do not agree about what has happened since the Sierra's signature granite formed underground between about 80 and 100 million years ago, up to 10 kilometers (6 miles) under a mountain range that looked a lot different than it does today.<br /><br />"We know that the Sierra was a high mountain range 100 million years ago, when the granite was forming at depth. It was a chain of volcanoes that might have looked a bit like the Andes Mountains in South America," Stock said. "The question really is whether the elevation has just been coming down through erosion since that time or whether it came down some and then was uplifted again more recently. At this point, based on studies I've done for most of my career and supported by this study, I see a lot of evidence for recent uplift happening sometime in the last 5 million years."<br /><br />That uplift, which happened at the same time that earthquake faulting in the eastern Sierra Nevada created an escarpment several kilometers high, steepened the western slopes and rivers, causing them to incise valleys more quickly.<br /><br />Cuffey, UC Berkeley geochemist David Shuster and their colleagues, including Stock, published the findings this week in the journal Geological Society of America Bulletin.<br /></p><h4 style="text-align: left;">Rock cooldown</h4><p style="text-align: left;">Shuster, a professor of earth and planetary science, developed a technique 15 years ago that he thought at the time might shed light on the origins of the valley, something that has fascinated both him and Cuffey since they first saw Yosemite as kids. Shuster, a California native, has visited it since early childhood. Cuffey, from central Pennsylvania, made his first trip to the park at the age of 15.<br /><br />Much of what they remember learning is that the valley was carved by glaciers, giving short shrift to what happened before Ice Age glaciers arrived in the Pleistocene some 2.5 million years ago.<br /><br />"What I learned from the signage in the valley when I was a kid wasn't quite right, given what the scientific literature said at the time. Nevertheless, the topography has been interpreted to be significantly modified by ice," Shuster said. "How to quantify that with geochronological tools, rather than just make up a story about it based on geomorphology, is one thing we were trying to do here."<br /><br />Shuster's technique, called helium-4/helium-3 thermochronometry, reconstructs the temperature history of a sample of rock based on the spatial distribution of natural helium-4 in minerals, which is measured by comparison to an artificially-produced uniform distribution of helium-3. Because temperature increases with depth underground, the temperature history can tell when a rock was uncovered as the landscape eroded.<br /><br />"The temperature of the rock is a function of the surface lowering down into it," Shuster said. "It's very analogous to removing a down comforter -- the rock beneath it progressively gets colder. This progression through time with the rock cooling is what we get from the geochemistry and thermochronometry."<br /><br />The expectation is that granite bedrock exposed on the broad uplands of the Sierra should show a long history of cool surface temperatures, since they've been exposed for tens of millions of years longer than bedrock more recently exposed on the floor of Tenaya Canyon, which feeds into Yosemite Valley from the northeast.<br /><br />The experiments, conducted at the Berkeley Geochronology Center, indicated that, while rock from the uplands has been close to the surface for about 50 million years, bedrock at the bottom of Tenaya Canyon has been exposed much more recently. The temperature history of the rock obtained from the bottom of Tenaya Canyon -- from an exposed area of bedrock at the base of Half Dome -- indicates that it was more than a kilometer underground 10 million years ago, and most likely only 5 million years ago. This means that a kilometer of rock was eroded away since that time.<br /><br />"This upland surface that people are familiar with from parts of the Tioga Road and Tuolumne Meadows -- that's a very old landscape," said Cuffey, who is the Martin Distinguished Chair in Ocean, Earth and Climate Science. "The question is: What about the deep canyon? Is that also very old, or is it relatively young? And what we found in our study, our big contribution, is that it's fairly young. The best guess for the timing is in the last 3 to 4 million years, but maybe as far back as 10 million years for the start of the rapid incision."<br /></p><h4 style="text-align: left;">Bedrock studies</h4><p style="text-align: left;">The geologists collected samples of granite bedrock from nearby highlands and the bottom of Tenaya Canyon, but not from the bedrock bottom of Yosemite Valley itself, which lies buried under about 500 meters (1/3 mile) of sediment that today forms the valley floor. But since the two formed at the same time, one can infer the timing of the formation of Yosemite Valley from the time of the scouring of Tenaya Canyon.<br /><br />"The brief history of Yosemite Valley would be that there was some kind of valley in place for tens of millions of years -- a river-carved canyon associated with the ancient Sierra Nevada. And then, in the last 5 million years or so, renewed uplift of the range through westward tilting caused rivers to steepen and deepen the canyons that they were in," Stock said. "So, that probably carved out more of Yosemite Valley and may have started forming Tenaya Canyon. And then in the last 2 to 3 million years, as the climate cooled and glaciers came down through Tenaya Canyon and into Yosemite Valley, they further sculpted the rock, deepening those valleys. And in the case of Yosemite Valley, widening it out considerably. So, there's some component of an old Yosemite Valley. But I think this recent work shows that much more of that topography is younger, rather than older."<br /><br />Stock, who has held the position of park geologist for 17 years and is the park's first geologist, said the new study will revise how the park tells the geological history of Yosemite Valley.<br /><br />"The timing of this new study is perfect in the sense that, over the next several years, we're hoping to completely redo the Geology Hut displays at Glacier Point. I'm very excited to include these new results in those displays," he said. "It's a perfect place to tell that story, because there's a view straight up Tenaya Canyon."<br /><br /></p><p style="-webkit-text-stroke-width: 0px; box-sizing: border-box; font-size: 14px; font-style: normal; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; line-height: 21px; margin-bottom: 21px; margin-top: 0px; text-align: left; 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 style="font-family: trebuchet;"><span style="box-sizing: border-box;"><em style="box-sizing: border-box;">The above post is reprinted from <a href="https://news.berkeley.edu/2022/10/20/how-old-is-yosemite-valley/" rel="nofollow" style="background-color: transparent; box-sizing: border-box;" target="_blank">materials</a> provided by <a href="https://www.berkeley.edu/" rel="nofollow" style="background-color: transparent; box-sizing: border-box;" target="_blank">University of California – Berkeley</a>. Original written by Robert Sanders.</em></span></span></p>

Scientists Solve Mystery When California’s Iconic Yosemite Valley Formed

First-time visitors to Yosemite Valley gape in awe at the sheer granite wall of El Capitan and the neatly sliced face of Half Dome, aware,...

