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  • richardmitnick 12:10 pm on November 19, 2021 Permalink | Reply
    Tags: "Scientists Identify New Force Behind Past Mass Extinction Event", , , , , Paleogeology   

    From New York University (US): “Scientists Identify New Force Behind Past Mass Extinction Event” 

    NYU BLOC

    From New York University (US)

    Nov 17, 2021

    James Devitt
    james.devitt@nyu.edu
    (212) 998-6808

    A team of scientists has identified an additional force that likely contributed to a mass extinction event 250 million years ago.

    “Volcanic Winter” Likely Contributed to Ecological Catastrophe 250 Million Years Ago.

    1
    A team of scientists has identified an additional force that likely contributed to a mass extinction event 250 million years ago by examining mineral and related deposits on land in the south China region, including those found in the Yunnan province. Photo credit: Tim Bennett/Getty Images.

    A team of scientists has identified an additional force that likely contributed to a mass extinction event 250 million years ago. Its analysis of minerals in southern China indicate that volcano eruptions produced a “volcanic winter” that drastically lowered earth’s temperatures–a change that added to the environmental effects resulting from other phenomena at the time.

    The research, which appears in the journal Science Advances, examined the end-Permian mass extinction (EPME), which was the most severe extinction event in the past 500 million years, wiping out 80 to 90 percent of species on land and in the sea.

    “As we look closer at the geologic record at the time of the great extinction, we are finding that the end-Permian global environmental disaster may have had multiple causes among marine and non-marine species,” says Michael Rampino, a professor in New York University’s Department of Biology and one of the authors of the paper.

    For decades, scientists have investigated what could have caused this global ecological catastrophe, with many pointing to the spread of vast floods of lava across what is known as the Siberian Traps–a large region of volcanic rock in the Russian province of Siberia. These eruptions caused environmental stresses, including severe global warming from volcanic releases of carbon dioxide and related reduction in oxygenation of ocean waters–the latter causing the suffocation of marine life.

    The team for the Science Advances work, composed of more than two dozen researchers, including scientists from China’s Nanjing University [南京大學] (CN) and Guangzhou Institute of Geochemistry at The Chinese Academy of Sciences [中国科学院] (CN) as well as The Smithsonian National Museum of Natural History (US) and The Montclair State University (US), considered other factors that may have contributed to the end of the Permian Period, which stretched from 300 million to 250 million years ago.

    Specifically, they found mineral and related deposits on land in the south China region–notably copper and mercury–whose age coincided with the end-Permian mass extinction in non-marine localities. Specifically, these deposits were marked by anomalies in their composition likely due to sulfur-rich emissions from nearby volcanic eruptions–they were covered by layers of volcanic ash.

    2
    Copper-rich minerals indicating widespread volcanic activity at the end-Permian mass extinction in different regions in southern China (A: Taoshujing locality; B: Lubei locality; C: Guanbachong; D: Taoshujing locality; E: Longmendong locality). The minerals are all copper sulfides, mostly Malachite–the minerals’ green patches. Photo credit: H. Zhang, Nanjing Institute of Geology and Palaeontology.

    “Sulfuric acid atmospheric aerosols produced by the eruptions may have been the cause of rapid global cooling of several degrees, prior to the severe warming seen across the end-Permian mass-extinction interval,” explains Rampino.

    The team’s findings suggested that the Siberian Traps eruptions were not the sole cause of the end-Permian mass extinction, and that the environmental effects of the eruptions in South China, and elsewhere, may have played a vital role in the disappearance of dozens of species.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    NYU Campus

    More than 175 years ago, Albert Gallatin, the distinguished statesman who served as secretary of the treasury under Presidents Thomas Jefferson and James Madison, declared his intention to establish “in this immense and fast-growing city … a system of rational and practical education fitting for all and graciously opened to all.” Founded in 1831, New York University (US) is now one of the largest private universities in the United States. Of the more than 3,000 colleges and universities in America, New York University is one of only 60 member institutions of the distinguished Association of American Universities (US).

    New York University (NYU) (US) is a private research university in New York City. Chartered in 1831 by the New York State Legislature, NYU was founded by a group of New Yorkers led by then Secretary of the Treasury Albert Gallatin.

    In 1832, the initial non-denominational all-male institution began its first classes near City Hall based on a curriculum focused on a secular education. The university, in 1833, then moved and has maintained its main campus in Greenwich Village surrounding Washington Square Park. Since then, the university has added an engineering school in Brooklyn’s MetroTech Center and graduate schools throughout Manhattan. NYU has become the largest private university in the United States by enrollment, with a total of 51,848 enrolled students, including 26,733 undergraduate students and 25,115 graduate students, in 2019. NYU also receives the most applications of any private institution in the United States and admissions is considered highly selective.

    NYU is organized into 10 undergraduate schools, including the College of Arts & Science, Gallatin School, Steinhart School, Stern School of Business, Tandon School of Engineering, and the Tisch School of Arts. NYU’s 15 graduate schools includes the Grossman School of Medicine, School of Law, Wagner Graduate School of Public Service, School of Professional Studies, School of Social Work, Rory Meyers School of Nursing, and Silver School of Social Work. The university’s internal academic centers include the Courant Institute of Mathematical Sciences, Center for Data Science, Center for Neural Science, Clive Davis Institute, Institute for the Study of the Ancient World, Institute of Fine Arts, and the NYU Langone Health System. NYU is a global university with degree-granting campuses at NYU Abu Dhabi and NYU Shanghai, and academic centers in Accra, Berlin, Buenos Aires, Florence, London, Los Angeles, Madrid, Paris, Prague, Sydney, Tel Aviv, and Washington, D.C.

    Past and present faculty and alumni include 38 Nobel Laureates, 8 Turing Award winners, 5 Fields Medalists, 31 MacArthur Fellows, 26 Pulitzer Prize winners, 3 heads of state, a U.S. Supreme Court justice, 5 U.S. governors, 4 mayors of New York City, 12 U.S. Senators, 58 members of the U.S. House of Representatives, two Federal Reserve Chairmen, 38 Academy Award winners, 30 Emmy Award winners, 25 Tony Award winners, 12 Grammy Award winners, 17 billionaires, and seven Olympic medalists. The university has also produced six Rhodes Scholars, three Marshall Scholars, 29 Schwarzman Scholars, and one Mitchell Scholar.

    Research

    NYU is classified among “R1: Doctoral Universities – Very high research activity” and research expenditures totaled $917.7 million in 2017. The university was the founding institution of the American Chemical Society. The NYU Grossman School of Medicine received $305 million in external research funding from the National Institutes of Health (US) in 2014. NYU was granted 90 patents in 2014, the 19th most of any institution in the world. NYU owns the fastest supercomputer in New York City. As of 2016, NYU hardware researchers and their collaborators enjoy the largest outside funding level for hardware security of any institution in the United States, including grants from the National Science Foundation (US), the Office of Naval Research (US), the Defense Advanced Research Projects Agency (US), the United States Army Research Laboratory (US), the Air Force Research Laboratory (US), the Semiconductor Research Corporation, and companies including Twitter, Boeing, Microsoft, and Google.

    In 2019, four NYU Arts & Science departments ranked in Top 10 of Shanghai Academic Rankings of World Universities by Academic Subjects (Economics, Politics, Psychology, and Sociology).

     
  • richardmitnick 10:59 am on November 12, 2021 Permalink | Reply
    Tags: "A Simple Recipe for Making the First Continental Crust", , , , , Paleogeology   

    From Eos: “A Simple Recipe for Making the First Continental Crust” 

    From AGU
    Eos news bloc

    From Eos

    5 November 2021
    Anastassia Y. Borisova
    Anne Nédélec

    Laboratory experiments serendipitously revealed a rock-forming process that might explain how the first continental crust formed on Earth—and possibly on Mars.

    1
    During the Hadean eon, more than 4 billion years ago, a liquid water ocean, volcanic activity, and meteorite impacts acted together to fashion the surface of early Earth. Credit: Anastassia Borisova.

    Earth’s continental crust, on which billions of people and countless land animals and plants spend their lives, is distinguished by its predominantly felsic composition. That is, this crust contains large proportions of silicon, oxygen, aluminum, and alkali metals like sodium and potassium, and it is largely made up of quartz and feldspar minerals. Felsic continental crust as old as 4 billion years has been recognized on Earth’s surface, and we know it was associated with basaltic oceanic crust made of minerals rich in calcium, magnesium, and iron, such as plagioclase feldspar, olivine, and pyroxenes. But the planet’s earliest rigid outer shell—its primordial crust, which crystallized from the magma ocean covering the nascent Earth about 4.5 billion years ago—probably looked very different.

    When and how the first felsic crust formed are questions researchers have pondered for decades. Unfortunately, a handful of microscopic zircons, accessory minerals commonly found in felsic rocks, from a few places around the world are the only remnants from the Hadean eon, the first 500 million years of Earth’s existence. In the almost complete absence of early crustal rocks, scientists have thus had to piece together their hypotheses from indirect evidence.

    Recently, our research group completed laboratory experiments and numerical modeling that revealed evidence of a felsic rock-forming reaction that may have occurred on Hadean Earth and may have been responsible for creating the planet’s first continental crust.

    Continental Crust Through the Ages

    Present-day continental crust is formed by magmatism at volcanic arcs above subduction zones, like the Aleutian Arc off Alaska, the Izu-Bonin-Mariana Arc in the western Pacific, and the Andes in South America. As water in a subducting oceanic slab (crust and mantle) is driven off by the high heat at depth (50–100 kilometers below the surface), it promotes partial melting of overlying mantle rocks (e.g., peridotites). The buoyant melt then rises to the surface, where it interacts with existing crust, cools, and solidifies underground or erupts from volcanoes. The result is new continental crust of dioritic to tonalitic composition. This process has operated efficiently for at least the past 2.5 billion years.

    Before that, in the Archean (starting 4 billion years ago), when Earth was hotter, continental crust formed directly from partial melting of hydrated oceanic crust in “vertical drips” of basaltic crust before the beginning of plate tectonics around 3.2 billion years ago or in warm subduction zones afterward [e.g., Shirey and Richardson, 2011; Gerya, 2019*]. Archean continental crust is made of tonalites, trondhjemites, and granodiorites (TTG): felsic rocks with a higher sodium content than modern continental crust. However, the nature and genesis of continental crust in Earth’s most remote past—during the Hadean, more than 4 billion years ago—are a mystery.

    *All citations are in References below with links.

    Many hypotheses have been suggested to explain the formation of felsic, zircon-bearing crust in the Hadean, although so far none have been sufficiently convincing. Some researchers favor a Hadean context in which felsic crust formation was very similar to that on modern Earth [Harrison, 2020], whereas others think that it resembled processes occurring in the Archean. All of these researchers have assumed that the parental magmas of the Hadean zircons formed at depths of 30–50 kilometers from protolith (sediments or a basaltic protocrust) that had previously interacted with liquid water [e.g., Drabon et al., 2021].

    Faltys and Wielicki [2020] suggested a crucial role of meteorite impact–induced magmatism in the formation of the first felsic continental crust. However, in most cases, a role for early plate tectonics is assumed, even though evidence from geochemical and geodynamic modeling studies suggests that modern-style plate tectonics did not begin until about 3.2 billion years ago.

    An Unintended Discovery

    Our research group did not set out to establish how the first continental crust formed. Instead, we were studying interactions among solid rock, magma, and fluids under the ocean to explain the origin of the oceanic mantle-crust transition boundary and adjacent upper mantle rocks (chromitite, dunite, and hydrated peridotites (i.e., serpentinite)). This transition boundary plays a crucial role in controlling the chemical composition and physical properties of oceanic magmatism and crust.

    Nail Zagrtdenov, a doctoral student in the Géosciences Environnement Toulouse laboratory at the University of Toulouse III in France, was leading laboratory experiments under the supervision of Anastassia Y. Borisova and Michael J. Toplis. These experiments were designed to replicate the shallow conditions and processes happening at the mantle-crust boundary about 6 kilometers beneath present-day oceanic spreading centers.

    In these experiments, we examined interactions between basaltic melts and different proportions of serpentinite rock at temperatures of 1,250°C–1,300°C and pressures of 0.1 to 0.2 gigapascal [Borisova et al., 2021a, 2021b]. Serpentinite, which commonly forms at oceanic ridges, is formed by hydrothermal alteration of peridotite, an ultramafic rock that makes up most of Earth’s upper mantle.

    Our experimental results surprised us. As expected, we saw chromitite and dunite form at 0.2 gigapascal. However, we also observed felsic melts—the starting material for continental crust—forming amid the dense, dark, olivine-rich serpentinized peridotite. Production of felsic melts from hydrated peridotites at such shallow conditions was a novel observation, and we began to think that we had unintentionally reproduced conditions that were prevalent more than 4 billion years ago. Perhaps we had stumbled onto the explanation for the formation of early felsic crust.

    To investigate further, we followed up our experiments by simulating the same conditions using thermodynamic numerical modeling. This modeling confirmed that felsic melts could be produced from the same starting materials and remain stable at pressures of 0.1 to 0.2 gigapascal (3–6 kilometers depth). With the combined laboratory and modeling results, our multidisciplinary team of French, German, American, and Russian researchers became convinced we had established the ingredients and the physical and chemical conditions necessary to form the very first felsic crust on Earth—and possibly on Mars [Borisova et al., 2021a].

