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  • richardmitnick 8:55 am on April 24, 2022 Permalink | Reply
    Tags: "These Tiny Crystals Are 'Time Capsules' of Earth's Early Plate Tectonic Activity", A chronological series of 33 microscopic zircon crystals dating from 4.15 to 3.3 billion years ago was found in an ancient block of Earth's crust found in the Barberton Greenstone Belt in South Africa, , , , , Mineral crystals can act as a sort of time capsule that contains information about the conditions in which they formed., Paleogeology, ,   

    From Harvard University via Science Alert(AU): “These Tiny Crystals Are ‘Time Capsules’ of Earth’s Early Plate Tectonic Activity” 

    From Harvard University

    via

    ScienceAlert

    Science Alert(AU)

    23 APRIL 2022
    MICHELLE STARR

    1
    A large zircon crystal embedded in calcite. Credit: Rob Lavinsky/iRocks.com/Wikimedia Commons/CC BY-SA-3.0.

    Tiny crystals of zircon dated to 3.8 billion years ago contain the earliest geochemical evidence yet for plate tectonic activity here on Earth.

    Isotopes and trace elements preserved in the crystals show evidence that they formed under subduction conditions – when the edge of one tectonic plate slips beneath the edge of the adjacent plate, creating specific conditions. This provides new constraints on when plate tectonics emerged on Earth.

    Because plate tectonics played a key role in creating the conditions for life on Earth, altering the compositions of the oceans and atmosphere, understanding when and how they emerged is also important for understanding how we got here, and what makes a planet habitable.

    Understanding the geology of early Earth is something of a challenge. The crust of our world has been pretty dynamic over its 4.6-billion-year history, and the only direct record of the Hadean eon – between 4.6 and 4 billion years ago – can be found in crystals of the mineral zircon.

    These crystals seem to survive the ravages of time but rarely: just 12 locations on Earth have yielded the ancient grains, three or fewer in most locations.

    Recently, however, a team of geologists unearthed an amazing treasure. A chronological series of 33 microscopic zircon crystals, dating from 4.15 to 3.3 billion years ago, was found in an ancient block of Earth’s crust found in the Barberton Greenstone Belt in South Africa.

    The series provided a rare opportunity to probe the changing conditions of early Earth, from the Hadean through the Eoarchaeon era, which ran from 4 to 3.6 billion years ago.

    Mineral crystals can act as a sort of time capsule that contains information about the conditions in which they formed, and zircon crystals in particular can be extremely valuable for this scientific purpose. Isotopes of the metal hafnium and trace elements found in zircon can be used to make inferences about the rocks from which they crystallized.

    A team of scientists led by geologist Nadja Drabon of Harvard University studied the Greenstone Belt zircons to reconstruct a timeline of the conditions under which they formed. They found that from about 3.8 billion years ago onwards, the crystals had hafnium and trace element signatures similar to modern rocks formed in subduction zones – at the edges of tectonic plates.

    This suggests that plate tectonics were active at the time those crystals formed, the researchers said.

    “When I say plate tectonics, I’m specifically referring to an arc setting, when one plate goes under another and you have all that volcanism – think of the Andes, for example, and the Ring of Fire,” Drabon said.

    “At 3.8 billion years [ago] there is a dramatic shift where the crust is destabilized, we have new rocks forming and we see geochemical signatures becoming more and more similar to what we see in modern plate tectonics.”

    Fascinatingly, zircon crystals older than that 3.8 billion-year cut-off were not formed in a subduction zone setting, but likely crystallized in a Hadean “protocrust” that formed from remelted mantle material, before the mantle was depleted of basaltic melt elements by tectonic processes.

    The team then compared their findings to zircon crystals dating to around the same time from around the world to make sure they weren’t just observing a localized phenomenon. These other zircons showed similar transitions.

    It’s difficult to know exactly if the tiny grains all point to the evolution of our world towards plate tectonics, but the results definitely suggest that a global change was occurring.

    “We see evidence for a significant change on the Earth around 3.8 to 3.6 billion years ago and evolution toward plate tectonics is one clear possibility,” Drabon said.

    “The record we have for the earliest Earth is really limited, but just seeing a similar transition in so many different places makes it really feasible that it might have been a global change in crustal processes. Some kind of reorganization was happening on Earth.”

    The research has been published in AGU Advances.

    See the full article here .

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    Harvard University campus

    Harvard University is the oldest institution of higher education in the United States, established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. It was named after the College’s first benefactor, the young minister John Harvard of Charlestown, who upon his death in 1638 left his library and half his estate to the institution. A statue of John Harvard stands today in front of University Hall in Harvard Yard, and is perhaps the University’s bestknown landmark.

    Harvard University has 12 degree-granting Schools in addition to the Radcliffe Institute for Advanced Study. The University has grown from nine students with a single master to an enrollment of more than 20,000 degree candidates including undergraduate, graduate, and professional students. There are more than 360,000 living alumni in the U.S. and over 190 other countries.

    The Massachusetts colonial legislature, the General Court, authorized Harvard University’s founding. In its early years, Harvard College primarily trained Congregational and Unitarian clergy, although it has never been formally affiliated with any denomination. Its curriculum and student body were gradually secularized during the 18th century, and by the 19th century, Harvard University (US) had emerged as the central cultural establishment among the Boston elite. Following the American Civil War, President Charles William Eliot’s long tenure (1869–1909) transformed the college and affiliated professional schools into a modern research university; Harvard became a founding member of the Association of American Universities in 1900. James B. Conant led the university through the Great Depression and World War II; he liberalized admissions after the war.

    The university is composed of ten academic faculties plus the Radcliffe Institute for Advanced Study. Arts and Sciences offers study in a wide range of academic disciplines for undergraduates and for graduates, while the other faculties offer only graduate degrees, mostly professional. Harvard has three main campuses: the 209-acre (85 ha) Cambridge campus centered on Harvard Yard; an adjoining campus immediately across the Charles River in the Allston neighborhood of Boston; and the medical campus in Boston’s Longwood Medical Area. Harvard University’s endowment is valued at $41.9 billion, making it the largest of any academic institution. Endowment income helps enable the undergraduate college to admit students regardless of financial need and provide generous financial aid with no loans The Harvard Library is the world’s largest academic library system, comprising 79 individual libraries holding about 20.4 million items.