Magma Activity Found Beneath Alaska’s Mount Edgecumbe

Magma, USA, volcano 9:39 PM

<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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjcDAHWBg8Ff9-g62xfTDfoWpe8o2400nvRYJFEYj17ontHv6YXLRy9OoTtx6FksshGAjXpBQzQYh_PmJq0EPYNwdYKQnkNQhNHRztjpPtJV0JzGcdhoHOBTQDkbP-aZRzPR6sVSWoKmJMJPkh1nhgbGYfNONo3zI0-JgQ4lbFCktN962S0cGKQ0O73/s1200/Magma%20Activity%20Found%20Beneath%20Alaska%E2%80%99s%20Mount%20Edgecumbe%20(1).jpeg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="900" data-original-width="1200" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjcDAHWBg8Ff9-g62xfTDfoWpe8o2400nvRYJFEYj17ontHv6YXLRy9OoTtx6FksshGAjXpBQzQYh_PmJq0EPYNwdYKQnkNQhNHRztjpPtJV0JzGcdhoHOBTQDkbP-aZRzPR6sVSWoKmJMJPkh1nhgbGYfNONo3zI0-JgQ4lbFCktN962S0cGKQ0O73/w640-h480/Magma%20Activity%20Found%20Beneath%20Alaska%E2%80%99s%20Mount%20Edgecumbe%20(1).jpeg" title="Mt. Edgecumbe photographed from the air (Photo by Max Kaufman/USGS)" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Mt. Edgecumbe photographed from the air (Photo by Max Kaufman/USGS)</td></tr></tbody></table> <br /></p><p>Magma beneath long-dormant Mount Edgecumbe volcano in Southeast Alaska has been moving upward through Earth's crust, according to research the Alaska Volcano Observatory rapidly produced using a new method.<br /><br />The new approach at the observatory could lead to earlier detection of volcanic unrest in Alaska.<br /><br />At Mount Edgecumbe, computer modeling based on satellite imagery shows magma is rising to about 6 miles from a depth of about 12 miles and has caused earthquakes and significant surface deformation.<br /><br />"That's the fastest rate of volcanic deformation that we currently have in Alaska," said the research paper's lead author, Ronni Grapenthin, a University of Alaska Fairbanks associate professor of geodesy.<br /><br />"And while it is not uncommon for volcanoes to deform, the activity at Edgecumbe is unusual because reactivation of dormant volcanic systems is rarely observed," he said.<br /><br />An eruption is not imminent, Grapenthin said.<br /><br />The findings by researchers at the UAF Geophysical Institute and the U.S. Geological Survey were published Oct. 10 in the journal Geophysical Research Letters.<br /><br />The Alaska Volcano Observatory collaborated with the Alaska Satellite Facility, another Geophysical Institute unit, to process data in the cloud -- a first for the volcano team.<br /><br />Cloud computing uses remote servers to store data and provide computing services so a researcher does not have to download and sort data to process it, something that can take weeks or months.<br /><br />The research team began its work as soon as a swarm of earthquakes was noticed at Mount Edgecumbe on April 11, 2022. Researchers analyzed the previous 7 1/2 years of ground deformation detected in satellite radar data.<br /><br />Four days later, on April 15, the team had a preliminary result: An intrusion of new magma was causing the earthquakes. A small number of earthquakes began under Edgecumbe in 2020, but the cause was ambiguous until the deformation results were produced.<br /><br />Additional data processing confirmed the preliminary finding. The Alaska Volcano Observatory informed the public on April 22, less than two weeks after the latest batch of Edgecumbe earthquakes was reported.<br /><div style="margin: 0px auto; width: 100%;">
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</div><br />"We've done these kinds of analyses before, but new streamlined cloud-based workflows cut weeks or months of analysis down to just days," said David Fee, the Alaska Volcano Observatory's coordinating scientist at the Geophysical Institute.<br /><br />Mount Edgecumbe, at 3,200 feet, is on Kruzof Island on the west side of Sitka Sound. It is part of the Mount Edgecumbe Volcanic Field, which includes the domes and crater of adjacent Crater Ridge.<br /><br />Most striking for the researchers was an area of ground uplift on southern Kruzof Island 10.5 miles in diameter and centered 1.5 miles east of the volcano. The upward deformation began abruptly in August 2018 and continued at a rate of 3.4 inches annually, for a total of 10.6 inches through early 2022.<br /><br />Subsequent computer modeling indicated the cause was the intrusion of new magma.<br /><br />The new deformation-based analysis will allow for earlier detection of volcanic unrest, because ground deformation is one of its earliest indicators. Deformation can occur without accompanying seismic activity, making ground uplift a key symptom to watch.<br /><br />The volcano observatory is applying the new approach to other volcanoes in Alaska, including Trident Volcano, about 30 miles north of Katmai Bay. The volcano is showing signs of elevated unrest.<br /><br />Mount Edgecumbe isn't showing signs of an imminent eruption, Grapenthin said.<br /><br />"This magma intrusion has been going on for three-plus years now," he said. "Prior to an eruption we expect more signs of unrest: more seismicity, more deformation, and -- importantly -- changes in the patterns of seismicity and deformation."<br /><br />The researchers say the magma is likely reaching an upper chamber through a near-vertical conduit. But they also believe the magma is precluded from moving further upward by thick magma already in the upper chamber.<br /><br />The new magma is forcing the entire surface up instead.<br /><br />Mount Edgecumbe is 15 miles west of Sitka, which has a population of about 8,500 residents.<br /><br />The volcano last erupted 800 to 900 years ago, as cited in Lingít oral history handed down by Herman Kitka. A group of Tlingits in four canoes had camped on the coast about 15 or 20 miles south of some large smoke plumes, according to the account. A scouting party in a canoe was sent to investigate the smoke and reported "a mountain blinking, spouting fire and smoke."<br /><br />Others involved in the research include Franz Meyer, chief scientist of the Alaska Satellite Facility; UAF graduate students Yitian Cheng, Mario Angarita and Darren Tan; and Aaron Wech of the U.S. Geological Survey.</p><p> </p><p><i><u><span style="font-family: trebuchet;"> The above story is based on <a href="https://www.gi.alaska.edu/news/research-reveals-magma-activity-beneath-mount-edgecumbe" rel="noopener noreferrer 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://www.uaf.edu/uaf/" rel="noopener noreferrer 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 Alaska Fairbanks</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 Rod Boyce.</span></span></u></i></p>

Magma Activity Found Beneath Alaska’s Mount Edgecumbe

Mt. Edgecumbe photographed from the air (Photo by Max Kaufman/USGS) Magma beneath long-dormant Mount Edgecumbe volcano in Southeast Alaska...