    A New Model for Early Crust

    Publishing our data and interpretations was rather difficult. Indeed, these results were entirely new, and some researchers were skeptical. Most previous hypotheses had proposed that the first continental crust resembled either present-day continental crust or Archean continental crust in terms of its formation processes and conditions. The conditions and ingredients of our experiments, and the felsic melts they produced, suggest a completely different scenario.

    Our model posits that liquid water existed on early Earth’s surface [Valley et al., 2002]. The idea that the protolith of the magmas from which Hadean zircons crystallized had previously interacted with liquid water is accepted on the basis of oxygen isotope data from these zircons [Mojzsis et al., 2001]. However, considering hydrated peridotite as a possible protolith is a novel suggestion (Figure 1).

    1
    Fig. 1. In a new model for the production of Hadean felsic crust, serpentinite (green) submerged under water (blue) comes into contact with basaltic magma (yellow). This interaction produces felsic magmas (red) with accessory zircon crystals (white crystals) in association with olivine-rich peridotite (light brown). Frequent meteorite impacts in the Hadean could have aided in the mixing and interaction between the hydrated peridotite and basalt in the presence of water fluid, triggering the production of the first zircon-bearing continental crust.

    The young planet’s magma ocean would have had the same peridotitic composition as the mantle. As the magma ocean cooled and crystallized, a thin peridotite crust could have quenched atop the ocean while gases, including water vapor, were expelled from the magma. These gases would have built a primitive atmosphere, from which liquid water would have condensed to the hydrosphere. The primitive peridotitic crust would have rapidly interacted with the liquid water, yielding serpentinites [Albarède and Blichert-Toft, 2007]. This possibility has not received much consideration from researchers, who typically assume the Hadean protocrust was basaltic, comparable to the present-day surfaces of asteroids and protoplanets.

    In our model, basaltic magmas would have formed as the last differentiate liquids remaining at the very end of the crystallization of the magma ocean, and then they would have locally intruded and mixed into the uppermost serpentinized crust. Interaction between magma and protocrust material would have caused dehydration of the serpentinized peridotite. Afterward, the peridotite would have partially melted to produce felsic melts at shallow depth—as we observed in our experiments. These melts would have then cooled to form the first felsic crust (Figure 1). Frequent meteorite impacts in the Hadean could have aided in this mixing and interaction by fracturing, heating, and promoting water convection through and partial melting of the protocrust.

    2
    Plagiogranite veins and intrusions from Earth’s mantle appear as white streaks amid brown serpentinized peridotite in a section of the Wadi Fizh, Semail ophiolite, Oman. Credit: Georges Ceuleneer.

    We see evidence of such felsic rock formation in the field. For example, felsic (plagiogranitic) rocks are exposed now amid hydrated peridotitic mantle rocks in the Semail ophiolite in Oman, which formed at a depth of less than 10 kilometers below the surface.

    Further Explorations

    The scenario of interacting serpentinized rocks and basaltic magmas offers a simple and efficient recipe that we believe explains the origin of Hadean felsic crust well for several reasons. First, it requires the existence of shallow liquid water on the early terrestrial surface (Figure 1). Second, it involves plausible shallow interactions between hydrated peridotite and basaltic melts resulting from shallow magmatism or impact-induced melting. Third, in agreement with existing geodynamic models for the Hadean, it does not require plate tectonics. Furthermore, our experimental felsic melts can crystallize low-temperature zircons very similar to observed detrital Hadean zircons [Borisova et al., 2021b].

    To further develop this model and understand the origins of the first planetary continental crust, we plan to conduct further experiments involving pressure gradients and shock process modeling. This work is necessary to explore mineral dehydration and melt channelization happening during shock processes, melt percolation, and reequilibration of the percolating melt with the hydrated peridotite. Such work should increase the applicability of our experimental results to phenomena occurring throughout the Hadean eon and will help develop our new model of primordial processes happening on early Earth and Mars.

    We are also planning new experiments to reproduce conditions on Mars and study whether our new results could relate to processes that happened on the neighboring planet. Like Earth, early Mars had water on its surface sometime after the crystallization of a primordial crust from a magma ocean. Importantly, the composition of our experimental felsic melts is similar to that of felsic rocks that Curiosity discovered on Mars [Sautter et al., 2015]. Thus, it seems worthwhile to compare conditions on the two planets.

    Current explorations of Mars may help validate and complement our hypothesis regarding the early evolution of water-bearing rocky planets. New seismic data from the InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) lander, coupled with crustal and thermal modeling based on InSight data, have provided new information on the depth and structure of the Martian crust [e.g., Knapmeyer-Endrun et al., 2021]. Analysis so far indicates that Mars’s relatively weak gravitational field, which is only about 40% as strong as Earth’s, suggests early felsic crust on the planet could have been located deeper than it was on Earth—at depths of 25–30 kilometers compared with the corresponding Hadean felsic crust generated less than 10 kilometers deep on Earth.

    There is much more to learn about early crust-forming processes and conditions on Earth—and Mars. But the mechanism described here may represent the most plausible idea yet of how large volumes of the first felsic crust were made, answering a decades-old question in Earth science.

    Acknowledgments

    Investigations of the mantle section of the Oman ophiolite are supported by Institut National des Sciences de l’Univers of the The National Centre for Scientific Research [Centre national de la recherche scientifique [CNRS](FR) under grant PLAGIOGRAN 2021-2023.

    References

    Albarède, F., and J. Blichert-Toft (2007), The split fate of the early Earth, Mars, Venus and Moon, C. R. Geosci., 339, 917–927, https://doi.org/10.1016/j.crte.2007.09.006.

    Borisova, A. Y., et al. (2021a), Hydrated peridotite – basaltic melt interaction. Part I: Planetary felsic crust formation at shallow depth, Front. Earth Sci., 9, 640464, https://doi.org/10.3389/feart.2021.640464.

    Borisova, A. Y., et al. (2021b), Hadean zircon formed due to hydrated ultramafic protocrust melting, Geology, doi:10.1130/G49354.1, in press.

    Drabon, N., et al. (2021), Heterogeneous Hadean crust with ambient mantle affinity recorded in detrital zircons of the Green Sandstone Bed, South Africa, Proc. Natl. Acad. Sci. U. S. A., 118, e2004370118, https://doi.org/10.1073/pnas.2004370118.

    Faltys, J. P., and M. M. Wielicki (2020), Inclusions in impact-formed zircon as a tracer of target rock lithology: Implications for Hadean continental crust composition and abundance, Lithos, 376–377, 105761, https://doi.org/10.1016/j.lithos.2020.105761.

    Gerya, T. (2019), Geodynamics of the early Earth: Quest for the missing paradigm, Geology, 47, 1,006–1,007, https://doi.org/10.1130/focus102019.1.

    Harrison T. M. (2020), Hadean Earth, Springer, Cham, Switzerland, https://doi.org/10.1007/978-3-030-46687-9.

    Knapmeyer-Endrun, B., et al. (2021), Thickness and structure of the Martian crust from InSight seismic data, Science, 373, 438–443, https://doi.org/10.1126/science.abf8966.

    Mojzsis, S. J., T. M. Harrison, and R. T. Pidgeon (2001), Oxygen-isotope evidence from ancient zircons for liquid water at the Earth’s surface 4,300 Myr ago, Nature, 409, 178–181, https://doi.org/10.1038/35051557.

    Sautter, V., et al. (2015), In situ evidence for continental crust on early Mars, Nat. Geosci., 3, 605–609, https://doi.org/10.1038/ngeo2474.

    Shirey, S. B., and S. H. Richardson (2011), Start of the Wilson cycle at 3 Ga shown by diamonds from subcontinental mantle, Science, 333, 434–436, https://doi.org/10.1126/science.1206275.

    Valley, J. W., et al. (2002), A cool early Earth, Geology, 30, 351–354, https://doi.org/10.1130/0091-7613(2002)0302.0.CO;2.

    See the full article here .

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    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 7:04 pm on September 28, 2021 Permalink | Reply
    Tags: "Geological cold case may reveal critical minerals", , Columbia-also known as Nuna or Hudsonland is thought to have existed approximately 2, Columbia-also known as Nuna or Hudsonland is thought to have existed approximately 2500 to 1500 million years ago in the Paleoproterozoic Era., , , Paleogeology,   

    From The University of Adelaide (AU) : “Geological cold case may reveal critical minerals” 

    u-adelaide-bloc

    From The University of Adelaide (AU)

    Sep 24 2021
    Crispin Savage

    Researchers on the hunt for why cold eclogites mysteriously disappeared from geological records during the early stages of the Earth’s development may have found the answer, and with it clues that could help locate critical minerals today.

    1
    Eclogite from Norway.

    “Cold eclogites mysteriously disappeared from the Earth’s rock record between 1.8 and 1.2 billion years ago before reappearing after this time,” said Dr Derrick Hasterok, Lecturer, Department of Earth Sciences, University of Adelaide.

    “Cold eclogites are important because they are sensitive to the temperatures in the upper mantle and provide evidence of rocks rapidly transported deep below Earth’s surface along geological faults lines that occur where tectonic plates collide.

    “The prevailing belief is that cold eclogites are preserved only when supercontinents merged. But there is ample evidence for a nearly continuous geological record of cold eclogites over the past 700 million years during which time two supercontinents formed and broke-up.”

    Eclogites are high-pressure, metamorphic rocks that consist primarily of garnet and omphacite (a sodium-rich variety of pyroxene).

    Associated with this change in eclogites is a change in the concentration of many trace elements in igneous rocks found elsewhere in the crust, which provide additional evidence of heating beneath continents. These trace elements are found in critical minerals. Critical minerals are considered vital for the economic well-being of the world’s major and emerging economies.

    Lead author Dr Renee Tamblyn worked with Dr Hasterok and fellow researchers Professor Martin Hand and PhD student Matthew Gard from the University of Adelaide on the study which was published in the journal Geology.

    “We found evidence from the trace element chemistry of granites that suggests a large-scale heating of the continents around 2 billion years ago that corresponds with the assembly of Nuna, a supercontinent which completed its formation 1.6 billion years ago,” said Dr Tamblyn.

    2
    Columbia, also known as Nuna or Hudsonland, was one of Earth’s ancient supercontinents. It was first proposed by Rogers & Santosh 2002[1] and is thought to have existed approximately 2,500 to 1,500 million years ago in the Paleoproterozoic Era. Zhao et al. 2002[2] proposed that the assembly of the supercontinent Columbia was completed by global-scale collisional events during 2.1–1.8 Ga.

    [1] Rogers, J. J.; Santosh, M. (2002). “Configuration of Columbia, a Mesoproterozoic supercontinent” (PDF).

    Columbia consisted of proto-cratons that made up the cores of the continents of Laurentia, Baltica, Ukrainian Shield, Amazonian Shield, Australia, and possibly Siberia, North China, and Kalaharia as well.

    The evidence of Columbia’s existence is based upon geological[2][3] and paleomagnetic data.[4]
    [2] https://en.wikipedia.org/wiki/Columbia_(supercontinent)#cite_note-Zhao1-abst-2
    [3] https://en.wikipedia.org/wiki/Columbia_(supercontinent)#cite_note-Zhao2-abst-3
    [4] https://en.wikipedia.org/wiki/Columbia_(supercontinent)#cite_note-Pesonen-Bispo-Santos-4

    “The Earth has generally been cooling since its formation but Nuna had an insulating effect on the mantle, rather like a thick blanket, which caused temperatures to rise beneath the continents and prevent the preservation of eclogites and change the chemistry of granites.

    “The changes in chemistry resulting from this unusual warming event during Earth’s geologic past could help to locate certain critical minerals by looking for rocks formed before or after this heating event – depending on which element is of being looked for.”

    Much of Western Australia is older than 2 billion years while South Australia and the eastern states are generally younger.

    “The rocks in the Northern Territory and NW Queensland are a little older than the 1.8 billion year mark so may be a place where we can continue our investigations into this mysterious geological case,” said Dr Hasterok.

    See the full article here.

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    u-adelaide-campus

    The University of Adelaide is a public research university located in Adelaide, South Australia. Established in 1874, it is the third-oldest university in Australia. The university’s main campus is located on North Terrace in the Adelaide city centre, adjacent to the Art Gallery of South Australia, the South Australian Museum and the State Library of South Australia.

    The university has four campuses, three in South Australia: North Terrace campus in the city, Roseworthy campus at Roseworthy and Waite campus at Urrbrae, and one in Melbourne, Victoria. The university also operates out of other areas such as Thebarton, the National Wine Centre in the Adelaide Park Lands, and in Singapore through the Ngee Ann-Adelaide Education Centre.

    The University of Adelaide is composed of five faculties, with each containing constituent schools. These include the Faculty of Engineering, Computer, and Mathematical Sciences (ECMS), the Faculty of Health and Medical Sciences, the Faculty of Arts, the Faculty of the Professions, and the Faculty of Sciences. It is a member of the Group of Eight and the Association of Commonwealth Universities. The university is also a member of the Sandstone universities, which mostly consist of colonial-era universities within Australia.