    Harvard University has more alumni, faculty, and researchers who have won Nobel Prizes (161) and Fields Medals (18) than any other university in the world and more alumni who have been members of the U.S. Congress, MacArthur Fellows, Rhodes Scholars (375), and Marshall Scholars (255) than any other university in the United States. Its alumni also include eight U.S. presidents and 188 living billionaires, the most of any university. Fourteen Turing Award laureates have been Harvard affiliates. Students and alumni have also won 10 Academy Awards, 48 Pulitzer Prizes, and 108 Olympic medals (46 gold), and they have founded many notable companies.

    Colonial

    Harvard University was established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. In 1638, it acquired British North America’s first known printing press. In 1639, it was named Harvard College after deceased clergyman John Harvard, an alumnus of the University of Cambridge (UK) who had left the school £779 and his library of some 400 volumes. The charter creating the Harvard Corporation was granted in 1650.

    A 1643 publication gave the school’s purpose as “to advance learning and perpetuate it to posterity, dreading to leave an illiterate ministry to the churches when our present ministers shall lie in the dust.” It trained many Puritan ministers in its early years and offered a classic curriculum based on the English university model—many leaders in the colony had attended the University of Cambridge—but conformed to the tenets of Puritanism. Harvard University has never affiliated with any particular denomination, though many of its earliest graduates went on to become clergymen in Congregational and Unitarian churches.

    Increase Mather served as president from 1681 to 1701. In 1708, John Leverett became the first president who was not also a clergyman, marking a turning of the college away from Puritanism and toward intellectual independence.

    19th century

    In the 19th century, Enlightenment ideas of reason and free will were widespread among Congregational ministers, putting those ministers and their congregations in tension with more traditionalist, Calvinist parties. When Hollis Professor of Divinity David Tappan died in 1803 and President Joseph Willard died a year later, a struggle broke out over their replacements. Henry Ware was elected to the Hollis chair in 1805, and the liberal Samuel Webber was appointed to the presidency two years later, signaling the shift from the dominance of traditional ideas at Harvard to the dominance of liberal, Arminian ideas.

    Charles William Eliot, president 1869–1909, eliminated the favored position of Christianity from the curriculum while opening it to student self-direction. Though Eliot was the crucial figure in the secularization of American higher education, he was motivated not by a desire to secularize education but by Transcendentalist Unitarian convictions influenced by William Ellery Channing and Ralph Waldo Emerson.

    20th century

    In the 20th century, Harvard University’s reputation grew as a burgeoning endowment and prominent professors expanded the university’s scope. Rapid enrollment growth continued as new graduate schools were begun and the undergraduate college expanded. Radcliffe College, established in 1879 as the female counterpart of Harvard College, became one of the most prominent schools for women in the United States. Harvard University (US) became a founding member of the Association of American Universities in 1900.

    The student body in the early decades of the century was predominantly “old-stock, high-status Protestants, especially Episcopalians, Congregationalists, and Presbyterians.” A 1923 proposal by President A. Lawrence Lowell that Jews be limited to 15% of undergraduates was rejected, but Lowell did ban blacks from freshman dormitories.

    President James B. Conant reinvigorated creative scholarship to guarantee Harvard University’s preeminence among research institutions. He saw higher education as a vehicle of opportunity for the talented rather than an entitlement for the wealthy, so Conant devised programs to identify, recruit, and support talented youth. In 1943, he asked the faculty to make a definitive statement about what general education ought to be, at the secondary as well as at the college level. The resulting Report, published in 1945, was one of the most influential manifestos in 20th century American education.

    Between 1945 and 1960, admissions were opened up to bring in a more diverse group of students. No longer drawing mostly from select New England prep schools, the undergraduate college became accessible to striving middle class students from public schools; many more Jews and Catholics were admitted, but few blacks, Hispanics, or Asians. Throughout the rest of the 20th century, Harvard became more diverse.

    Harvard University’s graduate schools began admitting women in small numbers in the late 19th century. During World War II, students at Radcliffe College (which since 1879 had been paying Harvard University professors to repeat their lectures for women) began attending Harvard University classes alongside men. Women were first admitted to the medical school in 1945. Since 1971, Harvard University has controlled essentially all aspects of undergraduate admission, instruction, and housing for Radcliffe women. In 1999, Radcliffe was formally merged into Harvard University.

    21st century

    Drew Gilpin Faust, previously the dean of the Radcliffe Institute for Advanced Study, became Harvard University’s first woman president on July 1, 2007. She was succeeded by Lawrence Bacow on July 1, 2018.

     
  • richardmitnick 8:26 pm on April 20, 2022 Permalink | Reply
    Tags: "Eclogite samples found in China push modern-type subduction events back to 2.5 billion years ago", , , , , , Paleogeology   

    Fromphys.org: “Eclogite samples found in China push modern-type subduction events back to 2.5 billion years ago” 

    Fromphys.org

    April 20, 2022
    Bob Yirka

    1
    Outcrop of Archean eclogite (dark layer, with red garnet and green pyroxene) interlayered with garnet-bearing metagabbro from the Shangying location. Credit: Lu Wang.

    A team of researchers from The China University of Geosciences[中国地质大学(武汉)](CN), has concluded that eclogite samples found at the northern Central Orogenic Belt within the North China Craton, show that modern-type subduction events occurred on Earth as far back as 2.5 billion years ago. They published their work in PNAS.

    As the researchers note, Earth scientists have not been able to pinpoint the time period when modern-type subduction events began occurring. Many have suggested that it likely began approximately 2.1 billion years ago because no evidence of it occurring any earlier than that has been found. In this new effort, the researchers have found evidence showing that it goes back at least 2.5 billion years.

    Prior research has shown that eclogite forms when one of the planet’s tectonic plates slides under another. Researchers at China University of Geosciences have been studying Archean eon rocks in the Central Orogenic Belt for approximately 20 years. The site runs for approximately 1,600 kilometers. Such work has shown that the mountain belt was formed due to subduction events. Researchers there have, for example, found ophiolites in the rock—evidence that the material once resided on the ocean floor. They have also found mélanges in spots that appear to be the meeting point between plates. But it was study of eclogites found at the site by this most recent team that showed evidence of modern-type subduction events occurring at least 2.5 billion years ago. Analysis of the samples also showed evidence of metamorphosis as the rock changed due to the heat and pressure of the subduction event.

    2
    Cut slab of Archean eclogite with red garnet and green pyroxene from the Shangying location. Credit: Lu Wang.

    The researchers found that the eclogite samples were originally formed as part of an ocean ridge that moved until reaching the subduction zone. After being pushed under a plate, the rock was exposed to temperatures between 792 and 890 C° and pressure as high as 19.8 to 24.5 kilobars. Such numbers suggested the rock had been pushed as far down as 65 km below the surface before later being pushed back up to the surface.