Boleite Crystal Information

Minerals 10:00 PM

<p></p><p>Boleite is a complex halide mineral. Boleite is a rare secondary mineral from copper deposits, typical of arid climates in a chlorinated environment (closed basins, evaporite lagoons, and marine littoral). The external property of a boleite crystal structure indicates its cubic structure. <br /></p><p><br />Boleite is classified under the isometric crystal class. Boleite has a perfect cleavage in the [001] direction, and has a very dark glossy blue color with a light greenish-blue color streak.<br /></p><div style="margin: 0px auto; width: 100%;">
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</div><br /><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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjGnR_ZLaOnDzSJM4eNiOLxSTY1uvrLC6Yo4Ha7t4OVb--obuVMYGEIQX_aWh55gZqdpuTXeVHS37Np9Nl_IVMvlIsD9WdVs56MP8O6XSnlQG4iZdOkhL5KzDz0UydRJGunlk76ErqAaxrF6J8qg5UVP2KOysxXMFpNYcz1F2p57RP10V4LtYbERFbN/s1046/Boleite%20ff%20(1).jpg" style="margin-left: auto; margin-right: auto;"><img alt="Boleite Crystal Information" border="0" data-original-height="782" data-original-width="1046" height="478" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjGnR_ZLaOnDzSJM4eNiOLxSTY1uvrLC6Yo4Ha7t4OVb--obuVMYGEIQX_aWh55gZqdpuTXeVHS37Np9Nl_IVMvlIsD9WdVs56MP8O6XSnlQG4iZdOkhL5KzDz0UydRJGunlk76ErqAaxrF6J8qg5UVP2KOysxXMFpNYcz1F2p57RP10V4LtYbERFbN/w640-h478/Boleite%20ff%20(1).jpg" title="Boleite" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Complete cluster of cumengeite crystals epitaxial on a boleite cube from Santa Rosalia, Boleo District, Baja California Sur, Mexico<br />Photo: Bucket of Holes Minerals/E-rocks</td></tr></tbody></table><br /><p></p><p>Twinning is best shown in this mineral by notches along the interpenetrated angles, which results in a crystal habit of pseudocubic penetration twinning along three different angles perpendicular to one another. </p><p><b>Formula:</b> KPb₂₆Ag₉Cu₂₄(OH)₄₈Cl₆₂.<br /><b>Colour:</b> Deep prussian blue to indigo; bluish green in transmitted light<br /><b>Lustre: </b>Vitreous, Pearly<br /><b>Hardness:</b> 3 - 3½ <br /><b>Crystal System:</b> Isometric<br /><b>Name: </b>For the occurrence at Boleo, Mexico.<br /><b>Occurrence:</b> A secondary mineral formed through reaction of 
chloride with primary sulfides in the oxidized zone of Pb–Cu deposits; 
in smelter slag immersed in and leached by sea water.<br /></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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg2qQL4Aauu3ApfeHRNDc04-NWLC5AzTrjsBCPEjEJR037Cnk6uPPYTwDxPWMCG78aDwNfbLnGfmEpTIz0BZdzICpx9-KMGQe3I0b-rh_2zJB7eboJ_WimVsYbR5eysF3a0DrqhNwyzX31chjgEAdGbE-84-9CpYjP6PVm0vR4XIVOKWql60rvjh9E4/s800/Boleite%20(1).jpeg" style="margin-left: auto; margin-right: auto;"><img alt="Boleite Crystal Information" border="0" data-original-height="600" data-original-width="800" height="300" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg2qQL4Aauu3ApfeHRNDc04-NWLC5AzTrjsBCPEjEJR037Cnk6uPPYTwDxPWMCG78aDwNfbLnGfmEpTIz0BZdzICpx9-KMGQe3I0b-rh_2zJB7eboJ_WimVsYbR5eysF3a0DrqhNwyzX31chjgEAdGbE-84-9CpYjP6PVm0vR4XIVOKWql60rvjh9E4/w400-h300/Boleite%20(1).jpeg" title="Boleite Crystal Information" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Boleite Crystal Information, <br />From: Curuglu Mine, Arroyo del Boleo, Mulegé Municipality, Baja California Sur, Mexico<br />Photo: Jean-Marc Johannet</td></tr></tbody></table><p>There are numerous minerals related to boleite, such as pseudoboleite, cumengite, and diaboleite, and these all have the same complex crystal structure.</p><p>Boleite was first collected as a very minor ore of silver, copper and lead at Boleo, Mexico. Minerals associated with boleite include pseudoboleite, cumengeite, atacamite, anglesite, cerussite, phosgenite and gypsum at the type locality in Boleo, Mexico. In the Mammoth-St. Anthony mine of Arizona associated minerals include pseudoboleite, anglesite, cerussite, atacamite, paratacamite, leadhillite, paralaurionite, caledonite, phosgenite, matlockite and bideauxite.<br /><br /></p><p></p>

Boleite Crystal Information

Boleite is a complex halide mineral. Boleite is a rare secondary mineral from copper deposits, typical of arid climates in a chlorinated env...

Dinosaur ‘Mummies’ Might Not Be As Unusual As We Think

dinosaur, Fossils 9:22 PM

<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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhlaQDKp-UnyqNh9Qee6v5NZq0jEnJF_XFzPau9OgV2OVyVaqwVx-9ia3W_6mGwffnTqLE_fvdqxH5shg4fwiJw-LilF_DCTGJxH3dq_RS_rlqvkm5k7ao_-zqX7n0ChnMJN_4-UtAO5y7Sww8Hxn7NzbzMu_gPX3RAJnRdFJJIKAhrAs3l0IPbpqp7/s1274/Dinosaur%20%E2%80%98Mummies%E2%80%99%20Might%20Not%20Be%20As%20Unusual%20As%20We%20Think.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="745" data-original-width="1274" height="374" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhlaQDKp-UnyqNh9Qee6v5NZq0jEnJF_XFzPau9OgV2OVyVaqwVx-9ia3W_6mGwffnTqLE_fvdqxH5shg4fwiJw-LilF_DCTGJxH3dq_RS_rlqvkm5k7ao_-zqX7n0ChnMJN_4-UtAO5y7Sww8Hxn7NzbzMu_gPX3RAJnRdFJJIKAhrAs3l0IPbpqp7/w640-h374/Dinosaur%20%E2%80%98Mummies%E2%80%99%20Might%20Not%20Be%20As%20Unusual%20As%20We%20Think.jpg" title="Dinosaur ‘Mummies’ Might Not Be As Unusual As We Think" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><i>Edmontosaurus</i>. Credit:  Natee Puttapipat, CC-BY</td></tr></tbody></table> <br /></p><p>The term “mummy” is often used to describe dinosaur fossils with fossilized skin. It is commonly suggested that such fossils only form under exceptional circumstances and that a carcass must be shielded from scavenging and decomposition by rapid burial and/or desiccation in order for skin to become fossilized.<br /><br />A process of desiccation and deflation explains why dinosaur "mummies" aren't as exceptional as we might expect, according to a study published in the open-access journal PLOS ONE by Stephanie Drumheller of the University of Tennessee-Knoxville and colleagues.<br /><br />The term "mummy" is often used to describe dinosaur fossils with fossilized skin, which are relatively rare. It is commonly suggested that such fossils only form under exceptional circumstances and that a carcass must be shielded from scavenging and decomposition by rapid burial and/or desiccation in order for skin to become fossilized. In this study, Drumheller and colleagues combine fossil evidence with observations on modern animal carcasses to propose a new explanation for how such "mummies" might form.<br /><div style="width:100%;margin: 0px auto">
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</div><br />The researchers examined a fossil of a dinosaur called <i>Edmontosaurus </i>from North Dakota which preserves large patches of desiccated and seemingly deflated skin on the limbs and tail. They identified bite marks from carnivores upon the dinosaur's skin. These are the first examples of unhealed carnivore damage on fossil dinosaur skin, and furthermore, this is evidence that the dinosaur carcass was not protected from scavengers, yet it became a mummy nonetheless.<br /><br />Modern animal carcasses are known to be often emptied out as scavengers and decomposers target internal tissues, leaving behind skin and bone. The authors propose that damage to this dinosaur's skin from this incomplete scavenging would have exposed its insides and allowed a similar process to occur, after which the skin and bones became slowly desiccated and buried.<br /><br />This process, which the authors call "desiccation and deflation," is common with modern carcasses and explains how dinosaur mummies might form under relatively ordinary circumstances. The authors stress that there are likely numerous pathways by which a dinosaur mummy might develop. Understanding these mechanisms will guide how paleontologists collect and interpret such rare and informative fossils.<br /><br />Clint Boyd, Senior Paleontologist at the North Dakota Geological Survey, adds: "Not only has Dakota taught us that durable soft tissues like skin can be preserved on partially scavenged carcasses, but these soft tissues can also provide a unique source of information about the other animals that interacted with a carcass after death."</p><p> </p><p><u><i> The above story is based on <span style="-webkit-text-stroke-width: 0px; background-color: white; display: inline !important; float: none; font-family: "Helvetica Neue", Helvetica, Arial, sans-serif; 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;">Materials provided by<span> </span></span><a href="https://plos.org/" rel="noopener noreferrer nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; font-family: "Helvetica Neue", Helvetica, Arial, sans-serif; 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;">PLOS</strong></a></i></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="color: black;"><i>.</i></span></u><span><u><span style="color: black;"><i> </i></span></u><br /></span></span></p>