    The university is associated with five Nobel laureates, constituting one-third of Australia’s total Nobel Laureates, and 110 Rhodes scholars. The university has had a considerable impact on the public life of South Australia, having educated many of the state’s leading businesspeople, lawyers, medical professionals and politicians. The university has been associated with many notable achievements and discoveries, such as the discovery and development of penicillin, the development of space exploration, sunscreen, the military tank, Wi-Fi, polymer banknotes and X-ray crystallography, and the study of viticulture and oenology.

    Research

    The University of Adelaide is one of the most research-intensive universities in Australia, securing over $180 million in research funding annually. Its researchers are active in both basic and commercially oriented research across a broad range of fields including agriculture, psychology, health sciences, and engineering.

    Research strengths include engineering, mathematics, science, medical and health sciences, agricultural sciences, artificial intelligence, and the arts.

    The university is a member of Academic Consortium 21, an association of 20 research intensive universities, mainly in Oceania, though with members from the US and Europe. The university held the Presidency of AC 21 for the period 2011–2013 as host the biennial AC21 International Forum in June 2012.

    The Centre for Automotive Safety Research (CASR), based at the University of Adelaide, was founded in 1973 as the Road Accident Research Unit and focuses on road safety and injury control.
    Rankings

     
  • richardmitnick 9:45 am on September 4, 2021 Permalink | Reply
    Tags: "Ground-breaking work from SFU identifies new source for earthquakes and tsunamis in the Greater Tokyo Region", A previously unconsidered plate boundary, , In 2011 eastern Japan was hit with a massive magnitude 9 quake – creating the largest rupture area of any earthquake originating from the Japan Trench., Paleoecology, Paleogeology,   

    From Simon Fraser University (CA) : “Ground-breaking work from SFU identifies new source for earthquakes and tsunamis in the Greater Tokyo Region” 

    From Simon Fraser University (CA)

    September 02, 2021
    Diane Mar-Nicolle

    1
    Jessica Pilarczyk and colleagues from the Geological Survey of Japan core rice paddies on the Boso peninsula to uncover geological evidence for a tsunami from 1,000 years ago. Credit: SFU.

    Researchers have discovered geologic evidence that unusually large earthquakes and tsunamis from the Tokyo region—located near tectonic plate boundaries that are recognized as a seismic hazard source—may be traceable to a previously unconsidered plate boundary. The team, headed by Simon Fraser University Earth scientist Jessica Pilarczyk, has published its research today in Nature Geoscience.

    The team’s ground-breaking discovery represents a new and unconsidered seismic risk for Japan with implications for countries lining the Pacific Rim, including Canada.

    Pilarczyk points to low-lying areas like Delta, Richmond and Port Alberni as potentially vulnerable to tsunamis originating from this region.

    In 2011 eastern Japan was hit with a massive magnitude 9 quake – creating the largest rupture area of any earthquake originating from the Japan Trench. It triggered the Fukushima Daiichi nuclear disaster and a tsunami that travelled thousands of miles away—impacting the shores of British Columbia, California, Oregon, Hawaii and Chile.

    For the past decade, Pilarczyk and an international team of collaborators have been working with The Geological Survey of Japan, AIST|産総研 地質調査総合センタ](JP) to study Japan’s unique geologic history. Together, they uncovered and analyzed sandy deposits from the Boso Peninsula region (50 km east of Tokyo) that they attribute to an unusually large tsunami that occurred about 1,000 years ago.

    Until now, scientists did not have historical records to ascertain if a portion of the Philippine Sea/Pacific plate boundary near the Boso Peninsula was capable of generating large tsunamis similar in size as the Tohoku event in 2011.

    Using a combination of radiocarbon dating, geologic and historical records, and paleoecology, the team used 13 hypothetical and historical models to assess each of the three plate boundaries, including the Continental/Philippine Sea plate boundary (Sagami Trough), the Continental/Pacific plate boundary (Japan Trench) and the Philippine Sea/Pacific plate boundary (Izu-Bonin Trench) as sources of the 1,000-year-old earthquake.

    2
    Jessica Pilarczyk (SFU) and collaborator Tina Dura (The Virginia Polytechnic Institute and State University (US)) sample sediment cores from rice paddies of the Greater Tokyo Region that contain evidence for an earthquake from 1,000 years ago that potentially originated from a historically unconsidered earthquake source. Credit: SFU.

    Pilarczyk reports that the modeled scenarios suggest that the source of the tsunami from 1,000 years ago originated from the offshore area off the Boso Peninsula — the smallest of which (for example, possible earthquakes with the lowest minimum magnitude), are linked to the previously unconsidered Izu-Bonin Trench at the boundary of the Philippine Sea and Pacific plates.

    “Earthquake hazard assessments for the Tokyo region are complicated by the’ trench-trench triple junction’, where the oceanic Philippine Sea Plate not only underthrusts a continental plate but is also being subducted by the Pacific Plate.”says Pilarczyk, an assistant professor of Earth sciences at SFU who holds a Canada Research Chair in Natural Hazards. ”Great thrust earthquakes and associated tsunamis are historically recognized hazards from the Continental/Philippine Sea (Sagami Trough) and Continental/Pacific (Japan Trench) plate boundaries but not from the Philippine Sea/Pacific boundary alone.”

    Pilarczyk hopes that these findings will be used to produce better informed seismic hazard maps for Japan. She also says that this information could be used by far-field locations, including Canada, to inform building practices and emergency management strategies that would help mitigate the destructive consequences of an earthquake similar to the one of 1,000 years ago.

    See the full article here.

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    Simon Fraser University (CA) is a public research university in British Columbia, Canada, with three campuses: Burnaby (main campus), Surrey, and Vancouver. The 170-hectare (420-acre) main Burnaby campus on Burnaby Mountain, located 20 kilometres (12 mi) from downtown Vancouver, was established in 1965 and comprises more than 30,000 students and 160,000 alumni. The university was created in an effort to expand higher education across Canada.

    Simon Fraser University (CA) is a member of multiple national and international higher education, including the Association of Commonwealth Universities, International Association of Universities, and Universities Canada (CA). Simon Fraser University has also partnered with other universities and agencies to operate joint research facilities such as the TRIUMF- Canada’s particle accelerator centre [Centre canadien d’accélération des particules] (CA) for particle and nuclear physics, which houses the world’s largest cyclotron, and Bamfield Marine Station, a major centre for teaching and research in marine biology.

    Undergraduate and graduate programs at Simon Fraser University (CA) operate on a year-round, three-semester schedule. Consistently ranked as Canada’s top comprehensive university and named to the Times Higher Education list of 100 world universities under 50, Simon Fraser University (CA)is also the first Canadian member of the National Collegiate Athletic Association, the world’s largest college sports association. In 2015, Simon Fraser University (CA) became the second Canadian university to receive accreditation from the Northwest Commission on Colleges and Universities. Simon Fraser University (CA) faculty and alumni have won 43 fellowships to the Royal Society of Canada [Société royale du Canada](CA), three Rhodes Scholarships and one Pulitzer Prize. Among the list of alumni includes two former premiers of British Columbia, Gordon Campbell and Ujjal Dosanjh, owner of the Vancouver Canucks NHL team, Francesco Aquilini, Prime Minister of Lesotho, Pakalitha Mosisili, director at the Max Planck Society [Max Planck Gesellschaft](DE) , Robert Turner, and humanitarian and cancer research activist, Terry Fox.

     
  • richardmitnick 2:43 pm on August 23, 2021 Permalink | Reply
    Tags: "Earth’s Continents Share an Ancient Crustal Ancestor", , , , , Paleogeology   

    From Eos: “Earth’s Continents Share an Ancient Crustal Ancestor” 

    From AGU
    Eos news bloc

    From Eos

    8.23.21
    Julie Hollis
    juho@nanoq.gl
    Chris Kirkland
    Michael Hartnady
    Milo Barham
    Agnete Steenfelt

    1
    Researchers collect stream sediments in Greenland. Zircons from these sediments have provided tantalizing clues to how today’s continents came to be. Credit: Agnete Steenfelt.

    The jigsaw fit of Earth’s continents, which long intrigued map readers and inspired many theories, was explained about 60 years ago when the foundational processes of plate tectonics came to light. Topographic and magnetic maps of the ocean floor revealed that the crust—the thin, rigid top layer of the solid Earth—is split into plates. These plates were found to shift gradually around the surface atop a ductile upper mantle layer called the asthenosphere. Where dense oceanic crust abuts thicker, buoyant continents, the denser crust plunges back into the mantle beneath. Above these subduction zones, upwelling mantle melt generates volcanoes, spewing lava and creating new continental crust.

    From these revelations, geologists had a plausible theory for how the continents formed and perhaps how Earth’s earliest continents grew—above subduction zones. Unfortunately, the process is not that simple, and plate tectonics have not always functioned this way [Tectonophysics]. Subsequent research since the advent of plate tectonic theory has shown that subduction and associated mantle melting provide only a partial explanation for the formation and growth of today’s continents. To better understand the production and recycling of crust, some scientists, including our team, have shifted from studying the massive moving plates to detailing the makeup of tiny mineral crystals that have stood the test of time.

    Starting in the 1970s, geologists from the Greenland Geological Survey collected stream sediments from all over Greenland, sieving them to sand size and chemically analyzing them to map the continent-scale geochemistry and contribute to finding mineral occurrences. Unbeknownst to them at the time, tiny grains of the mineral zircon contained in the samples held clues about the evolution of Earth’s early crust. After decades in storage in a warehouse in Denmark, the zircon grains in those carefully archived bottles of sand—and the technology to analyze them—were ready to reveal their secrets.

    3
    This cathodoluminescence image shows the internal structure of magnified zircons analyzed by laser ablation. Credit: Chris Kirkland.

    Zircon occurs in many rock types in continental crust, and importantly, it is geologically durable. These tiny mineral time capsules preserve records of the distant past—as far back as 4.4 billion years—which are otherwise almost entirely erased. More than just recording the time at which a crystal grew, zircon chemistry records information about the magma from which it grew, including whether the magma originated from a melted piece of older crust, from the mantle, or from some combination of these sources. Through the isotopic signatures in a zircon grain, we can track its progression, from the movement of the magma up from the mantle, to its crystallization, to the grain’s uplift to the surface and its later erosion and redeposition.

    The Past Is Not Always Prologue

    New continental crust is formed above subduction zones, but it is also destroyed at subduction zones [e.g., Scholl and von Heune, 2007*]. Formation and destruction occur at approximately equal rates in a planetary-scale yin and yang [Stern and Scholl, 2010; Hawkesworth et al., 2019]. So crust formation above subduction zones cannot satisfactorily account for growth of the continents.

    *See References

    What’s more, plate tectonic movements like we see on Earth today did not operate the same way during Earth’s early history. Although there are indications that subduction may have occurred in Earth’s early history [Nature] (at least locally), many geochemical, isotopic, petrological, and thermal modeling studies of crust formation processes suggest that plate tectonics started gradually and didn’t begin operating as it does today until about 3 billion years ago, after more than a quarter of Earth’s history had already passed [e.g., McClennan and Taylor, 1983; Dhuime et al., 2015; Hartnady and Kirkland, 2019]. Because the mantle was much hotter at that time, more of it melted than it does now, producing large amounts of oceanic crust that was both too thick and too viscous to subduct.

    Nonetheless, although subduction was apparently not possible on a global scale before about 3 billion years ago, geochemical and isotopic evidence shows that a large volume of continental crust had already formed by that time [e.g., Hawkesworth et al., 2019; Condie, 2014; Taylor and McClennan 1995].

    If subduction didn’t generate the volume of continental crust we see today, what did?

    How Did Earth’s Early Crust Form?

    The nature of early Earth dynamics and how and when the earliest continental crust formed have remained topics of intense debate, largely because so little remains of Earth’s ancient crust for direct study. Various mechanisms have been proposed.

    Perhaps plumes of hot material rising from the mantle melted the oceanic crustal rock above [Smithies et al., 2005]. If dense portions of this melted rock “dripped” back into the mantle, they could have stirred convection cells in the upper mantle. These drips might have also added water to the mantle, lowering its melting point and producing new melts that ascended into the crust [Johnson et al., 2014].

    Or maybe meteorite impacts punched through the existing crust into the mantle, generating new melts that, again, ascended toward the surface and added new crust [Hansen, 2015]. Another possibility is that enough heat built up at the base of the thick oceanic crust on early Earth that parts of the crust remelted, with the less dense, buoyant melt portions then rising and forming pockets of continental crust [Smithies et al., 2003].

    By whichever processes Earth’s first continental crust formed, how did the large volume of continental crust we have now build up? Our research helps resolve this question [Kirkland et al., 2021].

    Answers Hidden in Greenland Zircons

    We followed the histories of zircon crystals through the eons by probing the isotopes preserved in grains from the archived stream sediment samples from an area of west Greenland. These isotopes were once dissolved within molten mantle before being injected into the crust by rising magmas that crystallized zircons and lifted them up to the surface. Eventually, wind and rain erosion released the tiny crystals from their rock hosts, and rivulets of water tumbled them down to quiet corners in sandy stream bends. There they rested until geologists gathered the sand, billions of years after the zircons formed inside Earth.