    See the full article here .

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    About Science X in 100 words
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  • richardmitnick 11:13 am on April 12, 2022 Permalink | Reply
    Tags: "An Atacama Super-Quake We Never Knew About Sent Humans Into Hiding For 1000 Years", A gigantic tsunami-unleashing earthquake that struck northern Chile 3800 years ago wreaked such devastation on coastal populations that it took 1000 years for humans to return to the shore., , , , , , Paleogeology, , The ancient super-quake would have had a magnitude of around 9.5., The quake generated a tsunami that hurled boulders hundreds of meters inland in New Zealand which is thousands of miles and an ocean away., The University of New South Wales(AU)   

    From The University of New South Wales(AU) and The University of Chile [Universidad de Chile](CL) via Science Alert(AU): “An Atacama Super-Quake We Never Knew About Sent Humans Into Hiding For 1000 Years” 

    U NSW bloc

    From The University of New South Wales(AU)

    and

    U Chile Bloc

    The University of Chile [Universidad de Chile](CL)

    via

    ScienceAlert

    Science Alert(AU)

    12 APRIL 2022
    PETER DOCKRILL

    A gigantic tsunami-unleashing earthquake that struck northern Chile 3800 years ago wreaked such devastation on coastal populations, it took 1,000 years for humans to return to the shore, scientists say.

    The ancient super-quake would have had a magnitude of around 9.5, and was so powerful it generated a tsunami that hurled boulders hundreds of meters inland in New Zealand, which is thousands of miles – and an entire ocean – away.

    The discovery is evidenced by uplifted land structures (aka littoral deposits) and samples of marine rocks, shells, and sea life washed far ashore by tsunami waves into the higher stretches of Chile’s Atacama Desert. It serves as a grim warning of the destructive potential of major tsunamigenic earthquakes that may have previously escaped our notice.

    “We found evidence of marine sediments and a lot of beasties that would have been living quietly in the sea before being thrown inland,” says geologist and tsunami specialist James Goff from the University of New South Wales, Australia.

    “And we found all these very high up and a long way inland so it could not have been a storm that put them there.”

    2
    Tsunami deposits visible in a trench. Credit: The University of Southampton (UK).

    The research team, led by anthropologist Diego Salazar from The University of Chile[Universidad de Chile](CL), conducted several years of research in the Atacama Desert region, which is particularly vulnerable to megathrust earthquakes due to its proximity to the convergence of the Nazca and South American tectonic plates, with the former being subducted under the latter.

    This phenomenon and its seismic backlash is what led to the most powerful earthquake on record, the 1960 Valdivia earthquake in southern Chile; thousands of years prior, it seems the same tectonic tensions led to an equally diabolical yet undocumented precursor in the north of the country.

    “It had been thought that there could not be an event of that size in the north of the country simply because you could not get a long enough rupture,” says Goff.

    “But we have now found evidence of a rupture that’s about one thousand kilometers long just off the Atacama Desert coast, and that is massive.”

    In their investigations, the researchers used radiocarbon dating to get a sense of the age of the littoral deposits, which stretch over some 600 kilometers (about 370 miles) of Chile’s coastline.

    Readings from several of the deposit sites suggest the existence of a “tectonic event that would have uplifted littoral deposits all along the study region, generated a paleotsunami, and triggered social disruption at a regional scale,” the researchers write in their paper.

    2
    Collapsed stone structure. Credit: Gabriel Easton.

    At the time of the event, the people living in this part of the world were hunter-gatherer communities. Archaeological evidence suggests the tsunami wave generated by the quake toppled their stone structures – and not just once, but twice, with a strong current of tsunami backwash wreaking havoc as it flowed back out to the sea.

    The effects on any people lucky enough to have survived the immediate disaster were long-lasting, with evidence suggesting the area remained uninhabited by human populations for as long as 1,000 years, despite people living on this stretch of coastline for nearly 10 millennia before the crisis.

    “The local population there were left with nothing,” says Goff. “Our archaeological work found that a huge social upheaval followed as communities moved inland beyond the reach of tsunamis.”

    With time and the passing of dozens of generations, the local people’s boldness (or perhaps forgetfulness) grew, and people eventually made their way back to the ocean about 1,000 years later.

    “The abandonment of previously occupied areas and changes in the mobility patterns and spatial arrangements of settlements and cemeteries were probably resilience strategies developed by hunter-gatherer societies,” the researchers write.

    “However, knowledge of these giant events and their consequences seems to wane over the passage of time.”

    Aside from filling the gaps in our historical understanding of this gigantic event – an earthquake about as powerful as anything known to humanity – the research is a cautionary note about the risks similarly powerful megathrust quakes might pose in the future, the researchers say.

    “While this had a major impact on people in Chile, the South Pacific islands were uninhabited when they took a pummeling from the tsunami 3,800 years ago,” Goff says.

    “But they are all well-populated now, and many are popular tourist destinations, so when such an event occurs next time the consequences could be catastrophic unless we learn from these findings.”

    The findings are reported in Science Advances.

    See the full article here .


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    U Chile Campus

    The University of Chile[Universidad de Chile](CL) is the largest and oldest institution of higher education in Chile and one of the oldest in Latin America. Founded in 1842 as the replacement and continuation of the former colonial Royal University of San Felipe (1738) (Spanish: Real Universidad de San Felipe), the university is often called Casa de Bello (House of Bello) in honor of its first president, Andrés Bello. Notable alumni include two Nobel laureates (Pablo Neruda and Gabriela Mistral) and twenty Chilean presidents among many others.

    U NSW Campus

    The The University of New South Wales is an Australian public university with its largest campus in the Sydney suburb of Kensington.

    Established in 1949, UNSW is a research university, ranked 44th in the world in the 2021 QS World University Rankings and 67th in the world in the 2021 Times Higher Education World University Rankings. UNSW is one of the founding members of the Group of Eight, a coalition of Australian research-intensive universities, and of Universitas 21, a global network of research universities. It has international exchange and research partnerships with over 200 universities around the world.

    According to the 2021 QS World University Rankings by Subject, UNSW is ranked top 20 in the world for Law, Accounting and Finance, and 1st in Australia for Mathematics, Engineering and Technology. UNSW also leads Australia in Medicine, where the median ATAR (Australian university entrance examination results) of its Medical School students is higher than any other Australian medical school. UNSW enrolls the highest number of Australia’s top 500 high school students academically, and produces more millionaire graduates than any other Australian university.