Dinosaur ‘Mummies’ Might Not Be As Unusual As We Think

Edmontosaurus . Credit: Natee Puttapipat, CC-BY The term “mummy” is often used to describe dinosaur fossils with fossilized skin. It is c...

35-Million-Year-Old Amber Found To Contain An Unknown Group Of Insects

Amber Fossils, Earth History 9:09 PM

<p style="text-align: left;"></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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjbNkXf6ExKAU1AL8XDR4OTUx_Ol0DwXKaEXgDrKU-1zHZ9TFe7smFR_Lowpc3LrfrONJaZM9DJw3CR---MK_yZnFZ9i8FWYhkGDZW2O6HheXS6MeqE4Jb6ksWP_BgcMwQkeg1-9SFNAcEy73shd8x-rR4SqdMPaqIQbGWlV4MYj8J1WZ9BUTpohk4F/s1232/35-Million-Year-Old%20Amber%20Found%20To%20Contain%20An%20Unknown%20Group%20Of%20Insects.jpg" style="margin-left: auto; margin-right: auto;"><img alt="35-Million-Year-Old Amber Found To Contain An Unknown Group Of Insects" border="0" data-original-height="761" data-original-width="1232" height="396" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjbNkXf6ExKAU1AL8XDR4OTUx_Ol0DwXKaEXgDrKU-1zHZ9TFe7smFR_Lowpc3LrfrONJaZM9DJw3CR---MK_yZnFZ9i8FWYhkGDZW2O6HheXS6MeqE4Jb6ksWP_BgcMwQkeg1-9SFNAcEy73shd8x-rR4SqdMPaqIQbGWlV4MYj8J1WZ9BUTpohk4F/w640-h396/35-Million-Year-Old%20Amber%20Found%20To%20Contain%20An%20Unknown%20Group%20Of%20Insects.jpg" title="35-Million-Year-Old Amber Found To Contain An Unknown Group Of Insects" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">35-Million-Year-Old Amber Found To Contain An Unknown Group Of Insects. The male Calliarcys antiquus preserved in Eocene Baltic amber. Image credit: R Godunko et al,. Scientific Reports,<br /></td></tr></tbody></table><p> </p><p>A drop of ancient amber has given rise to a new-to-science group of insects with the aid of teeny tiny technology. Using microtomography (Micro-CT), researchers were able to confirm the existence of the genus <i>Calliarcys </i>contained within Eocene Baltic amber, representing a rare opportunity to learn more about ancient mayflies, which are hardly ever preserved in the sedimentary rock fossil record.<br /><br />The specimen itself was located by Arnold Staniczek of Stuttgart's State Museum of Natural History, set in a piece of Baltic amber estimated to be between 35 and 47 million years old. And, thanks to the specialist contribution of Professor Javier Alba-Tercedor of the UGR's Department of Zoology, using microtomography to obtain clear images of the insect, it could be studied and described in detail.<br /><br />Plants such as conifers (and certain legumes) protect themselves by secreting resin—a thick, sticky liquid—as a reaction to damage to the cortex of the specimen. As insects often become trapped in this resin, even those dating back millions of years may still be found to this day, preserved in the hardened, fossilized resin that we know as amber. There are amber deposits located in different parts of the world, including northern Spain, but those located in the Baltic region are the most abundant.<br /><br />"The conservation of the specimens trapped inside the amber is often excellent, and the transparency of the material that surrounds them enables them to be studied, under a microscope, in great detail," explains Professor Alba-Tercedor.<br /></p><div style="margin: 0px auto; width: 100%;">
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</div><br />"But, in other cases, the level of transparency is not good because the areas of opacity that form prevent certain details from being examined," comments Alba-Tercedor. When this limited transparency is problematic, X-ray microtomography (a technique similar to that used in hospitals to study patients' organs) is invaluable in studying fossil specimens that are preserved in amber.<br /><br />When Arnold Staniczek—a specialist in Ephemeroptera, with extensive experience in the study of insects preserved in amber—observed this particular piece from the Baltic, it was completely transparent. However, the insect itself presented certain "hyaline" (translucent) areas surrounding certain parts of the body that are essential for characterizing the specimen and distinguishing one species from another, such as the end of the abdomen where the male reproductive apparatus (genitalia) are located.<br /><br />As this translucence impeded the identification process, Staniczek turned to Alba-Tercedor, in his capacity as a specialist in Ephemeroptera and due to his recognized experience in the use of computerized microtomography (micro-CT) applied to the study of insects.<br /><br />From his base at the microtomography unit of the UGR's Department of Zoology, Professor Alba-Tercedor reconstructed the entire insect, including those areas otherwise impossible to observe due to the opacity of the amber. This particular specimen belongs to the genus <i>Calliarcys</i>, the first (formally described) species of which is found in the Iberian Peninsula.<br /><br />Thanks to the expert knowledge of Roman Godunko of the Institute of Entomology of the Czech Academy of Sciences, the study of the previously undescribed species of mayfly was then accomplished by comparing it with extant species of the genus. In addition, given the importance of molecular studies in characterizing species and determining their evolutionary position, the input of Polish experts from the University of Łódź was also sought.<br /><br />Hence, researchers Michal Grabowski and Tomasz Rewicz completed the study with a DNA analysis of extant species of the genus.<br /><br />"In short, it all started with the discovery of a beautiful insect preserved in amber, which attracted the attention of the expert eyes of a scientist. And which ultimately required the enthusiastic collaboration and detective work of five scientists based in research centers located in four countries, who, after applying the latest techniques, were finally able to name and describe an insect that has remained locked inside a drop of amber for millions of years," says Professor Alba-Tercedor.<br /><p></p><h4 style="text-align: left;">What is micro-CT?</h4><p style="text-align: left;">Micro-CT is a technique for producing a 3D image using X-rays. It uses the same method as computed tomography (CT) in medicine, but on a smaller scale and with a much higher resolution. While CT provides a resolution measured in millimeters, in micro-CT, resolutions of around 0.5 micrometers are achieved.<br /><br />Indeed, the new nano-CTs are increasing the resolution even further and expanding the possibilities the technology can offer. Micro-CT is based on 3D microscopy, which enables the internal structure of extremely small-scale objects to be captured non-invasively.<br /><br />No physical cross-sections or complex pre-treatments are required: with just a single scan, multiple radiographic images can be generated to obtain high-resolution 3D rendered images of the entire internal structure of the sample. And all of this while the sample is left intact for subsequent treatments.<br /><br />In simple terms, the procedure consists of an X-ray source illuminating the object and a flat X-ray detector capturing enlarged projection-images. Using computer software, the X-rays derived from the sample are then transformed into cross-sections that are converted into three-dimensional images using volumetric reconstruction programs. </p><p style="text-align: left;"><br /></p><p style="text-align: left;"><u><i>The above story is based on <a href="https://www.nature.com/articles/s41598-022-18234-4" rel="nofollow" target="_blank">materials </a>provided by <a href="http://www.ugr.es/ugr/index.php" rel="nofollow" target="_blank">University of Granada</a>.</i></u><br /></p>