    In the laboratory, we extracted thousands of zircon grains from the sand samples. These grains—mounted inside epoxy resin and polished—were then imaged with a scanning electron microscope, revealing pictures of how each zircon grew, layer upon layer, so long ago.

    3
    Researchers used the laser ablation mass spectrometer at Curtin University (AU) to study isotopic ratios in zircon crystals. Credit: Chris Kirkland.

    In a mass spectrometer, the zircons were blasted with a laser beam, and a powerful magnetic field separated the resulting vapor into isotopes of different masses. We determined when each crystal formed using the measured amounts of radioactive parent uranium and daughter lead isotopes. We also compared the hafnium isotopic signature in each zircon with the signatures we would expect in the crust and in the mantle on the basis of the geochemical and isotopic fractionation of Earth through time. Using these methods, we determined the origins of the magma from which the crystals grew and thus built a history of the planet from grains of sand.

    Our analysis revealed that the zircon crystals varied widely in age, from 1.8 billion to 3.9 billion years old—a much broader range than what’s typically observed in Earth’s ancient crust. Because of both this broad age range and the high geographic density of the samples in our data set, patterns emerged in the data.

    In particular, some zircons of all ages had hafnium isotope signatures that showed that these grains originated from rocks that formed as a result of the melting of a common 4-billion-year-old parent continental crust. This common source implied that early continental crust did not form anew and discretely on repeated occasions. Instead, the oldest continental crust might have survived to serve as scaffolding for successive additions of younger continental crust.

    In addition to revealing this subtle, but ubiquitous, signature of Earth’s ancient crust in the Greenland samples, our data also showed something very significant about the evolution of Earth’s continental crust around 3 billion years ago. The hafnium signature of most of the zircons from that time that we analyzed showed a distinct isotopic signal linked to the input of mantle material into the magma from which these crystals grew. This strong mantle signal in the hafnium signature showed us that massive amounts of new continental crust formed in multiple episodes around this time by a process in which mantle magmas were injected into and melted older continental crust.

    4
    Geologists work atop a rock outcrop in the Maniitsoq region of western Greenland. Credit: Julie Hollis.

    The idea that ancient crust formed the scaffolding for later growth of continents was intriguing, but was it true? And was this massive crust-forming event related to some geological process restricted to what is now Greenland, or did this event have wider significance in Earth’s evolution?

    A Global Crust Formation Event

    To test our hypotheses, we looked at data sets of isotopes in zircons from other parts of the world where ancient continental crust is preserved. As with our Greenland data, these large data sets all showed evidence of repeated injection of mantle melts into much more ancient crust. Ancient crust seemed to be a prerequisite for growing new crust.

    Moreover, the data again showed that these large volumes of mantle melts were injected into older crust everywhere at about the same time, between 3.2 billion and 3.0 billion years ago, timing that coincides with the estimated peak in Earth’s mantle temperatures [Earth and Planetary Science Letters]. This “hot flash” in the deep Earth may have enabled huge volumes of melt to rise from the mantle and be injected into existing older crust, driving a planetary continent growth spurt.

    The picture that emerges from our work is one in which buoyant pieces of the oldest continental crust melted during the accrual and trapping of new mantle melts in a massive crust-forming event about 3 billion years ago. This global event effectively, and rapidly, built the continents. With the onset of the widespread subduction that we see today, these continents have since been destroyed, remade, and shifted around the surface like so many jigsaw pieces in perpetuity through the eons.

    References

    Condie, K. (2014), Growth of continental crust: A balance between preservation and recycling, Mineral. Mag., 78(3), 623–637, https://doi.org/10.1180/minmag.2014.078.3.11.

    Dhuime, B., A. Wuestefeld, and C. J. Hawkesworth (2015), Emergence of modern continental crust about 3 billion years ago, Nat. Geo­sci., 8, 552–555, https://doi.org/10.1038/ngeo2466.

    Hansen, V. L. (2015), Impact origin of Archean cratons, Lithosphere, 7, 563–578, https://doi.org/10.1130/L371.1.

    Hartnady, M. I. H., and C. L. Kirkland (2019), A gradual transition to plate tectonics on Earth between 3.2 and 2.7 billion years ago, Terra Nova, 31, 129–134, https://doi.org/10.1111/ter.12378.

    Hawkesworth, C. J., B. Dhuime, and P. A. Cawood (2019), Rates of generation and growth of the continental crust, Geosci. Front., 10(1), 165–173, https://doi.org/10.1016/j.gsf.2018.02.004.

    Johnson, T. E., et al. (2014), Delamination and recycling of Archaean crust caused by gravitational instabilities, Nat. Geosci., 7, 47–52, https://doi.org/10.1038/ngeo2019.

    Kirkland, C. L., et al. (2021), Widespread reworking of Hadean-to-Eoarchean continents during Earth’s thermal peak, Nat. Commun., 12, 331, https://doi.org/10.1038/s41467-020-20514-4.

    McLennan, S. M., and S. R. Taylor (1983), Continental freeboard, sedimentation rates and growth of continental crust, Nature, 306, 169–172, https://doi.org/10.1038/306169a0.

    Scholl, D. W., and R. von Huene (2007), Crustal recycling at modern subduction zones applied to the past—Issues of growth and preservation of continental basement crust, mantle geochemistry, and supercontinent reconstruction, in 4-D Framework of Continental Crust, edited by R. D. Hatcher et al., Mem. Geol. Soc. Am., 200, 9–32, https://doi.org/10.1130/2007.1200(02).

    Smithies, R. H., D. C. Champion, and K. F. Cassidy (2003), Formation of Earth’s early Archaean continental crust, Precambrian Res., 127(1–3), 89–101, https://doi.org/10.1016/S0301-9268(03)00182-7.

    Smithies, R. H., M. J. Van Kranendonk, and D. C. Champion (2005), It started with a plume — Early Archaean basaltic proto-continental crust, Earth Planet. Sci. Lett., 238, 284–297, https://doi.org/10.1016/j.epsl.2005.07.023.

    Stern, R. J., and D. W. Scholl (2010), Yin and yang of continental crust creation and destruction by plate tectonic processes, Int. Geol. Rev., 52(1), 1–31, https://doi.org/10.1080/00206810903332322.

    Taylor, S. R., and S. M. McLennan (1995), The geochemical evolution of the continental crust, Rev. Geophys., 33(2), 241–265, https://doi.org/10.1029/95RG00262.

    See the full article here .

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    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 10:33 am on August 22, 2021 Permalink | Reply
    Tags: "The Grand Canyon Is Missing a Billion Years' Worth of Rocks. Scientists May Know Why", , , , , Paleogeology, , Thermochronology: a series of chemical analysis techniques to measure the heat stored in rock when it was formed.,   

    From University of Colorado-Boulder (US) via Science Alert (US) : “The Grand Canyon Is Missing a Billion Years’ Worth of Rocks. Scientists May Know Why” 

    U Colorado

    From University of Colorado-Boulder (US)

    via

    ScienceAlert

    Science Alert (US)

    22 AUGUST 2021
    DAVID NIELD

    1
    Credit: Dean Fikar/Moment/Getty Images.

    Few geological mysteries are as perplexing as the “Great Unconformity” riddle at the Grand Canyon: More than a billion years of missing rock layers that for some reason weren’t deposited and stacked like the rest of the geological record. It’s as though those years never happened.

    This strange gap was first spotted by geologist John Wesley Powell in 1869, as he journeyed down the Colorado River. Later, we would be able to date those layers. In some places, rocks dated to 1.4-1.8 billion years ago sit next to rocks that are just 520 million years old.

    “There are beautiful lines,” says geologist Barra Peak from the University of Colorado-Boulder (US). “At the bottom, you can see very clearly that there are rocks that have been pushed together. Their layers are vertical. Then there’s a cutoff, and above that, you have these beautiful horizontal layers that form the buttes and peaks that you associate with the Grand Canyon.”

    Where did the rest of these rocks go?

    In a new study, scientists think they might have an explanation: They’re proposing that the geological history of the Grand Canyon is more complex than previously thought and that different parts of the site may have shifted in different ways across the millennia, causing some rock and sediment to get washed away to the ocean.

    “We have new analytical methods in our lab that allow us to decipher the history in the missing window of time across the Great Unconformity,” says geologist Rebecca Flowers, also from the University of Colorado Boulder.

    “We are doing this in the Grand Canyon and at other Great Unconformity localities across North America.”

    These new methods primarily rely on thermochronology, which uses a series of chemical analysis techniques to measure the heat stored in rock when it was formed. This heat corresponds to the amount of pressure that geological formations were under.

    The data collected by the researchers suggest there were a series of small but significant faulting events that account for the gaps in the geological record. These would have coincided with the violent breakup of the supercontinent Rodinia, roughly 633 to 750 million years ago, a tumultuous time in terms of Earth’s tectonics that may have meant rock layers didn’t settle in a more uniform way.

    According to samples collected and analyzed by the team, the western half of the Grand Canyon has gone through very different geologic contortions compared to the eastern half, which is the one tourists will be most familiar with.

    “It’s not a single block with the same temperature history,” says Peak.

    For example, basement rock in the western half of the canyon seems to have risen to the surface some 700 million years ago; in the eastern half, the same layers of stone are buried under several kilometers of sediment.

    The findings aren’t quite enough to close the mysterious case of the Great Unconformity once and for all, but they’re a good step forward – and the researchers think the same techniques can be applied at other sites in the US where similar kinds of geologic contortions have been observed.

    What is not in doubt is the way the Grand Canyon continues to inspire awe: not just in its natural beauty but also in the way it charts the geological history of our planet across billions of years.

    “There are just so many things there that aren’t present anywhere else,” says Peak. “It’s a really amazing natural lab.”

    The research has been published in Geology.

    See the full article here .

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    U Colorado Campus

    As the flagship university of the state of Colorado University of Colorado-Boulder (US), founded in 1876, five months before Colorado became a state. It is a dynamic community of scholars and learners situated on one of the most spectacular college campuses in the country, and is classified as an R1 University, meaning that it engages in a very high level of research activity. As one of 34 U.S. public institutions belonging to the prestigious Association of American Universities (US)), a selective group of major research universities in North America, – and the only member in the Rocky Mountain region – we have a proud tradition of academic excellence, with five Nobel laureates and more than 50 members of prestigious academic academies.

    University of Colorado-Boulder (US) has blossomed in size and quality since we opened our doors in 1877 – attracting superb faculty, staff, and students and building strong programs in the sciences, engineering, business, law, arts, humanities, education, music, and many other disciplines.

    Today, with our sights set on becoming the standard for the great comprehensive public research universities of the new century, we strive to serve the people of Colorado and to engage with the world through excellence in our teaching, research, creative work, and service.

    In 2015, the university comprised nine colleges and schools and offered over 150 academic programs and enrolled almost 17,000 students. Five Nobel Laureates, nine MacArthur Fellows, and 20 astronauts have been affiliated with CU Boulder as students; researchers; or faculty members in its history. In 2010, the university received nearly $454 million in sponsored research to fund programs like the Laboratory for Atmospheric and Space Physics and JILA. CU Boulder has been called a Public Ivy, a group of publicly funded universities considered as providing a quality of education comparable to those of the Ivy League.

    The Colorado Buffaloes compete in 17 varsity sports and are members of the NCAA Division I Pac-12 Conference. The Buffaloes have won 28 national championships: 20 in skiing, seven total in men’s and women’s cross country, and one in football. The university has produced a total of ten Olympic medalists. Approximately 900 students participate in 34 intercollegiate club sports annually as well.

    On March 14, 1876, the Colorado territorial legislature passed an amendment to the state constitution that provided money for the establishment of the University of Colorado in Boulder, the Colorado School of Mines(US) in Golden, and the Colorado State University (US) – College of Agricultural Sciences in Fort Collins.

    Two cities competed for the site of the University of Colorado: Boulder and Cañon City. The consolation prize for the losing city was to be home of the new Colorado State Prison. Cañon City was at a disadvantage as it was already the home of the Colorado Territorial Prison. (There are now six prisons in the Cañon City area.)

    The cornerstone of the building that became Old Main was laid on September 20, 1875. The doors of the university opened on September 5, 1877. At the time, there were few high schools in the state that could adequately prepare students for university work, so in addition to the University, a preparatory school was formed on campus. In the fall of 1877, the student body consisted of 15 students in the college proper and 50 students in the preparatory school. There were 38 men and 27 women, and their ages ranged from 12–23 years.

    During World War II, Colorado was one of 131 colleges and universities nationally that took part in the V-12 Navy College Training Program which offered students a path to a navy commission.

    University of Colorado-Boulder (US) hired its first female professor, Mary Rippon, in 1878. It hired its first African-American professor, Charles H. Nilon, in 1956, and its first African-American librarian, Mildred Nilon, in 1962. Its first African American female graduate, Lucile Berkeley Buchanan, received her degree in 1918.

    Research institutes

    University of Colorado-Boulder’s (US) research mission is supported by eleven research institutes within the university. Each research institute supports faculty from multiple academic departments, allowing institutes to conduct truly multidisciplinary research.