    The university comprises seven faculties, through which it offers bachelor’s, master’s and doctoral degrees. The main campus is in the Sydney suburb of Kensington, 7 kilometres (4.3 mi) from the Sydney CBD. The creative arts faculty, UNSW Art & Design, is located in Paddington, and subcampuses are located in the Sydney CBD as well as several other suburbs, including Randwick and Coogee. Research stations are located throughout the state of New South Wales.

    The university’s second largest campus, known as UNSW Canberra at ADFA (formerly known as UNSW at ADFA), is situated in Canberra, in the Australian Capital Territory (ACT). ADFA is the military academy of the Australian Defense Force, and UNSW Canberra is the only national academic institution with a defense focus.

    Research centres

    The university has a number of purpose-built research facilities, including:

    UNSW Lowy Cancer Research Centre is Australia’s first facility bringing together researchers in childhood and adult cancers, as well as one of the country’s largest cancer-research facilities, housing up to 400 researchers.

    The Mark Wainwright Analytical Centre is a centre for the faculties of science, medicine, and engineering. It is used to study the structure and composition of biological, chemical, and physical materials.

    UNSW Canberra Cyber is a cyber-security research and teaching centre.

    The Sino-Australian Research Centre for Coastal Management (SARCCM) has a multidisciplinary focus, and works collaboratively with the Ocean University of China [中國海洋大學](CN) in coastal management research.

     
  • richardmitnick 9:54 am on March 27, 2022 Permalink | Reply
    Tags: , , , , , Paleogeology,   

    From New York University: “The Earth Has a Pulse—A 27.5-Million-Year Cycle of Geological Activity” 

    NYU BLOC

    From New York University

    3.27.22 Re-issue [Originally issued Jun 18, 2021 but worth another look]

    Analysis of 260 Million Years of Major Geological Events Finds Recurring Clusters 27.5 Million Years Apart.

    Rachel Harrison
    rachel.harrison@nyu.edu
    (212) 998-6797

    1
    © Getty Images

    Geologic activity on Earth appears to follow a 27.5-million-year cycle, giving the planet a “pulse,” according to a new study published in the journal Geoscience Frontiers.

    Another study published in late 2020 [Historical Biology] by the same authors suggested that this 27.5-million-year mark is when mass extinctions happen, too.

    “Many geologists believe that geological events are random over time. But our study provides statistical evidence for a common cycle, suggesting that these geologic events are correlated and not random,” said Michael Rampino, a geologist and professor in New York University’s Department of Biology, as well as the study’s lead author.

    Over the past five decades, researchers have proposed cycles of major geological events—including volcanic activity and mass extinctions on land and sea—ranging from roughly 26 to 36 million years. But early work on these correlations in the geological record was hampered by limitations in the age-dating of geologic events, which prevented scientists from conducting quantitative investigations.

    However, there have been significant improvements in radio-isotopic dating techniques and changes in the geologic timescale, leading to new data on the timing of past events. Using the latest age-dating data available, Rampino and his colleagues compiled updated records of major geological events over the last 260 million years and conducted new analyses.

    The team analyzed the ages of 89 well-dated major geological events of the last 260 million years. These events include marine and land extinctions, major volcanic outpourings of lava called flood-basalt eruptions, events when oceans were depleted of oxygen, sea-level fluctuations, and changes or reorganization in the Earth’s tectonic plates.

    They found that these global geologic events are generally clustered at 10 different timepoints over the 260 million years, grouped in peaks or pulses of roughly 27.5 million years apart. The most recent cluster of geological events was approximately 7 million years ago, suggesting that the next pulse of major geological activity is more than 20 million years in the future.

    2

    The researchers posit that these pulses may be a function of cycles of activity in the Earth’s interior—geophysical processes related to the dynamics of plate tectonics and climate. However, similar cycles in the Earth’s orbit in space might also be pacing these events.

    “Whatever the origins of these cyclical episodes, our findings support the case for a largely periodic, coordinated, and intermittently catastrophic geologic record, which is a departure from the views held by many geologists,” explained Rampino.

    In addition to Rampino, study authors include Yuhong Zhu of NYU’s Center for Data Science and Ken Caldeira of the Carnegie Institution for Science.

    See the full article here .

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    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 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.

     
  • richardmitnick 9:15 pm on March 16, 2022 Permalink | Reply
    Tags: "Ancient ice reveals scores of gigantic volcanic eruptions", , , , Paleogeology, Paleovolcanology, , , ,   

    From The University of Copenhagen [Københavns Universitet](DK) and The Niels Bohr Institute [Niels Bohr Institutet] (DK): “Ancient ice reveals scores of gigantic volcanic eruptions” 

    From The University of Copenhagen [Københavns Universitet](DK)

    and

    Niels Bohr Institute bloc

    The Niels Bohr Institute [Niels Bohr Institutet] (DK)

    16 March 2022

    Anders Svensson
    Associate Professor
    Niels Bohr Institute
    University of Copenhagen
    as@nbi.ku.dk
    +45 35 32 06 16

    Maria Hornbek
    Journalist
    Faculty of Science
    University of Copenhagen
    maho@science.ku.dk
    +45 22 95 42 83

    16 March 2022

    Volcanoes

    Ice cores drilled in Antarctica and Greenland have revealed gigantic volcanic eruptions during the last ice age. Sixty-nine of these were larger than any eruption in modern history. According to the University of Copenhagen physicists behind the research, these eruptions can teach us about our planet’s sensitivity to climate change.

    For many people, the mention of a volcanic eruption conjures up doomsday scenarios that include deafening explosions, dark ash billowing into the stratosphere and gloopy lava burying everything in its path as panicked humans run for their lives. While such an eruption could theoretically happen tomorrow, we have had to make do with disaster films and books when it comes to truly massive volcanic eruptions in the modern era.

    “We haven’t experienced any of history’s largest volcanic eruptions. We can see that now. Eyjafjellajökull, which paralysed European air traffic in 2010, pales in comparison to the eruptions we identified further back in time.

    1
    Eruption at Fimmvörðuháls at dusk.
    27 March 2010. Credit: Boaworm

    Many of these were larger than any eruption over the last 2,500 years,” says Associate Professor Anders Svensson of the University of Copenhagen’s Niels Bohr Institute.