35-Million-Year-Old Amber Found To Contain An Unknown Group Of Insects

35-Million-Year-Old Amber Found To Contain An Unknown Group Of Insects. The male Calliarcys antiquus preserved in Eocene Baltic amber. Image...

Emergence of Land Plants Altered Composition of Earth’s Continental Crust

Earth History, Geology, Tectonic 9:20 PM

<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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhynEwEmRHAeODhRx70ZJlrxTgHC403NeKUSvGdmBjTPf3ADl3nzSCbJ60XRDFSk2FadMYJ2noX9Gyo46VSMT8MbWE9u_KlGUhW1lEe4HNh-aQSQyednLuxeKs7MxCUO0uHUHC_B2QOKJS_5Y5r774fvZh8z6wYW7vb63qVLfdGt0JmNbFw78hRK3WL/s1280/Emergence%20of%20Land%20Plants%20Altered%20Composition%20of%20Earth%E2%80%99s%20Continental%20Crust%20(1).jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="806" data-original-width="1280" height="404" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhynEwEmRHAeODhRx70ZJlrxTgHC403NeKUSvGdmBjTPf3ADl3nzSCbJ60XRDFSk2FadMYJ2noX9Gyo46VSMT8MbWE9u_KlGUhW1lEe4HNh-aQSQyednLuxeKs7MxCUO0uHUHC_B2QOKJS_5Y5r774fvZh8z6wYW7vb63qVLfdGt0JmNbFw78hRK3WL/w640-h404/Emergence%20of%20Land%20Plants%20Altered%20Composition%20of%20Earth%E2%80%99s%20Continental%20Crust%20(1).jpg" title="mergence of Land Plants Altered Composition of Earth’s Contine" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-family: times;"><i>Schematic model of fluvial systems both before and after the development of land plants: before the Devonian period, minimal land plants, rapid channel migration and river systems dominated by braided rivers led to rapid sediment transfer, minimal development of mud-sized particles and minor deposition of mudrocks along continental margins; in contrast, after the Devonian, the expansion of vascular land plants led to the development of meandering rivers and the dramatic slowing of sediment transfer to marine environments</i></span></td></tr></tbody></table> <br /></p><p> Scientists at the University of Southampton have discovered that the 
evolution of land plants caused a sudden shift in the composition of 
Earth's continents.</p><p>The evolution of land plants took place about 430 million years ago (Silurian period), when North America and Europe were conjoined in a landmass called Pangaea, and transformed Earth’s biosphere. </p><p>Because the surface and interior of our planet are linked by tectonic processes, the linked evolution of the biosphere and sedimentary rocks should be recorded as a near-contemporary shift in the composition of the continental crust. To test this hypothesis, University of Southampton researchers assessed the isotopic signatures of zircons formed at subduction zones where marine sediments are transported into the mantle.</p><p><br />The Southampton researchers, led by Dr Tom Gernon, working with Queen's University Canada, led by Dr Christopher Spencer, and colleagues at the University of Cambridge, the University of Aberdeen, and the China University of Geosciences, Wuhan, studied the effects of land plant evolution on Earth's chemical composition over the past 700 million years.<br /><br />The researchers' findings are published in the journal Nature Geoscience.<br /><br />The evolution of land plants took place about 430 million years ago during the Silurian Period, when North America and Europe were conjoined in a landmass called Pangaea.<br /><br />The proliferation of plants completely transformed Earth's biosphere -- those parts of the planet's surface where life thrives -- paving the way for the advent of dinosaurs about 200 million years later.<br /><div style="width:100%;margin: 0px auto">
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</div><br />"Plants caused fundamental changes to river systems, bringing about more meandering rivers and muddy floodplains, as well as thicker soils," says Dr Christopher Spencer, Assistant Professor at Queen's University in Kingston, Ontario, lead author of the study. "This shift was tied to the development of plant rooting systems that helped produce colossal amounts of mud (by breaking down rocks) and stabilised river channels, which locked up this mud for long periods."<br /><br />The team recognised that Earth's surface and deep interior are linked by plate tectonics -- rivers flush mud into the oceans, and this mud then gets dragged into the Earth's molten interior (or mantle) at subduction zones where it gets melted to form new rocks.<br /><br />"When these rocks crystallise, they trap in vestiges of their past history," says Dr Tom Gernon, Associate Professor of Earth Science at the University of Southampton and co-author of the study. "So, we hypothesised that the evolution of plants should dramatically slow down the delivery of mud to the oceans, and that this feature should be preserved in the rock record -- it's that simple."<br /><br />To test this idea, the team studied a database of over five thousand zircon crystals formed in magmas at subduction zones -- essentially 'time capsules' that preserve vital information on the chemical conditions that prevailed on Earth when they crystallised.<br /><br />The team uncovered compelling evidence for a dramatic shift in the composition of rocks making up Earth's continents, which coincides almost precisely with the onset of land plants.<br /><br />Notably, the scientists also found that the chemical characteristics of zircon crystals generated at this time indicate a significant slowing down of sediment transfer to the oceans, just as they had hypothesised.<br /><br />The researchers show that vegetation changed not only the surface of the Earth, but also the dynamics of melting in Earth's mantle.<br /><br />"It is amazing to think that the greening of the continents was felt in the deep Earth," concludes Dr Spencer.<br /><br />"Hopefully this previously unrecognised link between the Earth's interior and surface environment stimulates further study."</p><p> </p><p><u><i><span style="font-family: trebuchet;"> The above story is based on <span style="color: black;"><a href="https://www.southampton.ac.uk/news/2022/08/land-plants-changed-earths-composition.page" rel="noopener noreferrer nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; 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; 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://www.southampton.ac.uk/" rel="noopener noreferrer nofollow" style="-webkit-text-stroke-width: 0px; background-color: white; border-radius: 0px !important; box-sizing: border-box; font-size: 14px; font-variant-caps: normal; font-variant-ligatures: normal; font-weight: 400; letter-spacing: normal; outline: currentcolor none 0px; 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 style="-webkit-text-stroke-width: 0px; background-color: white; 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></span></i></u></p>