    The Institute for Behavioral Genetics (IBG) is a research institute within the Graduate School dedicated to conducting and facilitating research on the genetic and environmental bases of individual differences in behavior. After its founding in 1967 IBG led the resurging interest in genetic influences on behavior. IBG was the first post-World War II research institute dedicated to research in behavioral genetics. IBG remains one of the top research facilities for research in behavioral genetics, including human behavioral genetics, psychiatric genetics, quantitative genetics, statistical genetics, and animal behavioral genetics.

    The Institute of Cognitive Science (ICS) at CU Boulder promotes interdisciplinary research and training in cognitive science. ICS is highly interdisciplinary; its research focuses on education, language processing, emotion, and higher level cognition using experimental methods. It is home to a state of the art fMRI system used to collect neuroimaging data.

    ATLAS Institute is a center for interdisciplinary research and academic study, where engineering, computer science and robotics are blended with design-oriented topics. Part of CU Boulder’s College of Engineering and Applied Science, the institute offers academic programs at the undergraduate, master’s and doctoral levels, and administers research labs, hacker and makerspaces, and a black box experimental performance studio. At the beginning of the 2018–2019 academic year, approximately 1,200 students were enrolled in ATLAS academic programs and the institute sponsored six research labs.[64]

    In addition to IBG, ICS and ATLAS, the university’s other institutes include Biofrontiers Institute, Cooperative Institute for Research in Environmental Sciences, Institute of Arctic & Alpine Research (INSTAAR), Institute of Behavioral Science (IBS), JILA, Laboratory for Atmospheric & Space Physics (LASP), Renewable & Sustainable Energy Institute (RASEI), and the University of Colorado Museum of Natural History.

     
  • richardmitnick 2:41 pm on August 20, 2021 Permalink | Reply
    Tags: "Swipe Left on the 'Big One' Better Dates for Cascadia Quakes", , , Coseismic coastal deformation, , , , Geochronometers, Geologic proxies of megathrust earthquakes are generated by different aspects of the rupture process and can therefore inform us about specific rupture characteristics and hazards., , Ghost forests, New data collections from coastal forests that perished in or survived through CSZ earthquakes can now give near-annual dates for both inundations and ecosystem transitions., Paleogeology, , The last behemoth earthquake on the CSZ estimated at magnitude 9 struck on 26 January 1700.   

    From Eos: “Swipe Left on the ‘Big One’- Better Dates for Cascadia Quakes” 

    From AGU
    Eos news bloc

    From Eos

    8.20.21
    Jessie K. Pearl
    Lydia Staisch
    lstaisch@usgs.gov

    1
    The dead trees in this ghost forest in Copalis, Wash., were killed during the last major Cascadia earthquake in January 1700. Credit: Jessie K. Pearl. [Ed.: If it was 1700 C.E., how are they still standing?]

    The CSZ is a tectonic boundary off the coast that has unleashed massive earthquakes and tsunamis as the Juan de Fuca Plate is thrust beneath the North American Plate. And it will do so again. But when? And how big will the earthquake—or earthquakes—be?

    The last behemoth earthquake on the CSZ estimated at magnitude 9 struck on 26 January 1700. We know this age with such precision—unique in paleoseismology—because of several lines of geologic proxy evidence that coalesce around that date, in addition to Japanese historical records describing an “orphan tsunami” (a tsunami with no corresponding local earthquake) on that particular date [Atwater et al., 2015*]. Indigenous North American oral histories also describe the event. Geoscientists have robust evidence for other large earthquakes in Cascadia’s past; however, deciphering and precisely dating the geologic record become more difficult the farther back in time you go.

    *All cited works in References below.

    Precision dating of and magnitude constraints on past earthquakes are critically important for assessing modern CSZ earthquake hazards. Such estimates require knowledge of the area over which the fault has broken in the past; the amount of displacement, or slip, on the fault; the speed at which slip occurred; and the timing of events and their potential to occur in rapid succession (called clustering). The paucity of recent seismicity on the CSZ means our understanding of earthquake recurrence there primarily comes from geologic earthquake proxies, including evidence of coseismic land level changes, tsunami inundations, and strong shaking found in onshore and marine environments (Figure 1). Barring modern earthquakes, increasing the accuracy and precision of paleoseismological records is the only way to better constrain the size and frequency of megathrust ruptures and to improve our understanding of natural variability in CSZ earthquake hazards.

    1
    Fig. 1. Age ranges obtained from different geochronologic methods used for estimating Cascadia Subduction Zone megathrust events are shown in this diagram of preservation environments. At top is a dendrochronological analysis comparing a tree killed from a megathrust event with a living specimen. Here ^14C refers to radiocarbon (or carbon-14), and “wiggle-match ^14C” refers to an age model based on multiple, relatively dated (exact number of years known between samples) annual tree ring samples. Schematic sedimentary core observations and sample locations are shown for marsh and deep-sea marine environments. Gray probability distributions for examples of each 14C method are shown to the right of the schematic cores, with 95% confidence ranges in brackets. Optically stimulated luminescence (OSL)-based estimates are shown as a gray dot with error bars.

    To discuss ideas, frontiers, and the latest research at the intersection of subduction zone science and geochronology, a variety of specialists attended a virtual workshop about earthquake recurrence on the CSZ hosted by the Geological Survey (US) in February 2021. The workshop, which we discuss below, was part of a series that USGS is holding as the agency works on the next update of the National Seismic Hazard Model, due out in 2023.

    Paleoseismology Proxies

    Cascadia has one of the longest and most spatially complete geologic records of subduction zone earthquakes, stretching back more than 10,000 years along much of the 1,300-kilometer-long margin, yet debate persists over the size and recurrence of great earthquakes [Goldfinger et al., 2012; Atwater et al., 2014]. The uncertainty arises in part because we lack firsthand observations of Cascadia earthquakes. Thus, integrating onshore and offshore proxy records and understanding how different geologic environments record past megathrust ruptures remain important lines of inquiry, as well as major hurdles, in CSZ science. These hurdles are exacerbated by geochronologic data sets that differ in their precision and usefulness in revealing past rupture patches.

    One of the most important things to determine is whether proxy evidence records the CSZ rupturing in individual great events (approximately magnitude 9) or in several smaller, clustered earthquakes (approximately magnitude 8) that occur in succession. A magnitude 9 earthquake releases 30 times the energy of a magnitude 8 event, so the consequences of misinterpreting the available data can result in substantial misunderstanding of the seismic hazard.

    Geologic proxies of megathrust earthquakes are generated by different aspects of the rupture process and can therefore inform us about specific rupture characteristics and hazards. Some of the best proxy records for CSZ earthquakes lie onshore in coastal environments. Coastal wetlands, for example, record sudden and lasting land-level changes in their stratigraphy and paleoecology when earthquakes cause the wetlands’ surfaces to drop into the tidal range (Figure 1) [Atwater et al., 2015]. The amount of elevation change that occurs during a quake, called “coseismic deformation,” can vary along the coast during a single event because of changes in the magnitude, extent, and style of slip along the fault [e.g., Wirth and Frankel, 2019]. Thus, such records can reveal consistency or heterogeneity in slip during past earthquakes.

    Tsunami deposits onshore are also important proxies for understanding coseismic slip distribution. Tsunamis are generated by sudden seafloor deformation and are typically indicative of shallow slip, near the subduction zone trench (Figure 1) [Melgar et al., 2016]. The inland extent of tsunami deposits, and their distribution north and south along the subduction zone, can be used to identify places where an earthquake caused a lot of seafloor deformation and can tell generally how much displacement was required to create the tsunami wave.

    Offshore, seafloor sediment cores show coarse layers of debris flows called turbidites that can also serve as great proxies for earthquake timing and ground motion characteristics. Coseismic turbidites result when earthquake shaking causes unstable, steep, submarine canyon walls to fail, creating coarse, turbulent sediment flows. These flows eventually settle on the ocean floor and are dated using radiocarbon measurements of detrital organic-rich material.

    Geochronologic Investigations

    3
    Fig. 2. These graphs show the age range over which different geochronometers are useful (top), the average record length in Cascadia for different environments (middle), and the average uncertainty for different methods (bottom). Marine sediment cores have the capacity for the longest records, but age controls from detrital material in turbidites have the largest age uncertainties. Radiocarbon (^14C) ages from bracketing in-growth position plants and trees (wiggle matching) have much smaller uncertainties (tens of years) but are not preserved in coastal environments for as long. To optimize the potential range of dendrochronological geochronometers, the reference chronology of coastal tree species must be extended further back in time. The range limit (black arrow) of these geochronometers could thus be extended with improved reference chronologies.

    To be useful, proxies must be datable. Scientists primarily use radiocarbon dating to put past earthquakes into temporal context. Correlations in onshore and offshore data sets have been used to infer the occurrence of up to 20 approximately magnitude 9 earthquakes on the CSZ over the past 11,000 years [Goldfinger et al., 2012], although uncertainty in the ages of these events ranges from tens to hundreds of years (Figure 2). These large age uncertainties allow for varying interpretations of the geologic record: Multiple magnitude 8 or magnitude 7 earthquakes that occur over a short period of time (years to decades) could be misidentified as a single huge earthquake. It’s even possible that the most thoroughly examined CSZ earthquake, in 1700, might have comprised a series of smaller earthquakes, not one magnitude 9 event, because the geologic evidence providing precise ages of this event comes from a relatively short stretch of the Cascadia margin [Melgar, 2021].

    By far, the best geochronologic age constraints for CSZ earthquakes come from tree ring, or dendrochronological, analyses of well-preserved wood samples [e.g., Yamaguchi et al., 1997], which can provide annual and even seasonal precision (Figure 2). Part of how scientists arrived at the 26 January date for the 1700 quake was by using dendrochronological dating of coastal forests in southwestern Washington that were killed rapidly by coseismic saltwater submergence. Some of the dead western red cedar trees in these “ghost forests” are preserved with their bark intact; thus, they record the last year of their growth. By cross dating the dead trees’ annual growth rings with those in a multicentennial reference chronology derived from nearby living trees, it is evident that the trees died after the 1699 growing season.

    The ghost forest, however, confirms only that coseismic submergence in 1700 occurred along the 90 kilometers of the roughly 1,300-kilometer-long Cascadia margin where these western red cedars are found. The trees alone do not confirm that the entire CSZ fault ruptured in a single big one.

    Meanwhile, older CSZ events have not been dated with such high accuracy, in part because coseismically killed trees are not ubiquitously distributed and well preserved along the coastline and because there are no millennial-length, species-specific reference chronologies with which to cross date older preserved trees (Figure 2).

    Advances in Dating

    At the Cascadia Recurrence Workshop earlier this year, researchers presented recent advances and discussed future directions in paleoseismic dating methods. For example, by taking annual radiocarbon measurements from trees killed during coseismic coastal deformation, we can detect dated global atmospheric radiocarbon excursions in these trees, such as the substantial jump in atmospheric radiocarbon between the years 774 and 775 [Miyake et al., 2012]. This method allows us to correlate precise dates from other ghost forests along the Cascadian coast from the time of the 1700 event and to date past megathrust earthquakes older than the 1700 quake without needing millennial-scale reference chronologies [e.g., Pearl et al., 2020]. Such reference chronologies, which were previously required for annual age precision, are time- and labor-intensive to develop. With this method, new data collections from coastal forests that perished in or survived through CSZ earthquakes can now give near-annual dates for both inundations and ecosystem transitions.

    4
    Numerous tree rings are evident in this cross section from a subfossil western red cedar from coastal Washington. Patterns in ring widths give clues about when the tree died. Credit: Jessie K. Pearl.

    Although there are many opportunities to pursue with dendrochronology, such as dating trees at previously unstudied sites and trees killed by older events, we must supplement this approach with other novel geochronological methods to fill critical data gaps where trees are not preserved. Careful sampling and interpretation of age results from radiocarbon-dated material other than trees can also provide tight age constraints for tsunami and coastal submergence events.

    For example, researchers collected soil horizons below (predating) and overlying (postdating) a tsunami deposit in Discovery Bay, Wash., and then radiocarbon dated leaf bases of Triglochin maritima, a type of arrowgrass that grows in brackish and freshwater marsh environments. The tsunami deposits, bracketed by well-dated pretsunami and posttsunami soil horizons, revealed a tsunamigenic CSZ rupture that occurred about 600 years ago on the northern CSZ, perhaps offshore Washington State and Vancouver Island [Garrison-Laney and Miller, 2017].

    Multiple bracketing ages can dramatically reduce uncertainty that plagues most other dated horizons, especially those whose ages are based on single dates from detrital organic material (Figure 2). Although the age uncertainty of the 600-year-old earthquake from horizons at Discovery Bay is still on the order of several decades, the improved precision is enough to conclusively distinguish the event from other earthquakes dated along the margin.

    Further advancements in radiocarbon dating continue to provide important updates for dating coseismic evidence from offshore records. Marine turbidites do not often contain materials that provide accurate age estimates, but they are a critically important paleoseismic proxy [Howarth et al., 2021]. Turbidite radiocarbon ages rely on correcting for both global and local marine reservoir ages, which are caused by the radiocarbon “memory” of seawater. Global marine reservoir age corrections are systematically updated by experts as we learn more about past climates and their influences on the global marine radiocarbon reservoir [Heaton et al., 2020]. However, samples used to calibrate the local marine reservoir corrections in the Pacific Northwest, which apply only to nearby sites, are unfortunately not well distributed along the CSZ coastline, and little is known about temporal variations in the local correction, leading to larger uncertainty in event ages.