    By comparing ice cores drilled in Antarctica and Greenland, he and his fellow researchers managed to estimate the quantity and intensity of volcanic eruptions over the last 60,000 years. Estimates of volcanic eruptions more than 2,500 years ago have been associated with great uncertainty and a lack of precision, until now.

    ____________________________________________
    FACT BOX: SELECTION OF KNOWN VOLCANIC ERUPTIONS

    Volcanic eruptions are classified by their size on the so-called Volcanic Explosivity Index (VEI), which ranges from 1-8.

    Etna, Italy (1669): 3 on the VEI scale
    Eyjafjellajökul, Iceland (2010): 4 on the VEI scale
    Vesuvius, Italy (year 79): 5 on the VEI scale
    Laki, Iceland (1783): 6 on the VEI scale
    Krakatau, Indonesia (1883): 6 on the VEI scale
    Tambora, Indonesia (1815): 7 on the VEI scale
    Lake Taupo, New Zealand (26,500 years ago): 8 on the VEI scale
    Toba, Indonesia (74,000 years ago): 8 on the VEI scale
    ____________________________________________

    Sixty-nine eruptions larger than Mount Tambora

    Eighty-five of the volcanic eruptions identified by the researchers were large global eruptions. Sixty-nine of these are estimated to be larger than the 1815 eruption of Mount Tambora in Indonesia – the largest volcanic eruption in recorded human history. So much sulfuric acid was ejected into the stratosphere by the Tambora eruption that it blocked sunlight and caused global cooling in the years that followed. The eruption also caused tsunamis, drought, famine and at least 80,000 deaths.

    “To reconstruct ancient volcanic eruptions, ice cores offer a few advantages over other methods. Whenever a really large eruption occurs, sulfuric acid is ejected into the upper atmosphere, which is then distributed globally – including onto Greenland and Antarctica. We can estimate the size of an eruption by looking at the amount of sulfuric acid that has fallen,” explains Anders Svensson.

    In a previous study, the researchers managed to synchronize ice cores from Antarctica and Greenland – i.e., to date the respective core layers on the same time scale. By doing so, they were able to compare sulphur residues in ice and deduce when sulfuric acid spread to both poles after globally significant eruptions.

    2
    Anders Svensson inspecting an icecore in Greenland (credit: NEEM [North Greenland Eemian Ice Drilling])

    When will it happen again?

    “The new 60,000-year timeline of volcanic eruptions supplies us with better statistics than ever before. Now we can see that many more of these great eruptions occurred during the prehistoric Ice Age than in modern times. Because large eruptions are relatively rare, a long timeline is needed to know when they occur. That is what we now have,” says Anders Svensson.

    One may be left wondering when the next of these massive eruptions will occur. But Svensson isn’t ready to make any concrete predictions:

    “Three eruptions of the largest known category occurred during the entire period we studied, so-called VEI-8 eruptions (see fact box). So, we can expect more at some point, but we just don’t know if that will be in a hundred or a few thousand years. Tambora sized eruptions appears to erupt once or twice every thousand years, so the wait for that may be shorter.”

    How was climate affected?

    When powerful enough, volcanic eruptions can affect global climate, where there is typically a 5-10- year period of cooling. As such, there is great interest in mapping the major eruptions of the past – as they can help us look into the future.

    “Ice cores contain information about temperatures before and after the eruptions, which allows us to calculate the effect on climate. As large eruptions tell us a lot about how sensitive our planet is to changes in the climate system, they can be useful for climate predictions,” explains Anders Svensson.

    Determining Earth’s climate sensitivity is an Achilles heel of current climate models. Svensson concludes:

    “The current IPCC models do not have a firm grasp of climate sensitivity – i.e., what the effect of a doubling of CO2 in the atmosphere will be. Vulcanism can supply us with answers as to how much temperature changes when Earths atmospheric radiation budget changes, whether due to CO2 or a blanket of sulphur particles. So, when we have estimated the effects of large volcanic eruptions on climate, we will be able to use the result to improve climate models.”

    The recent study is published in the journal, Climate of the Past.

    The researchers who contributed to the study are: Jiamei Lin, Anders Svensson, Christine S. Hvidberg, Johannes Lohmann, Steffen Kristiansen, Dorthe Dahl-Jensen, Jørgen P. Steffensen, Sune O. Rasmussen, Eliza Cook, Helle Astrid Kjær and Bo M. Vinther from the Niels Bohr Institute at the University of Copenhagen; Hubertus Fischer, Thomas Stocker, Michael Sigl and Matthias Bigler of The University of Bern [Universität Bern](CH); Mirko Severi and Rita Traversi of the The University of Florence [Università degli Studi di Firenze](IT) and Robert Mulvaney of the British Antarctic Survey in the UK.

    See the full article here .

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    Niels Bohr Institute Campus

    The Niels Bohr Institutet (DK) is a research institute of the Københavns Universitet [UCPH] (DK). The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the Københavns Universitet [UCPH] (DK), by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institutet (DK). Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.

    During the 1920s, and 1930s, the Institute was the centre of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institutet (DK).

    Københavns Universitet (UCPH) (DK) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge (UK), Yale University , The Australian National University (AU), and University of California-Berkeley , amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient.

    U Copenhagen campus

    The University of Copenhagen [Københavns Universitet] (DK)] is a public research university in Copenhagen, Denmark. Founded in 1479, the University of Copenhagen is the second-oldest university in Scandinavia, and ranks as one of the top universities in the Nordic countries and Europe.

    Its establishment sanctioned by Pope Sixtus IV, the University of Copenhagen was founded by Christian I of Denmark as a Catholic teaching institution with a predominantly theological focus. After 1537, it became a Lutheran seminary under King Christian III. Up until the 18th century, the university was primarily concerned with educating clergymen. Through various reforms in the 18th and 19th century, the University of Copenhagen was transformed into a modern, secular university, with science and the humanities replacing theology as the main subjects studied and taught.

    The University of Copenhagen consists of six different faculties, with teaching taking place in its four distinct campuses, all situated in Copenhagen. The university operates 36 different departments and 122 separate research centres in Copenhagen, as well as a number of museums and botanical gardens in and outside the Danish capital. The University of Copenhagen also owns and operates multiple research stations around Denmark, with two additional ones located in Greenland. Additionally, The Faculty of Health and Medical Sciences and the public hospitals of the Capital and Zealand Region of Denmark constitute the conglomerate Copenhagen University Hospital.