Emergence of Land Plants Altered Composition of Earth’s Continental Crust

Schematic model of fluvial systems both before and after the development of land plants: before the Devonian period, minimal land plants, ra...

New Field of Research: Crystal Traces in Fossil Leaves

Fossils, Geology 9:17 PM

<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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhiWv3lghPW7K1M6F4tpP9G_P_VWAUC1nHxNNZXZ5RP4N8uYRilGKdzbp4L8QAKocHIEV-njGXfMgCHvpfztBnLR4l-jco0OQ4mB_4RMPcn0-CcnCYpgPIigucfeBbp73ZtUJyXKWRzyGW0FpW7UYjXEImaGi0NE8HbvyGH_MaNQYKUEWxXCM5dTvSD/s1203/New%20Field%20of%20Research%20Crystal%20Traces%20in%20Fossil%20Leaves%20(1).jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="800" data-original-width="1203" height="426" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhiWv3lghPW7K1M6F4tpP9G_P_VWAUC1nHxNNZXZ5RP4N8uYRilGKdzbp4L8QAKocHIEV-njGXfMgCHvpfztBnLR4l-jco0OQ4mB_4RMPcn0-CcnCYpgPIigucfeBbp73ZtUJyXKWRzyGW0FpW7UYjXEImaGi0NE8HbvyGH_MaNQYKUEWxXCM5dTvSD/w640-h426/New%20Field%20of%20Research%20Crystal%20Traces%20in%20Fossil%20Leaves%20(1).jpg" title="Busycon fossil snail shell geode lined with yellowish calcite crystals from the Quaternary of Florida, USA Photo: James St. John" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Busycon fossil snail shell geode lined with yellowish calcite crystals from the Quaternary of Florida, USA. Photo: James St. John</td></tr></tbody></table> <br /></p><p style="text-align: left;">In fossil leaves, puzzling structures are often visible under the microscope. Researchers at the University of Bonn have now been able to show for the first time that they originate from calcium oxalate crystals. On the one hand, their discovery facilitates the identification of the ancient plant remains. But it also provides answers as to how the ability to form such crystals arose and what function they presumably perform. The results have now been published in the journal Nature Scientific Reports.<br /><br />Fossil specimen Ro-59.9 is littered with microscopic cavities. Some of them look as if tiny raspberries had once slumbered inside them, each of them just two hundredths of a millimeter in size. The fossilized leaf comes from the Rott fossil site near Bonn and is more than 20 million years old. At the moment, it is not possible to say to which plant species it belongs.<br /><br />Perhaps that will change soon. Because the position and shape of the cavities are like a kind of fingerprint: they can be used to identify fossil plant remains. "Until now, it was not known how these cavities were formed," explains Mahdieh Malekhosseini from the Institute of Geosciences at the University of Bonn. "For example, it was believed that they came from algae or pollen from other plants that somehow got onto the leaf during fossilization. But after analyzing hundreds of these structures, we can rule that out. Instead, we were able to show that calcium oxalate crystals are responsible for the depressions."<br /></p><h4 style="text-align: left;"><span style="font-family: georgia;">Microlenses for better photosynthesis?</span></h4><p style="text-align: left;">Calcium oxalate is formed by very many living plants; it is considered one of the most common biominerals. What functions it fulfills has not yet been conclusively clarified. However, it is suspected that the crystals serve as calcium stores. In addition, because they are formed in the leaf but often penetrate the leaf surface as they grow, they probably repel pests. "Many insects have an aversion to calcium oxalate - they don't like to walk on it," explains Prof. Dr. Jes Rust, who supervised the study. "Some plants also seem to use the crystals as microlenses to use sunlight more efficiently for photosynthesis."<br /><br />The crystals are very sensitive to acid. They therefore dissolve during fossilization and can no longer be detected in the millions of years old finds. Often, however, imprints remain in the places where they have sat (in biology one speaks of "druses"). Sometimes organic material or other minerals also accumulate in these depressions, which then sit like tiny beads in the fossil leaf.<br /><br />"We studied the microstructure of the pits and their distribution on fossil leaves whose species affiliation we knew," Malekhosseini explains. "In addition, we looked at calcium oxalate crystals in the leaves of present-day plants. We found clear parallels in closely related species. For example, the crystal imprints in a fossil ginkgo leaf strongly resemble the calcium oxalate deposits of a present-day ginkgo in distribution and structure."<br /></p><h4 style="text-align: left;"><span style="font-family: georgia;">Important insights into evolution</span></h4><p style="text-align: left;">It was already known from the fossils of bare-seeded plants such as firs or pines that they sometimes show imprints of calcium oxalate crystals. However, this was not known of angiosperms - which are most flowers and deciduous trees. "This is a completely new field of research," explains Jes Rust. "Among other things, we now want to investigate how the ability to form calcium oxalate crystals has developed over the course of evolution." In doing so, the researchers want to focus on periods when environmental conditions changed rapidly - such as temperature or the intensity of UV radiation. "If the distribution of the drusen also changes after such incisions, then we can draw conclusions about the biological function of the crystals," says Rust.<br /><br /> </p><p style="text-align: left;"><u><i><span style="font-family: trebuchet;">The above story is based on <em style="-webkit-text-stroke-width: 0px; background-color: white; box-sizing: border-box; font-size: 15px; 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><a href="https://www.uni-bonn.de/en/news/216-2022" style="background-color: transparent; box-sizing: border-box; outline: currentcolor none medium;">materials</a><span> </span>provided by<span> </span><a href="https://www.uni-bonn.de/en" style="background-color: transparent; box-sizing: border-box;">University of Bonn</a>.</em></span></i></u> </p>

New Field of Research: Crystal Traces in Fossil Leaves

Busycon fossil snail shell geode lined with yellowish calcite crystals from the Quaternary of Florida, USA. Photo: James St. John In fossi...