    These local corrections could be improved by collecting more sampled material that fills spatial gaps and goes back further in time. At the workshop, researchers presented the exciting development that they were in the process of collecting annual radiocarbon measurements from Pacific geoduck clam shells off the Cascadian coastline to improve local marine reservoir knowledge. Geoducks can live more than 100 years and have annual growth rings that are sensitive to local climate and can therefore be cross dated to the exact year. Thus, a chronology of local climatic variation and marine radiocarbon abundance can be constructed using living and deceased specimens. Annual measurements of radiocarbon derived from marine bivalves, like the geoduck, offer new avenues to generate local marine reservoir corrections and improve age estimates for coseismic turbidity flows.

    Putting It All Together

    An imminent magnitude 9 megathrust earthquake on the CSZ poses one of the greatest natural hazards in North America and motivates diverse research across the Earth sciences. Continued development of multiple geochronologic approaches will help us to better constrain the timing of past CSZ earthquakes. And integrating earthquake age estimates with the understanding of rupture characteristics inferred from geologic evidence will help us to identify natural variability in past earthquakes and a range of possible future earthquake hazard scenarios.

    Useful geochronologic approaches include using optically stimulated luminescence to date tsunami sand deposits (Figure 1) and determining landslide age estimates on the basis of remotely sensed land roughness [e.g., LaHusen et al., 2020]. Of particular value will be focuses on improving high-precision radiocarbon and dendrochronological dating of CSZ earthquakes, paired with precise estimates of subsidence magnitude, tsunami inundation from hydrologic modeling, inferred ground motion characteristics from sedimentological variations in turbidity deposits, and evidence of ground failure in subaerial, lake, and marine settings. Together, such lines of evidence will lead to better correlation of geologic records with specific earthquake rupture characteristics.

    Ultimately, characterizing the recurrence of major earthquakes on the CSZ megathrust—which have the potential to drastically affect millions of lives across the region—hinges on the advancement and the integration of diverse geochronologic and geologic records.

    References:

    Atwater, B. F., et al. (2014), Rethinking turbidite paleoseismology along the Cascadia subduction zone, Geology, 42(9), 827–830, https://doi.org/10.1130/G35902.1.

    Atwater, B. F., et al. (2015), The Orphan Tsunami, 2nd ed., U.S. Geol. Surv., Reston, Va.

    Garrison-Laney, C., and I. Miller (2017), Tsunamis in the Salish Sea: Recurrence, sources, hazards, in From the Puget Lowland to East of the Cascade Range: Geologic Excursions in the Pacific Northwest, GSA Field Guide, vol. 49, pp. 67–78, Geol. Soc. of Am., Boulder, Colo. https://doi.org/10.1130/2017.0049(04).

    Goldfinger, C., et al. (2012), Turbidite event history — Methods and implications for Holocene paleoseismicity of the Cascadia Subduction Zone, U.S. Geol. Surv. Prof. Pap., 1661-F, https://doi.org/10.3133/pp1661F.

    Heaton, T. J., et al. (2020), Marine20—The marine radiocarbon age calibration curve (0–55,000 cal BP), Radiocarbon, 62(4), 779–820, https://doi.org/10.1017/RDC.2020.68.

    Howarth, J. D., et al. (2021), Calibrating the marine turbidite palaeoseismometer using the 2016 Kaikōura earthquake, Nat. Geosci., 14(3), 161–167, https://doi.org/10.1038/s41561-021-00692-6.

    LaHusen, S. R., et al. (2020), Rainfall triggers more deep-seated landslides than Cascadia earthquakes in the Oregon Coast Range, USA, Sci. Adv., 6(38), eaba6790, https://doi.org/10.1126/sciadv.aba6790.

    Melgar, D. (2021), Was the January 26th, 1700 Cascadia earthquake part of an event sequence?, EarthArXiv, https://doi.org/10.31223/X5XG78.

    Melgar, D., et al. (2016), Kinematic rupture scenarios and synthetic displacement data: An example application to the Cascadia subduction zone, J. Geophys. Res. Solid Earth, 121, 6,658–6,674, https://doi.org/10.1002/2016JB013314.

    Miyake, F., et al. (2012), A signature of cosmic-ray increase in AD 774–775 from tree rings in Japan, Nature, 486(7402), 240–242, https://doi.org/10.1038/nature11123.

    Pearl, J. K., et al. (2020), A late Holocene subfossil Atlantic white cedar tree-ring chronology from the northeastern United States, Quat. Sci. Rev., 228, 106104, https://doi.org/10.1016/j.quascirev.2019.106104.

    Wirth, E. A., and A. D. Frankel (2019), Impact of down-dip rupture limit and high-stress drop subevents on coseismic land-level change during Cascadia Megathrust earthquakes, Bull. Seismol. Soc. Am., 109(6), 2,187–2,197, https://doi.org/10.1785/0120190043.

    Yamaguchi, D. K., et al. (1997), Tree-ring dating the 1700 Cascadia earthquake, Nature, 389(6654), 922–923, https://doi.org/10.1038/40048.

    See the full article here .

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  • richardmitnick 12:56 pm on August 13, 2021 Permalink | Reply
    Tags: "Don’t Call It a Supervolcano", , , , , , Paleogeology, The movement of the North American tectonic plate over the Yellowstone hot spot has created a trail of volcanic activity across southern Idaho into Wyoming over the past 16.5 million years.,   

    From Eos: “Don’t Call It a Supervolcano” Photo Essay 

    From AGU
    Eos news bloc

    From Eos: : “Don’t Call It a Supervolcano” Photo Essay

    6 August 2021
    Mary Caperton Morton

    1
    The Black Canyon of the Yellowstone is considered the best early backpacking trip in the park. Credit: Mary Caperton Morton.

    “Yellowstone National Park, the world’s first and arguably most famous national park, is home to one of the planet’s largest and potentially most destructive volcanoes. The 50- by 70-kilometer Yellowstone caldera complex is so massive that it can really be appreciated only from the air.

    The magma chamber below Yellowstone is more than twice the size thought. Image: GETTY/WIKI).

    But although the caldera isn’t always visible on the ground, it’s certainly no secret: Copious thermal features like hot springs and geyser basins dot the landscape and have attracted people to the uniquely beautiful and ecologically rich area for at least 11,000 years.

    As people seek to explain the area’s geology, Yellowstone’s unusually active landscape has inspired myths and legends, from Indigenous origin stories to misleading headlines about the future. Every season, recurring bouts of earthquake swarms trigger sensational stories that Yellowstone could be gearing up for another “big one.” But there’s no need to cancel your family vacation to see the park’s free-roaming bison and grizzly bears: The geologists who keep a very close eye on the Yellowstone caldera system say it’s not going to erupt again in our lifetimes.

    Becoming Yellowstone

    The story of Yellowstone begins around 16.5 million years ago, when a plume of magma began fueling intense bouts of volcanism along the border of what is now Idaho, Nevada, and Oregon. This magma plume, like the one that formed the Hawaiian Islands, is stationary, but as the North American plate moves to the southwest over the hot spot, its surface expression migrates, creating a 750-kilometer-long trail of volcanism, including dozens of calderas, across southern Idaho and into northwest Wyoming.

    2
    The movement of the North American tectonic plate over the Yellowstone hot spot has created a trail of volcanic activity across southern Idaho into Wyoming over the past 16.5 million years. Credit: Geological Survey (US).

    Around 2.1 million years ago, when the hot spot was centered under the southwest corner of what is now Yellowstone National Park, the volcano’s magma reservoirs filled to bursting, resulting in one of the largest volcanic eruptions in the geologic record. The explosion spewed ash and debris all the way to the Mississippi River, ejecting more than 6,000 times the volume of material erupted during the 1980 Mount St. Helens eruption. As the magma chambers emptied, the overlying layers collapsed, forming a massive caldera.

    This cycle of explosive eruptions repeated twice more, around 1.3 million and 630,000 years ago, resulting in three overlapping calderas. In between these events, slow-moving lava flows drastically altered the landscape but didn’t affect the region beyond the immediate area. The last of these lava flows, which formed the Pitchstone Plateau in the southwest corner of the park, erupted around 70,000 years ago, and the volcano has been relatively quiet ever since.

    Nobody was around to witness Yellowstone’s last lava flow; humans were not yet living in North America 70,000 years ago. But people have been living in the area for at least 11,000 years, and thousands of artifacts and campsites have been found throughout the park, often concentrated around rivers, lakes, and obsidian sources.

    3
    Hot springs dot the shores of Yellowstone Lake, the largest lake in the park. Credit: Mary Caperton Morton.

    Prime campsites on the shores of Yellowstone Lake were continuously occupied for 9,500 years, and obsidian mined from dozens of quarries around the park has been found as far away as Wisconsin, Michigan, and Ontario. “Yellowstone was a nexus for trade and culture and is crossed by ancient trails from every direction,” said Shane Doyle, a research scientist at Montana State University (US) in Bozeman and a member of the Apsaalooke (Crow) Nation.

    When Yellowstone became the world’s first national park on 1 March 1872, Indigenous Peoples, including Bannock, Blackfeet, Crow, Flathead, Sheepeater, Shoshone, and Nez Perce, were still living in and migrating through the area. Tourism campaigns, however, touted Yellowstone as a pristine wilderness untouched by humanity. “The earliest intentions were to make people think that there were no Native Americans in the park and that they were never there,” Doyle said.

    One of the myths perpetuated by the park’s second superintendent is that Native Peoples were afraid of the area’s thermal features and avoided the area. But in fact, the hot springs and geysers were revered and used in ceremonies and vision quests, as well as daily life for processing food and trade goods, Doyle said. “Native people believe that Yellowstone is a very powerful and sacred place. They weren’t afraid of it. They had great respect for it, and geology plays an important role in many tribal legends and origin stories.”

    Such stories are only recently being shared with park visitors, Doyle said. “We’ve finally seen a breakthrough in the last year in efforts to educate visitors about Native history and culture. I look forward to seeing more signage and a more prominent Native presence throughout the park.”

    The Supervolcano Myth

    Yellowstone has an impressive volcanic resume—but don’t call it a supervolcano, a colloquial term with no scientific definition. Instead, geoscientists prefer the term Yellowstone caldera system or Yellowstone caldera complex. “I wish the word supervolcano could be banished from the record as it enforces the myth that Yellowstone only produces supereruptions,” said Michael Poland, the current scientist-in-charge of the Yellowstone Volcano Observatory (US) (USGS)3, the research consortium that monitors the volcano.

    In its 2.2-million-year history, the Yellowstone caldera system has erupted catastrophically only three times, while producing many localized lava flows. “Yellowstone is not going to erupt again anytime soon, and when it does, it’s much more likely to be a lava flow than an explosive event,” Poland said. “These lava flows are really impressive. They can be hundreds of feet thick. But they’re not particularly hazardous beyond the immediate area.”

    The last supereruption (defined as an event greater than magnitude 8 on the volcano explosivity index) at Yellowstone took place 630,000 years ago. The last lava flow took place 70,000 years ago. But the relative quiescence since the last eruptions doesn’t mean the system is due for an eruption, Poland said.

    “The most common misconception about Yellowstone is that it’s overdue for an eruption. But volcanoes don’t work like that,” he said. “They erupt when there is a sufficient supply of eruptable magma in the subsurface and enough pressure to get that magma to the surface, and right now, neither condition exists at Yellowstone.”

    Currently, the two stacked magma chambers under Yellowstone are mostly stagnant. “People tend to picture a giant pool of molten magma down there just waiting to erupt, but that’s not the case,” said Jamie Farrell, a seismologist at the University of Utah (US) who runs the seismic monitoring program at Yellowstone.

    Seismic studies that image the interior of Earth indicate that the two magma reservoirs contain between only 5% and 15% molten material. “That tells us the volcanic system is nowhere near primed for an eruption,” Farrell said. “Typically, you need at least 50% melt for it to mobilize and begin moving toward the surface.”

    The process of filling a magma chamber with molten material is not a quiet one. “We would expect to see increased seismicity, ground deformation, changes in thermal and gas emissions for decades and perhaps centuries in advance of an eruption,” Poland said. “We have a lot of confidence that if Yellowstone were gearing up for an eruptive event, we would know about it years in advance. It’s not going to take us by surprise.”

    Next-Level Neighborhood Watch

    Very little of what happens at Yellowstone above or below the ground goes unnoticed; the Yellowstone caldera is one of the best-monitored volcanoes on Earth. Satellites keep an eye on the seasonal cycles of ground deformation, while thermal and gas monitoring networks detect subtle changes in heat and gas outputs.

    4
    A map of the overlapping calderas, lava flows, and potential hazards of Yellowstone, including earthquakes and hydrothermal explosion craters. Credit: USGS.

    Dozens of permanent and hundreds of portable seismic stations spread throughout the park and around its borders keep tabs on Yellowstone’s near-constant quivering, including earthquake swarms, where hundreds of small earthquakes can occur over a period of days to months. These events often inspire sensational headlines that Yellowstone is awakening—but they are not harbingers of catastrophe, Farrell said, as they are usually triggered by water moving underground in the geothermal areas.