    A number of prominent scientific theories and schools of thought are namesakes of the University of Copenhagen. The famous Copenhagen Interpretation of quantum mechanics was conceived at the Niels Bohr Institute [Niels Bohr Institutet](DK), which is part of the university. The Department of Political Science birthed the Copenhagen School of Security Studies which is also named after the university. Others include the Copenhagen School of Theology and the Copenhagen School of Linguistics.

    As of October 2020, 39 Nobel laureates and 1 Turing Award laureate have been affiliated with the University of Copenhagen as students, alumni or faculty. Alumni include one president of the United Nations General Assembly and at least 24 prime ministers of Denmark. The University of Copenhagen fosters entrepreneurship, and between 5 and 6 start-ups are founded by students, alumni or faculty members each week.

    History

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge (UK), Yale University (US), The Australian National University (AU), and University of California, Berkeley(US), amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient.

    The University of Copenhagen was founded in 1479 and is the oldest university in Denmark. In 1474, Christian I of Denmark journeyed to Rome to visit Pope Sixtus IV, whom Christian I hoped to persuade into issuing a papal bull permitting the establishment of university in Denmark. Christian I failed to persuade the pope to issue the bull however and the king returned to Denmark the same year empty-handed. In 1475 Christian I’s wife Dorothea of Brandenburg Queen of Denmark made the same journey to Rome as her husband did a year before. Unlike Christian I Dorothea managed to persuade Pope Sixtus IV into issuing the papal bull. On the 19th of June, 1475 Pope Sixtus IV issued an official papal bull permitting the establishment of what was to become the University of Copenhagen.

    On the 4th of October, 1478 Christian I of Denmark issued a royal decree by which he officially established the University of Copenhagen. In this decree Christian I set down the rules and laws governing the university. The royal decree elected magistar Peder Albertsen as vice chancellor of the university and the task was his to employ various learned scholars at the new university and thereby establish its first four faculties: theology; law; medicine; and philosophy. The royal decree made the University of Copenhagen enjoy royal patronage from its very beginning. Furthermore, the university was explicitly established as an autonomous institution giving it a great degree of juridical freedom. As such the University of Copenhagen was to be administered without royal interference and it was not subject to the usual laws governing the Danish people.

    The University of Copenhagen was closed by the Church in 1531 to stop the spread of Protestantism and re-established in 1537 by King Christian III after the Lutheran Reformation and transformed into an evangelical-Lutheran seminary. Between 1675 and 1788 the university introduced the concept of degree examinations. An examination for theology was added in 1675 followed by law in 1736. By 1788 all faculties required an examination before they would issue a degree.

    In 1807 the British Bombardment of Copenhagen destroyed most of the university’s buildings. By 1836 however the new main building of the university was inaugurated amid extensive building that continued until the end of the century. The University Library (now a part of the Royal Library); the Zoological Museum; the Geological Museum; the Botanic Garden with greenhouses; and the Technical College were also established during this period.

    Between 1842 and 1850 the faculties at the university were restructured. Starting in 1842 the University Faculty of Medicine and the Academy of Surgeons merged to form the Faculty of Medical Science while in 1848 the Faculty of Law was reorganised and became the Faculty of Jurisprudence and Political Science. In 1850 the Faculty of Mathematics and Science was separated from the Faculty of Philosophy. In 1845 and 1862 Copenhagen co-hosted nordic student meetings with Lund University [Lunds universitet] (SE).

    The first female student was enrolled at the university in 1877. The university underwent explosive growth between 1960 and 1980. The number of students rose from around 6,000 in 1960 to about 26,000 in 1980 with a correspondingly large growth in the number of employees. Buildings built during this time period include the new Zoological Museum; the Hans Christian Ørsted and August Krogh Institutes; the campus centre on Amager Island; and the Panum Institute.

    The new university statute instituted in 1970 involved democratisation of the management of the university. It was modified in 1973 and subsequently applied to all higher education institutions in Denmark. The democratisation was later reversed with the 2003 university reforms. Further change in the structure of the university from 1990 to 1993 made a Bachelor’s degree programme mandatory in virtually all subjects.

    Also in 1993 the law departments broke off from the Faculty of Social Sciences to form a separate Faculty of Law. In 1994 the University of Copenhagen designated environmental studies; north–south relations; and biotechnology as areas of special priority according to its new long-term plan. Starting in 1996 and continuing to the present the university planned new buildings including for the University of Copenhagen Faculty of Humanities at Amager (Ørestaden) along with a Biotechnology Centre. By 1999 the student population had grown to exceed 35,000 resulting in the university appointing additional professors and other personnel.

    In 2003 the revised Danish university law removed faculty staff and students from the university decision process creating a top-down control structure that has been described as absolute monarchy since leaders are granted extensive powers while being appointed exclusively by higher levels in the organization.

    In 2005 the Center for Health and Society (Center for Sundhed og Samfund – CSS) opened in central Copenhagen housing the Faculty of Social Sciences and Institute of Public Health which until then had been located in various places throughout the city. In May 2006 the university announced further plans to leave many of its old buildings in the inner city of Copenhagen- an area that has been home to the university for more than 500 years. The purpose of this has been to gather the university’s many departments and faculties on three larger campuses in order to create a bigger more concentrated and modern student environment with better teaching facilities as well as to save money on rent and maintenance of the old buildings. The concentration of facilities on larger campuses also allows for more inter-disciplinary cooperation. For example the Departments of Political Science and Sociology are now located in the same facilities at CSS and can pool resources more easily.

    In January 2007 the University of Copenhagen merged with the Royal Veterinary and Agricultural University and the Danish University of Pharmaceutical Science. The two universities were converted into faculties under the University of Copenhagen and were renamed as the Faculty of Life Sciences and the Faculty of Pharmaceutical Sciences. In January 2012 the Faculty of Pharmaceutical Sciences and the veterinary third of the Faculty of Life Sciences merged with the Faculty of Health Sciences forming the Faculty of Health and Medical Sciences and the other two thirds of the Faculty of Life Sciences were merged into the Faculty of Science.

    Cooperative agreements with other universities

    The university cooperates with universities around the world. In January 2006, the University of Copenhagen entered into a partnership of ten top universities, along with the Australian National University (AU), Swiss Federal Institute of Technology in Zürich [ETH Zürich] [Eidgenössische Technische Hochschule Zürich](CH), The National University of Singapore [Universiti Nasional Singapura] (SG), Peking University [北京大学](CN), University of California Berkeley (US), University of Cambridge (UK), University of Oxford (UK), University of Tokyo {東京大学](JP) and Yale University (US). The partnership is referred to as the International Alliance of Research Universities (IARU).