Scientists Find Evidence of "Ocean" Hundreds of Miles Below Earth's Surface

Earth News, Geology, Tectonic, water 8:12 PM

<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://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi_Upxe4njFAaTS2iDZSYctgk6qEdy7y95945yMTONUe5X6AuBxYUqlEi0tOUFXt_B4Y0s4We4Vfd88RQPYKEseD2K8kg4gGyXO6CH1Wiw9FX7k0kxo4AYYkfV_RLbpI29lJSD-xMNXh5_-8ts8Ry-2u4ZwOIU8Z5Qu5XfRVvVhdsqz8jhX6objvi6B/s1213/Pearson_et_al_Earth_cross_section_Juina-12hg0rf-e1463952110730%20(1).jpg" style="margin-left: auto; margin-right: auto;"><img alt="Scientists Find Evidence of "Ocean" Hundreds of Miles Below Earth's Surface" border="0" data-original-height="949" data-original-width="1213" height="500" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi_Upxe4njFAaTS2iDZSYctgk6qEdy7y95945yMTONUe5X6AuBxYUqlEi0tOUFXt_B4Y0s4We4Vfd88RQPYKEseD2K8kg4gGyXO6CH1Wiw9FX7k0kxo4AYYkfV_RLbpI29lJSD-xMNXh5_-8ts8Ry-2u4ZwOIU8Z5Qu5XfRVvVhdsqz8jhX6objvi6B/w640-h500/Pearson_et_al_Earth_cross_section_Juina-12hg0rf-e1463952110730%20(1).jpg" title="Mantle Has an Ocean’s Worth of Water" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Scientists Find Evidence of "Ocean" Hundreds of Miles Below Earth's Surface. Cross section of the planet Earth ( Pearson et al,). Credit image: Kathy Mather.<br /></td></tr></tbody></table> <br /><p></p><p><span style="font-family: georgia;">Researchers say they've found new evidence of an "ocean" deep inside the Earth.</span><br /></p><p>After analyzing an extremely rare diamond believed to have been formed at a depth of around 410 miles below Botswana, an international team of researchers concluded in a new study published in the journal <i>Nature Geoscience</i> that the boundary between our planet's upper and lower mantle — a region known as the transition zone, which reaches hundreds of miles into the Earth's interior — holds far more trapped water and carbon dioxide than previously thought.<br /><br />The transition zone (TZ) is the name given to the boundary layer that separates the Earth's upper mantle and the lower mantle. It is located at a depth of 410 to 660 kilometres. The immense pressure of up to 23,000 bar in the TZ causes the olive-green mineral olivine, which constitutes around 70 percent of the Earth's upper mantle and is also called peridot, to alter its crystalline structure. At the upper boundary of the transition zone, at a depth of about 410 kilometres, it is converted into denser wadsleyite; at 520 kilometres it then metamorphoses into even denser ringwoodite.<br /><br />"These mineral transformations greatly hinder the movements of rock in the mantle," explains Prof. Frank Brenker from the Institute for Geosciences at Goethe University in Frankfurt. For example, mantle plumes -- rising columns of hot rock from the deep mantle -- sometimes stop directly below the transition zone. The movement of mass in the opposite direction also comes to standstill. Brenker says, "Subducting plates often have difficulty in breaking through the entire transition zone. So there is a whole graveyard of such plates in this zone underneath Europe."<br /><br />However, until now it was not known what the long-term effects of "sucking" material into the transition zone were on its geochemical composition and whether larger quantities of water existed there. Brenker explains: "The subducting slabs also carry deep-sea sediments piggy-back into the Earth's interior. These sediments can hold large quantities of water and CO<sub>2</sub>   . <br /></p><div style="margin: 0px auto; width: 100%;">
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</div><br /><p></p><p>But until now it was unclear just how much enters the transition zone in the form of more stable, hydrous minerals and carbonates -- and it was therefore also unclear whether large quantities of water really are stored there."<br /><br />The prevailing conditions would certainly be conducive to that. The dense minerals wadsleyite and ringwoodite can (unlike the olivine at lesser depths) store large quantities of water- in fact so large that the transition zone would theoretically be able to absorb six times the amount of water in our oceans. "So we knew that the boundary layer has an enormous capacity for storing water," Brenker says. "However, we didn't know whether it actually did so."<br /><br />An international study in which the Frankfurt geoscientist was involved has now supplied the answer. The research team analysed a diamond from Botswana, Africa. It was formed at a depth of 660 kilometres, right at the interface between the transition zone and the lower mantle, where ringwoodite is the prevailing mineral. Diamonds from this region are very rare, even among the rare diamonds of super-deep origin, which account for only one percent of diamonds. The analyses revealed that the stone contains numerous ringwoodite inclusions -- which exhibit a high water content. </p><p>Furthermore, the research group was able to determine the chemical composition of the stone. It was almost exactly the same as that of virtually every fragment of mantle rock found in basalts anywhere in the world. This showed that the diamond definitely came from a normal piece of the Earth's mantle. "In this study we have demonstrated that the transition zone is not a dry sponge, but holds considerable quantities of water," Brenker says, adding: "This also brings us one step closer to Jules Verne's idea of an ocean inside the Earth." The difference is that there is no ocean down there, but hydrous rock which, according to Brenker, would neither feel wet nor drip water.<br /><br />Hydrous ringwoodite was first detected in a diamond from the transition zone as early as 2014. Brenker was involved in that study, too. However, it was not possible to determine the precise chemical composition of the stone because it was too small. It therefore remained unclear how representative the first study was of the mantle in general, as the water content of that diamond could also have resulted from an exotic chemical environment. By contrast, the inclusions in the 1.5 centimetre diamond from Botswana, which the research team investigated in the present study, were large enough to allow the precise chemical composition to be determined, and this supplied final confirmation of the preliminary results from 2014.<br /><br />The transition zone's high water content has far-reaching consequences for the dynamic situation inside the Earth. What this leads to can be seen, for example, in the hot mantle plumes coming from below, which get stuck in the transition zone. There, they heat up the water-rich transition zone, which in turn leads to the formation of new smaller mantle plumes that absorb the water stored in the transition zone. If these smaller water-rich mantle plumes now migrate further upwards and break through the boundary to the upper mantle, the following happens: The water contained in the mantle plumes is released, which lowers the melting point of the emerging material. It therefore melts immediately and not just before it reaches the surface, as usually happens. As a result, the rock masses in this part of the Earth's mantle are no longer as tough overall, which gives the mass movements more dynamism. The transition zone, which otherwise acts as a barrier to the dynamics there, suddenly becomes a driver of the global material circulation.<br /></p><p><br /><u><i><span style="font-family: trebuchet;">The above story is based on <a href="https://aktuelles.uni-frankfurt.de/englisch/an-ocean-inside-the-earth-water-hundreds-of-kilometres-down/" rel="noopener noreferrer 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="https://www.goethe-university-frankfurt.de/en" rel="noopener noreferrer 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;">Goethe University Frankfurt</b></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></i></u></p>