    The most likely hazards to strike the park on human timescales are not magma related, Farrell said. “The most likely geologic hazard would probably be a hydrothermal explosion.” As mineral-rich groundwater moves through hot springs and geysers, deposits thicken on the walls of the underground passages. Clogs can cause pressure to build up until an explosion occurs, sometimes forming a crater at the surface. “Some of these explosions can be pretty large. They happen annually, mostly in the backcountry, but they have happened in the major geyser basins before.”

    Explosions can also occur when groundwater rapidly flashes into steam. “In Yellowstone, there are a dozen or so decent-sized craters, a few hundreds of meters across, from hydrothermal explosion events,” Poland said “If that were to happen today in the front country, it could cause a lot of damage.”

    5
    The magnitude 7.3 Madison River Canyon earthquake kicked off a massive landslide that dammed the Madison River in 1959. Credit: Mary Caperton Morton.

    The next most likely hazard to affect park visitors is a large earthquake, Poland said. On 17 August 1959, a magnitude 7.3 earthquake struck the Yellowstone area and kicked off a 73-million-metric-ton landslide that dammed the Madison River. The landslide and resulting flooding killed 28 people, most of whom were camping along the river, and drastically changed the landscape by creating a new lake, Quake Lake.

    Today, another “strong earthquake could do a lot of damage to the park and impact visitors, but it’s not going to set off the volcano,” Poland said. “The system doesn’t work like that.”

    6
    Yellowstone’s hydrothermal systems, including the Old Faithful geyser, are among the most dynamic geologic elements in the park. Credit: Mary Caperton Morton.

    However, a big earthquake could affect the hydrothermal systems and perhaps increase or decrease geyser activity, Farrell said. “The thermal areas are very dynamic. There are a lot of old, inactive hydrothermal areas in the park, and we’ve seen new ones form in the past few decades. Old Faithful could shut down tomorrow, which would be a big change to the Yellowstone experience.”

    Farrell and his team are hoping to learn more about what factors drive changes to the park’s thermal features by deploying hundreds of battery-powered seismic instruments throughout the geyser basins. “We are hoping to develop hydrothermal monitoring systems, where we use seismometers, GPS stations, thermal and gas monitoring instruments to track changes on short timescales,” he said. The monitoring systems, which are on the YVO’s 10-year plan, may also provide some way of forewarning of impending hydrothermal explosions. “That’s a hazard we still don’t know much about,” Poland said.

    What’s Scarier Than Lions and Bisons and Bears? Climate Change, Oh My!

    7
    The author waits for a herd of bison to pass on the Hellroaring Creek segment of the Black Canyon of the Yellowstone hike. Credit: Mary Caperton Morton.

    In April, I backpacked through the Black Canyon of the Yellowstone, a 32-kilometer trek known for being the best early-season backpacking trip in the park. In the 3 days we spent on trail, we saw only two day hikers, dodged hundreds of bison and elk, and followed in the frighteningly fresh footsteps of both grizzly bears and mountain lions.

    When hiking in bear country, I travel in groups, make noise (I skip the bells and use my voice), carry bear spray, and store all food and scented items away from camp. In hundreds of kilometers of hiking in the Greater Yellowstone Ecosystem, I’ve seen a few bears in distant, peaceful encounters, and I’m sure many more have seen or heard me coming and stepped off the trail to let me pass. Bears have a huge task in feeding themselves with a mostly plant based diet, and I firmly believe that humans are not on their menu—they don’t want to encounter us any more than we want to encounter them.

    Keeping a clean camp and storing food properly high in a tree, up a bear pole, or in an approved bear canister are the best ways to keep bears from associating humans with food rewards. A famous park service saying is “a fed bear is a dead bear”: Sloppy people are far more dangerous to bears than bears are to people. Hiking, camping, and doing fieldwork in grizzly bear country can be stressful, agrees Madison Myers, a volcanologist at MSU in Bozeman, but with proper precautions, “I am honored to share space with them.”

    Yellowstone is famous for its long, deep winters, and a few decades ago, I might have needed snowshoes to hike the Black Canyon in early April and may have also been less likely to cross paths with still-hibernating bears. But the spring thaw is coming weeks earlier to Yellowstone, affecting snowpack, streamflow, water availability, vegetation patterns, and bear sleep schedules and stoking landscape-scale wildfires.

    In June, a team led by researchers at MSU released a new Greater Yellowstone Climate Assessment that found that average temperatures are the warmest they’ve been in the past 800,000 years, and carbon dioxide levels are the highest they’ve been in the past 3.3 million years. Since 1950, average temperatures have increased by 1.3℃, and the report predicts that without drastic measures to reduce carbon dioxide emissions, temperatures could soar by as much as 5.6℃ by the end of the 21st century.

    Grizzly tracks are formidable, but the human footprint on Yellowstone is large and getting larger.

    7
    Bison frequently roam on Yellowstone’s roads, often causing traffic jams. Credit: Mary Caperton Morton.

    In 2019, more than 4.2 million people visited the park, with visitation expected to soar even higher in 2021. Often portrayed as a vast wilderness, in reality the nearly 9,000-square-kilometer park is crisscrossed by more than 750 kilometers of roads that connect more than 1,500 buildings, including nine hotels and 11 visitor centers and museums.

    “On human timescales, I don’t think people will see that much large-scale geologic change in Yellowstone,” said Carol Stein, a geophysicist at the University of Illinois at Chicago. “Yellowstone is a lovely place and will stay lovely for a long time, but climate change is happening before our eyes and quickly altering the landscape. In our lifetimes, I expect climate will be the dominating force of change in Yellowstone.”

    Yellowstone, Forever

    Ask the average person to imagine the future of Yellowstone, and that person might picture a mushroom cloud looming over a smoking crater. “When people hear I study Yellowstone, they always ask, ‘When is it going to erupt?’ and when I tell them that the chance of an eruption in their lifetime is next to nothing, they’re almost disappointed,” Myers said. On longer timescales, “there is a chance of another eruption on million-year timescales, or it may never erupt again at all.”

    On multimillion-year timescales, as the North American plate continues moving southwest over the Yellowstone hot spot, the plume will migrate to the northeast, toward the thicker crust of the Beartooth Plateau. “When the plume hits the Beartooth Mountains, we don’t know what will happen,” Myers said. “Can volcanism work its way up through the plateau? Or will it somehow flow around the sides? Or will it wait until it pops out the other side near Billings in another 5 million years or so?”

    Could another Yellowstone arise in Montana’s largest city in a few million years? Will Billings even be on the map by then? Only geologic time will tell.

    See the full article here .

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    Please help promote STEM in your local schools.

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  • richardmitnick 9:24 pm on July 31, 2021 Permalink | Reply
    Tags: "Geologists take Earth’s inner temperature using erupted sea glass", , , Geologists at MIT have analyzed thousands of samples of erupted material along ocean ridges and traced back their chemical history to estimate the temperature of the Earth’s interior., , , , Paleogeology, ,   

    From Massachusetts Institute of Technology (US) : “Geologists take Earth’s inner temperature using erupted sea glass” 

    MIT News

    From Massachusetts Institute of Technology (US)

    July 29, 2021
    Jennifer Chu

    1
    A map of the World Ocean Floor
    Credits: Library of Congress, Geography and Map Division.

    If the Earth’s oceans were drained completely, they would reveal a massive chain of undersea volcanoes snaking around the planet. This sprawling ocean ridge system is a product of overturning material in the Earth’s interior, where boiling temperatures can melt and loft rocks up through the crust, splitting the sea floor and reshaping the planet’s surface over hundreds of millions of years.

    Now geologists at MIT have analyzed thousands of samples of erupted material along ocean ridges and traced back their chemical history to estimate the temperature of the Earth’s interior.

    Their analysis shows that the temperature of the Earth’s underlying ocean ridges is relatively consistent, at around 1,350 degrees Celsius — about as hot as a gas range’s blue flame. There are, however, “hotspots” along the ridge that can reach 1,600 degrees Celsius, comparable to the hottest lava.

    The team’s results, appearing in the Journal of Geophysical Research:Solid Earth, provide a temperature map of the Earth’s interior around ocean ridges. With this map, scientists can better understand the melting processes that give rise to undersea volcanoes, and how these processes may drive the pace of plate tectonics over time.

    “Convection and plate tectonics have been important processes in shaping Earth history,” says lead author Stephanie Brown Krein, a postdoc in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS). “Knowing the temperature along this whole chain is fundamental to understanding the planet as a heat engine, and how Earth might be different from other planets and able to sustain life.”

    Krein’s co-authors include Zachary Molitor, an EAPS graduate student, and Timothy Grove, the R.R. Schrock Professor of Geology at MIT.

    A chemical history

    The Earth’s interior temperature has played a critical role in shaping the planet’s surface over hundreds of millions of years. But there’s been no way to directly read this temperature tens to hundreds of kilometers below the surface. Scientists have applied indirect means to infer the temperature of the upper mantle — the layer of the Earth just below the crust. But estimates thus far are inconclusive, and scientists disagree about how widely temperatures vary beneath the surface.

    For their new study, Krein and her colleagues developed a new algorithm, called “ReversePetrogen”, that is designed to trace a rock’s chemical history back in time, to identify its original composition of elements and determine the temperature at which the rock initially melted below the surface.

    The algorithm is based on years of experiments carried out in Grove’s lab to reproduce and characterize the melting processes of the Earth’s interior. Researchers in the lab have heated up rocks of various compositions, reaching various temperatures and pressures, to observe their chemical evolution. From these experiments, the team has been able to derive equations — and ultimately, the new algorithm — to predict the relationships between a rock’s temperature, pressure, and chemical composition.

    Krein and her colleagues applied their new algorithm to rocks collected along the Earth’s ocean ridges — a system of undersea volcanoes spanning more than 70,000 kilometers in length. Ocean ridges are regions where tectonic plates are spread apart by the eruption of material from the Earth’s mantle — a process that is driven by underlying temperatures.

    “You could effectively make a model of the temperature of the entire interior of the Earth, based partly on the temperature at these ridges,” Krein says. “The question is, what is the data really telling us about the temperature variation in the mantle along the whole chain?”

    Mantle map

    The data the team analyzed include more than 13,500 samples collected along the length of the ocean ridge system over several decades, by multiple research cruises. Each sample in the dataset is of an erupted sea glass — lava that erupted in the ocean and was instantly chilled by the surrounding water into a pristine, preserved form.

    Scientists previously identified the chemical compositions of each glass in the dataset. Krein and her colleagues ran each sample’s chemical compositions through their algorithm to determine the temperature at which each glass originally melted in the mantle.

    In this way, the team was able to generate a map of mantle temperatures along the entire length of the ocean ridge system. From this map, they observed that much of the mantle is relatively homogenous, with an average temperature of around 1,350 degrees Celsius. There are however, “hotspots,” or regions along the ridge, where temperatures in the mantle appear significantly hotter, at around 1,600 degrees Celsius.

    “People think of hotspots as regions in the mantle where it’s hotter, and where material may be melting more, and potentially rising faster, and we don’t exactly know why, or how much hotter they are, or what the role of composition is at hotspots,” Krein says. “Some of these hotspots are on the ridge, and now we may get a sense of what the hotspot variation is globally using this new technique. That tells us something fundamental about the temperature of the Earth now, and now we can think of how it’s changed over time.”

    Krein adds: “Understanding these dynamics will help us better determine how continents grew and evolved on Earth, and when subduction and plate tectonics started — which are critical for complex life.”

    This research was supported, in part, by the National Science Foundation(US).

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    MIT Seal

    USPS “Forever” postage stamps celebrating Innovation at MIT.

    MIT Campus

    Massachusetts Institute of Technology (US) is a private land-grant research university in Cambridge, Massachusetts. The institute has an urban campus that extends more than a mile (1.6 km) alongside the Charles River. The institute also encompasses a number of major off-campus facilities such as the MIT Lincoln Laboratory (US), the MIT Bates Research and Engineering Center (US), and the Haystack Observatory (US), as well as affiliated laboratories such as the Broad Institute of MIT and Harvard(US) and Whitehead Institute (US).

    Founded in 1861 in response to the increasing industrialization of the United States, Massachusetts Institute of Technology (US) adopted a European polytechnic university model and stressed laboratory instruction in applied science and engineering. It has since played a key role in the development of many aspects of modern science, engineering, mathematics, and technology, and is widely known for its innovation and academic strength. It is frequently regarded as one of the most prestigious universities in the world.

    As of December 2020, 97 Nobel laureates, 26 Turing Award winners, and 8 Fields Medalists have been affiliated with MIT as alumni, faculty members, or researchers. In addition, 58 National Medal of Science recipients, 29 National Medals of Technology and Innovation recipients, 50 MacArthur Fellows, 80 Marshall Scholars, 3 Mitchell Scholars, 22 Schwarzman Scholars, 41 astronauts, and 16 Chief Scientists of the U.S. Air Force have been affiliated with Massachusetts Institute of Technology (US) . The university also has a strong entrepreneurial culture and MIT alumni have founded or co-founded many notable companies. Massachusetts Institute of Technology (US) is a member of the Association of American Universities (AAU).