    The Department of Scandinavian Studies and Linguistics at University of Copenhagen signed a cooperation agreement with the Danish Royal School of Library and Information Science in 2009.

     
  • richardmitnick 12:06 pm on March 3, 2022 Permalink | Reply
    Tags: "Confessions of a former fireball-How Earth became habitable", , , Eventually the scientists settled on a bold proposition: Early Earth was covered with rocks that do not currently exist on Earth., Magnesium-rich minerals react with carbon dioxide to produce carbonates thereby playing a key role in sequestering atmospheric carbon., Paleogeology, Somehow a massive amount of atmospheric carbon had to be removed., , The effect would be similar to a rare type of modern deep-sea thermal vent called the "Lost City" hydrothermal field located in the Atlantic Ocean., The researchers said the rate of atmospheric carbon sequestration would have been more than 10 times faster than would be possible with a mantle of modern-day rocks., The researchers suggest that as the molten Earth started to solidify its hydrated wet mantle—the planet's 3000-kilometer-thick rocky layer—convected vigorously., The scientists combined aspects of thermodynamics; fluid mechanics and atmospheric physics to build their model., These 'weird' rocks on the early Earth would readily react with seawater to generate a large flux of hydrogen which is widely believed to be essential for the creation of biomolecules., These rocks would have been enriched in a mineral called pyroxene. More importantly they were extremely enriched in magnesium.,   

    From Yale University (US) and The California Institute of Technology (US): “Confessions of a former fireball-How Earth became habitable” 

    From Yale University (US)

    and

    Caltech Logo

    The California Institute of Technology (US)

    Fred Mamoun
    fred.mamoun@yale.edu
    203-436-2643

    Jim Shelton

    1
    Credit: Simone Marchi, Southwest Research Institute

    Researchers at Yale and Caltech have a bold new theory to explain how Earth transformed itself from a fiery, carbon-clouded ball of rocks into a planet capable of sustaining life.

    The theory covers Earth’s earliest years and involves “weird” rocks that interacted with seawater in just the right way to nudge biological matter into existence.

    “This period is the most enigmatic time in Earth history,” said Jun Korenaga, a professor of Earth and planetary sciences at Yale and co-author of a new study in the journal Nature. “We’re presenting the most complete theory, by far, for Earth’s first 500 million years.”

    The study’s first author is Yoshinori Miyazaki, a former Yale graduate student who is now a Stanback Postdoctoral Fellow at Caltech. The study is based on the final chapter of Miyazaki’s Yale dissertation.

    Most scientists believe that Earth began with an atmosphere much like that of the planet Venus. Its skies were filled with carbon dioxide—more than 100,000 times the current level of atmospheric carbon—and Earth’s surface temperature would have exceeded 400 degrees Fahrenheit.

    Biological life would have been unable to form, much less survive under such conditions, scientists agree.

    “Somehow a massive amount of atmospheric carbon had to be removed,” Miyazaki said. “Because there is no rock record preserved from the early Earth, we set out to build a theoretical model for the very early Earth from scratch.”

    Miyazaki and Korenaga combined aspects of thermodynamics, fluid mechanics, and atmospheric physics to build their model. Eventually they settled on a bold proposition: Early Earth was covered with rocks that do not currently exist on Earth.

    “These rocks would have been enriched in a mineral called pyroxene, and they likely had a dark greenish color,” Miyazaki said. “More importantly they were extremely enriched in magnesium, with a concentration level seldom observed in present-day rocks.”

    Miyazaki said magnesium-rich minerals react with carbon dioxide to produce carbonates thereby playing a key role in sequestering atmospheric carbon.

    The researchers suggest that as the molten Earth started to solidify its hydrated wet mantle—the planet’s 3000-kilometer-thick rocky layer—convected vigorously. The combination of a wet mantle and high-magnesium pyroxenites dramatically sped up the process of pulling CO2 out of the atmosphere.

    In fact, the researchers said the rate of atmospheric carbon sequestration would have been more than 10 times faster than would be possible with a mantle of modern-day rocks, requiring a mere 160 million years.

    “As an added bonus, these ‘weird’ rocks on the early Earth would readily react with seawater to generate a large flux of hydrogen, which is widely believed to be essential for the creation of biomolecules,” Korenaga said.

    The effect would be similar to a rare type of modern deep-sea thermal vent called the “Lost City” hydrothermal field located in the Atlantic Ocean. The Lost City hydrothermal field’s abiotic production of hydrogen and methane has made it a prime location for investigating the origin of life on Earth.

    “Our theory has the potential to address not just how Earth became habitable, but also why life emerged on it,” Korenaga added.

    See the full article here .

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    Caltech campus

    The The California Institute of Technology (US) is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration (US)’s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute(US) as well as National Aeronautics and Space Administration(US). According to a 2015 Pomona College(US) study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration(US); National Science Foundation(US); Department of Health and Human Services(US); Department of Defense(US), and Department of Energy(US).

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech (US), The California Institute of Technology also operates the Caltech Palomar Observatory(US); the Owens Valley Radio Observatory(US);the Caltech Submillimeter Observatory(US); the W. M. Keck Observatory at the Mauna Kea Observatory(US); the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Richland, Washington; and Kerckhoff Marine Laboratory(US) in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center(US), part of the Infrared Processing and Analysis Center(US) located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles(US) to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network(US) stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

    Yale University (US) is a private Ivy League research university in New Haven, Connecticut. Founded in 1701 as the Collegiate School, it is the third-oldest institution of higher education in the United States and one of the nine Colonial Colleges chartered before the American Revolution. The Collegiate School was renamed Yale College in 1718 to honor the school’s largest private benefactor for the first century of its existence, Elihu Yale. Yale University is consistently ranked as one of the top universities and is considered one of the most prestigious in the nation.

    Chartered by Connecticut Colony, the Collegiate School was established in 1701 by clergy to educate Congregational ministers before moving to New Haven in 1716. Originally restricted to theology and sacred languages, the curriculum began to incorporate humanities and sciences by the time of the American Revolution. In the 19th century, the college expanded into graduate and professional instruction, awarding the first PhD in the United States in 1861 and organizing as a university in 1887. Yale’s faculty and student populations grew after 1890 with rapid expansion of the physical campus and scientific research.