Scientists Find Evidence of "Ocean" Hundreds of Miles Below Earth's Surface

Scientists Find Evidence of "Ocean" Hundreds of Miles Below Earth's Surface. Cross section of the planet Earth ( Pearson et al...

Remarkable 380-Million-Year-Old Heart Discovered

evolution, Fossils 8:46 PM

<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMysNqg7W3u5z0E0taKzMtD5HcmNuli6N230B6TQg_a579lyiSSLPhK0efLe7B5EdWToEC8xmNdqw-3N28xEKlNGB4GzGYpGidaewBUEkklTP1QpphfX9qU9ksZNHk92JRp3O9UqLk-pd6s1whHSBJTsA0FTxQ-5oW8IYhNsNpv3vka7Q3c_j2ZogV/s1225/Remarkable%20380-Million-Year-Old%20Heart%20Discovered%20(1).jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="919" data-original-width="1225" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMysNqg7W3u5z0E0taKzMtD5HcmNuli6N230B6TQg_a579lyiSSLPhK0efLe7B5EdWToEC8xmNdqw-3N28xEKlNGB4GzGYpGidaewBUEkklTP1QpphfX9qU9ksZNHk92JRp3O9UqLk-pd6s1whHSBJTsA0FTxQ-5oW8IYhNsNpv3vka7Q3c_j2ZogV/w640-h480/Remarkable%20380-Million-Year-Old%20Heart%20Discovered%20(1).jpg" title="Remarkable 380-Million-Year-Old Heart Discovered" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">The Gogo Fish Fossil Where the 380-million-year-old, 3d Preserved Heart Was Discovered by Researchers. Pictured at the Wa Museum. Credit: Yasmine Phillips, Curtin University</td></tr></tbody></table><p>Researchers have discovered a 380-million-year-old heart -- the oldest ever found -- alongside a separate fossilised stomach, intestine and liver in an ancient jawed fish, shedding new light on the evolution of our own bodies.<br /><br />The new research, published today in Science, found that the position of the organs in the body of arthrodires -- an extinct class of armoured fishes that flourished through the Devonian period from 419.2 million years ago to 358.9 million years ago -- is similar to modern shark anatomy, offering vital new evolutionary clues.<br /><br />Lead researcher John Curtin Distinguished Professor Kate Trinajstic, from Curtin's School of Molecular and Life Sciences and the Western Australian Museum, said the discovery was remarkable given that soft tissues of ancient species were rarely preserved and it was even rarer to find 3D preservation.<br /><br />"As a palaeontologist who has studied fossils for more than 20 years, I was truly amazed to find a 3D and beautifully preserved heart in a 380-million-year-old ancestor," Professor Trinajstic said.<br /><br />"Evolution is often thought of as a series of small steps, but these ancient fossils suggest there was a larger leap between jawless and jawed vertebrates. These fish literally have their hearts in their mouths and under their gills -- just like sharks today."<br /><br />This research presents -- for the first time -- the 3D model of a complex s-shaped heart in an arthrodire that is made up of two chambers with the smaller chamber sitting on top.<br /><br />Professor Trinajstic said these features were advanced in such early vertebrates, offering a unique window into how the head and neck region began to change to accommodate jaws, a critical stage in the evolution of our own bodies.<br /><br />"For the first time, we can see all the organs together in a primitive jawed fish, and we were especially surprised to learn that they were not so different from us," Professor Trinajstic said.<br /><br />"However, there was one critical difference -- the liver was large and enabled the fish to remain buoyant, just like sharks today. Some of today's bony fish such as lungfish and birchers have lungs that evolved from swim bladders but it was significant that we found no evidence of lungs in any of the extinct armoured fishes we examined, which suggests that they evolved independently in the bony fishes at a later date."<br /><br />The Gogo Formation, in the Kimberley region of Western Australia where the fossils were collected, was originally a large reef.<br /><br />Enlisting the help of scientists at the Australian Nuclear Science and Technology Organisation in Sydney and the European Synchrotron Radiation Facility in France, researchers used neutron beams and synchrotron x-rays to scan the specimens, still embedded in the limestone concretions, and constructed three-dimensional images of the soft tissues inside them based on the different densities of minerals deposited by the bacteria and the surrounding rock matrix.<br /><br />This new discovery of mineralised organs, in addition to previous finds of muscles and embryos, makes the Gogo arthrodires the most fully understood of all jawed stem vertebrates and clarifies an evolutionary transition on the line to living jawed vertebrates, which includes the mammals and humans.<br /><br />Co-author Professor John Long, from Flinders University, said: "These new discoveries of soft organs in these ancient fishes are truly the stuff of palaeontologists' dreams, for without doubt these fossils are the best preserved in the world for this age. They show the value of the Gogo fossils for understanding the big steps in our distant evolution. Gogo has given us world firsts, from the origins of sex to the oldest vertebrate heart, and is now one of the most significant fossil sites in the world. It's time the site was seriously considered for world heritage status."<br /><br />Co-author Professor Per Ahlberg, from Uppsala University, said: "What's really exceptional about the Gogo fishes is that their soft tissues are preserved in three dimensions. Most cases of soft-tissue preservation are found in flattened fossils, where the soft anatomy is little more than a stain on the rock. We are also very fortunate in that modern scanning techniques allow us to study these fragile soft tissues without destroying them. A couple of decades ago, the project would have been impossible."</p><p> </p><p><i><u><span style="font-family: trebuchet;"> The above story is based on <a href="https://news.curtin.edu.au/media-releases/new-curtin-led-research-discovers-the-heart-of-our-evolution/" rel="noopener noreferrer 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://www.curtin.edu.au/" rel="noopener noreferrer 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;">Curtin 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;">.</span></span></u></i></p>

Remarkable 380-Million-Year-Old Heart Discovered

The Gogo Fish Fossil Where the 380-million-year-old, 3d Preserved Heart Was Discovered by Researchers. Pictured at the Wa Museum. Credit: Ya...

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