    Foundation and vision

    In 1859, a proposal was submitted to the Massachusetts General Court to use newly filled lands in Back Bay, Boston for a “Conservatory of Art and Science”, but the proposal failed. A charter for the incorporation of the Massachusetts Institute of Technology, proposed by William Barton Rogers, was signed by John Albion Andrew, the governor of Massachusetts, on April 10, 1861.

    Rogers, a professor from the University of Virginia (US), wanted to establish an institution to address rapid scientific and technological advances. He did not wish to found a professional school, but a combination with elements of both professional and liberal education, proposing that:

    “The true and only practicable object of a polytechnic school is, as I conceive, the teaching, not of the minute details and manipulations of the arts, which can be done only in the workshop, but the inculcation of those scientific principles which form the basis and explanation of them, and along with this, a full and methodical review of all their leading processes and operations in connection with physical laws.”

    The Rogers Plan reflected the German research university model, emphasizing an independent faculty engaged in research, as well as instruction oriented around seminars and laboratories.

    Early developments

    Two days after Massachusetts Institute of Technology (US) was chartered, the first battle of the Civil War broke out. After a long delay through the war years, MIT’s first classes were held in the Mercantile Building in Boston in 1865. The new institute was founded as part of the Morrill Land-Grant Colleges Act to fund institutions “to promote the liberal and practical education of the industrial classes” and was a land-grant school. In 1863 under the same act, the Commonwealth of Massachusetts founded the Massachusetts Agricultural College, which developed as the University of Massachusetts Amherst (US)). In 1866, the proceeds from land sales went toward new buildings in the Back Bay.

    Massachusetts Institute of Technology (US) was informally called “Boston Tech”. The institute adopted the European polytechnic university model and emphasized laboratory instruction from an early date. Despite chronic financial problems, the institute saw growth in the last two decades of the 19th century under President Francis Amasa Walker. Programs in electrical, chemical, marine, and sanitary engineering were introduced, new buildings were built, and the size of the student body increased to more than one thousand.

    The curriculum drifted to a vocational emphasis, with less focus on theoretical science. The fledgling school still suffered from chronic financial shortages which diverted the attention of the MIT leadership. During these “Boston Tech” years, Massachusetts Institute of Technology (US) faculty and alumni rebuffed Harvard University (US) president (and former MIT faculty) Charles W. Eliot’s repeated attempts to merge MIT with Harvard College’s Lawrence Scientific School. There would be at least six attempts to absorb MIT into Harvard. In its cramped Back Bay location, MIT could not afford to expand its overcrowded facilities, driving a desperate search for a new campus and funding. Eventually, the MIT Corporation approved a formal agreement to merge with Harvard, over the vehement objections of MIT faculty, students, and alumni. However, a 1917 decision by the Massachusetts Supreme Judicial Court effectively put an end to the merger scheme.

    In 1916, the Massachusetts Institute of Technology (US) administration and the MIT charter crossed the Charles River on the ceremonial barge Bucentaur built for the occasion, to signify MIT’s move to a spacious new campus largely consisting of filled land on a one-mile-long (1.6 km) tract along the Cambridge side of the Charles River. The neoclassical “New Technology” campus was designed by William W. Bosworth and had been funded largely by anonymous donations from a mysterious “Mr. Smith”, starting in 1912. In January 1920, the donor was revealed to be the industrialist George Eastman of Rochester, New York, who had invented methods of film production and processing, and founded Eastman Kodak. Between 1912 and 1920, Eastman donated $20 million ($236.6 million in 2015 dollars) in cash and Kodak stock to MIT.

    Curricular reforms

    In the 1930s, President Karl Taylor Compton and Vice-President (effectively Provost) Vannevar Bush emphasized the importance of pure sciences like physics and chemistry and reduced the vocational practice required in shops and drafting studios. The Compton reforms “renewed confidence in the ability of the Institute to develop leadership in science as well as in engineering”. Unlike Ivy League schools, Massachusetts Institute of Technology (US) catered more to middle-class families, and depended more on tuition than on endowments or grants for its funding. The school was elected to the Association of American Universities (US)in 1934.

    Still, as late as 1949, the Lewis Committee lamented in its report on the state of education at Massachusetts Institute of Technology (US) that “the Institute is widely conceived as basically a vocational school”, a “partly unjustified” perception the committee sought to change. The report comprehensively reviewed the undergraduate curriculum, recommended offering a broader education, and warned against letting engineering and government-sponsored research detract from the sciences and humanities. The School of Humanities, Arts, and Social Sciences and the MIT Sloan School of Management were formed in 1950 to compete with the powerful Schools of Science and Engineering. Previously marginalized faculties in the areas of economics, management, political science, and linguistics emerged into cohesive and assertive departments by attracting respected professors and launching competitive graduate programs. The School of Humanities, Arts, and Social Sciences continued to develop under the successive terms of the more humanistically oriented presidents Howard W. Johnson and Jerome Wiesner between 1966 and 1980.

    Massachusetts Institute of Technology (US)‘s involvement in military science surged during World War II. In 1941, Vannevar Bush was appointed head of the federal Office of Scientific Research and Development and directed funding to only a select group of universities, including MIT. Engineers and scientists from across the country gathered at Massachusetts Institute of Technology (US)’s Radiation Laboratory, established in 1940 to assist the British military in developing microwave radar. The work done there significantly affected both the war and subsequent research in the area. Other defense projects included gyroscope-based and other complex control systems for gunsight, bombsight, and inertial navigation under Charles Stark Draper’s Instrumentation Laboratory; the development of a digital computer for flight simulations under Project Whirlwind; and high-speed and high-altitude photography under Harold Edgerton. By the end of the war, Massachusetts Institute of Technology (US) became the nation’s largest wartime R&D contractor (attracting some criticism of Bush), employing nearly 4000 in the Radiation Laboratory alone and receiving in excess of $100 million ($1.2 billion in 2015 dollars) before 1946. Work on defense projects continued even after then. Post-war government-sponsored research at MIT included SAGE and guidance systems for ballistic missiles and Project Apollo.

    These activities affected Massachusetts Institute of Technology (US) profoundly. A 1949 report noted the lack of “any great slackening in the pace of life at the Institute” to match the return to peacetime, remembering the “academic tranquility of the prewar years”, though acknowledging the significant contributions of military research to the increased emphasis on graduate education and rapid growth of personnel and facilities. The faculty doubled and the graduate student body quintupled during the terms of Karl Taylor Compton, president of Massachusetts Institute of Technology (US) between 1930 and 1948; James Rhyne Killian, president from 1948 to 1957; and Julius Adams Stratton, chancellor from 1952 to 1957, whose institution-building strategies shaped the expanding university. By the 1950s, Massachusetts Institute of Technology (US) no longer simply benefited the industries with which it had worked for three decades, and it had developed closer working relationships with new patrons, philanthropic foundations and the federal government.

    In late 1960s and early 1970s, student and faculty activists protested against the Vietnam War and Massachusetts Institute of Technology (US)’s defense research. In this period Massachusetts Institute of Technology (US)’s various departments were researching helicopters, smart bombs and counterinsurgency techniques for the war in Vietnam as well as guidance systems for nuclear missiles. The Union of Concerned Scientists was founded on March 4, 1969 during a meeting of faculty members and students seeking to shift the emphasis on military research toward environmental and social problems. Massachusetts Institute of Technology (US) ultimately divested itself from the Instrumentation Laboratory and moved all classified research off-campus to the MIT (US) Lincoln Laboratory facility in 1973 in response to the protests. The student body, faculty, and administration remained comparatively unpolarized during what was a tumultuous time for many other universities. Johnson was seen to be highly successful in leading his institution to “greater strength and unity” after these times of turmoil. However six Massachusetts Institute of Technology (US) students were sentenced to prison terms at this time and some former student leaders, such as Michael Albert and George Katsiaficas, are still indignant about MIT’s role in military research and its suppression of these protests. (Richard Leacock’s film, November Actions, records some of these tumultuous events.)

    In the 1980s, there was more controversy at Massachusetts Institute of Technology (US) over its involvement in SDI (space weaponry) and CBW (chemical and biological warfare) research. More recently, Massachusetts Institute of Technology (US)’s research for the military has included work on robots, drones and ‘battle suits’.

    Recent history

    Massachusetts Institute of Technology (US) has kept pace with and helped to advance the digital age. In addition to developing the predecessors to modern computing and networking technologies, students, staff, and faculty members at Project MAC, the Artificial Intelligence Laboratory, and the Tech Model Railroad Club wrote some of the earliest interactive computer video games like Spacewar! and created much of modern hacker slang and culture. Several major computer-related organizations have originated at MIT since the 1980s: Richard Stallman’s GNU Project and the subsequent Free Software Foundation were founded in the mid-1980s at the AI Lab; the MIT Media Lab was founded in 1985 by Nicholas Negroponte and Jerome Wiesner to promote research into novel uses of computer technology; the World Wide Web Consortium standards organization was founded at the Laboratory for Computer Science in 1994 by Tim Berners-Lee; the MIT OpenCourseWare project has made course materials for over 2,000 Massachusetts Institute of Technology (US) classes available online free of charge since 2002; and the One Laptop per Child initiative to expand computer education and connectivity to children worldwide was launched in 2005.

    Massachusetts Institute of Technology (US) was named a sea-grant college in 1976 to support its programs in oceanography and marine sciences and was named a space-grant college in 1989 to support its aeronautics and astronautics programs. Despite diminishing government financial support over the past quarter century, MIT launched several successful development campaigns to significantly expand the campus: new dormitories and athletics buildings on west campus; the Tang Center for Management Education; several buildings in the northeast corner of campus supporting research into biology, brain and cognitive sciences, genomics, biotechnology, and cancer research; and a number of new “backlot” buildings on Vassar Street including the Stata Center. Construction on campus in the 2000s included expansions of the Media Lab, the Sloan School’s eastern campus, and graduate residences in the northwest. In 2006, President Hockfield launched the MIT Energy Research Council to investigate the interdisciplinary challenges posed by increasing global energy consumption.

    In 2001, inspired by the open source and open access movements, Massachusetts Institute of Technology (US) launched OpenCourseWare to make the lecture notes, problem sets, syllabi, exams, and lectures from the great majority of its courses available online for no charge, though without any formal accreditation for coursework completed. While the cost of supporting and hosting the project is high, OCW expanded in 2005 to include other universities as a part of the OpenCourseWare Consortium, which currently includes more than 250 academic institutions with content available in at least six languages. In 2011, Massachusetts Institute of Technology (US) announced it would offer formal certification (but not credits or degrees) to online participants completing coursework in its “MITx” program, for a modest fee. The “edX” online platform supporting MITx was initially developed in partnership with Harvard and its analogous “Harvardx” initiative. The courseware platform is open source, and other universities have already joined and added their own course content. In March 2009 the Massachusetts Institute of Technology (US) faculty adopted an open-access policy to make its scholarship publicly accessible online.

    Massachusetts Institute of Technology (US) has its own police force. Three days after the Boston Marathon bombing of April 2013, MIT Police patrol officer Sean Collier was fatally shot by the suspects Dzhokhar and Tamerlan Tsarnaev, setting off a violent manhunt that shut down the campus and much of the Boston metropolitan area for a day. One week later, Collier’s memorial service was attended by more than 10,000 people, in a ceremony hosted by the Massachusetts Institute of Technology (US) community with thousands of police officers from the New England region and Canada. On November 25, 2013, Massachusetts Institute of Technology (US) announced the creation of the Collier Medal, to be awarded annually to “an individual or group that embodies the character and qualities that Officer Collier exhibited as a member of the Massachusetts Institute of Technology (US) community and in all aspects of his life”. The announcement further stated that “Future recipients of the award will include those whose contributions exceed the boundaries of their profession, those who have contributed to building bridges across the community, and those who consistently and selflessly perform acts of kindness”.

    In September 2017, the school announced the creation of an artificial intelligence research lab called the MIT-IBM Watson AI Lab. IBM will spend $240 million over the next decade, and the lab will be staffed by MIT and IBM scientists. In October 2018 MIT announced that it would open a new Schwarzman College of Computing dedicated to the study of artificial intelligence, named after lead donor and The Blackstone Group CEO Stephen Schwarzman. The focus of the new college is to study not just AI, but interdisciplinary AI education, and how AI can be used in fields as diverse as history and biology. The cost of buildings and new faculty for the new college is expected to be $1 billion upon completion.

    The Caltech/MIT Advanced aLIGO (US) was designed and constructed by a team of scientists from California Institute of Technology (US), Massachusetts Institute of Technology (US), and industrial contractors, and funded by the National Science Foundation (US) .

    MIT/Caltech Advanced aLigo .

    It was designed to open the field of gravitational-wave astronomy through the detection of gravitational waves predicted by general relativity. Gravitational waves were detected for the first time by the LIGO detector in 2015. For contributions to the LIGO detector and the observation of gravitational waves, two Caltech physicists, Kip Thorne and Barry Barish, and Massachusetts Institute of Technology (US) physicist Rainer Weiss won the Nobel Prize in physics in 2017. Weiss, who is also an Massachusetts Institute of Technology (US) graduate, designed the laser interferometric technique, which served as the essential blueprint for the LIGO.

    The mission of Massachusetts Institute of Technology (US) is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the Massachusetts Institute of Technology (US) community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

     
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