    Yale is organized into fourteen constituent schools: the original undergraduate college, the Yale Graduate School of Arts and Sciences and twelve professional schools. While the university is governed by the Yale Corporation, each school’s faculty oversees its curriculum and degree programs. In addition to a central campus in downtown New Haven, the university owns athletic facilities in western New Haven, a campus in West Haven, Connecticut, and forests and nature preserves throughout New England. As of June 2020, the university’s endowment was valued at $31.1 billion, the second largest of any educational institution. The Yale University Library, serving all constituent schools, holds more than 15 million volumes and is the third-largest academic library in the United States. Students compete in intercollegiate sports as the Yale Bulldogs in the NCAA Division I – Ivy League.

    As of October 2020, 65 Nobel laureates, five Fields Medalists, four Abel Prize laureates, and three Turing award winners have been affiliated with Yale University. In addition, Yale has graduated many notable alumni, including five U.S. Presidents, 19 U.S. Supreme Court Justices, 31 living billionaires, and many heads of state. Hundreds of members of Congress and many U.S. diplomats, 78 MacArthur Fellows, 252 Rhodes Scholars, 123 Marshall Scholars, and nine Mitchell Scholars have been affiliated with the university.

    Research

    Yale is a member of the Association of American Universities (AAU) (US) and is classified among “R1: Doctoral Universities – Very high research activity”. According to the National Science Foundation (US), Yale spent $990 million on research and development in 2018, ranking it 15th in the nation.

    Yale’s faculty include 61 members of the National Academy of Sciences (US), 7 members of the National Academy of Engineering (US) and 49 members of the American Academy of Arts and Sciences (US). The college is, after normalization for institution size, the tenth-largest baccalaureate source of doctoral degree recipients in the United States, and the largest such source within the Ivy League.

    Yale’s English and Comparative Literature departments were part of the New Criticism movement. Of the New Critics, Robert Penn Warren, W.K. Wimsatt, and Cleanth Brooks were all Yale faculty. Later, the Yale Comparative literature department became a center of American deconstruction. Jacques Derrida, the father of deconstruction, taught at the Department of Comparative Literature from the late seventies to mid-1980s. Several other Yale faculty members were also associated with deconstruction, forming the so-called “Yale School”. These included Paul de Man who taught in the Departments of Comparative Literature and French, J. Hillis Miller, Geoffrey Hartman (both taught in the Departments of English and Comparative Literature), and Harold Bloom (English), whose theoretical position was always somewhat specific, and who ultimately took a very different path from the rest of this group. Yale’s history department has also originated important intellectual trends. Historians C. Vann Woodward and David Brion Davis are credited with beginning in the 1960s and 1970s an important stream of southern historians; likewise, David Montgomery, a labor historian, advised many of the current generation of labor historians in the country. Yale’s Music School and Department fostered the growth of Music Theory in the latter half of the 20th century. The Journal of Music Theory was founded there in 1957; Allen Forte and David Lewin were influential teachers and scholars.

    In addition to eminent faculty members, Yale research relies heavily on the presence of roughly 1200 Postdocs from various national and international origin working in the multiple laboratories in the sciences, social sciences, humanities, and professional schools of the university. The university progressively recognized this working force with the recent creation of the Office for Postdoctoral Affairs and the Yale Postdoctoral Association.

    Notable alumni

    Over its history, Yale has produced many distinguished alumni in a variety of fields, ranging from the public to private sector. According to 2020 data, around 71% of undergraduates join the workforce, while the next largest majority of 16.6% go on to attend graduate or professional schools. Yale graduates have been recipients of 252 Rhodes Scholarships, 123 Marshall Scholarships, 67 Truman Scholarships, 21 Churchill Scholarships, and 9 Mitchell Scholarships. The university is also the second largest producer of Fulbright Scholars, with a total of 1,199 in its history and has produced 89 MacArthur Fellows. The U.S. Department of State Bureau of Educational and Cultural Affairs ranked Yale fifth among research institutions producing the most 2020–2021 Fulbright Scholars. Additionally, 31 living billionaires are Yale alumni.

    At Yale, one of the most popular undergraduate majors among Juniors and Seniors is political science, with many students going on to serve careers in government and politics. Former presidents who attended Yale for undergrad include William Howard Taft, George H. W. Bush, and George W. Bush while former presidents Gerald Ford and Bill Clinton attended Yale Law School. Former vice-president and influential antebellum era politician John C. Calhoun also graduated from Yale. Former world leaders include Italian prime minister Mario Monti, Turkish prime minister Tansu Çiller, Mexican president Ernesto Zedillo, German president Karl Carstens, Philippine president José Paciano Laurel, Latvian president Valdis Zatlers, Taiwanese premier Jiang Yi-huah, and Malawian president Peter Mutharika, among others. Prominent royals who graduated are Crown Princess Victoria of Sweden, and Olympia Bonaparte, Princess Napoléon.

    Yale alumni have had considerable presence in U.S. government in all three branches. On the U.S. Supreme Court, 19 justices have been Yale alumni, including current Associate Justices Sonia Sotomayor, Samuel Alito, Clarence Thomas, and Brett Kavanaugh. Numerous Yale alumni have been U.S. Senators, including current Senators Michael Bennet, Richard Blumenthal, Cory Booker, Sherrod Brown, Chris Coons, Amy Klobuchar, Ben Sasse, and Sheldon Whitehouse. Current and former cabinet members include Secretaries of State John Kerry, Hillary Clinton, Cyrus Vance, and Dean Acheson; U.S. Secretaries of the Treasury Oliver Wolcott, Robert Rubin, Nicholas F. Brady, Steven Mnuchin, and Janet Yellen; U.S. Attorneys General Nicholas Katzenbach, John Ashcroft, and Edward H. Levi; and many others. Peace Corps founder and American diplomat Sargent Shriver and public official and urban planner Robert Moses are Yale alumni.

    Yale has produced numerous award-winning authors and influential writers, like Nobel Prize in Literature laureate Sinclair Lewis and Pulitzer Prize winners Stephen Vincent Benét, Thornton Wilder, Doug Wright, and David McCullough. Academy Award winning actors, actresses, and directors include Jodie Foster, Paul Newman, Meryl Streep, Elia Kazan, George Roy Hill, Lupita Nyong’o, Oliver Stone, and Frances McDormand. Alumni from Yale have also made notable contributions to both music and the arts. Leading American composer from the 20th century Charles Ives, Broadway composer Cole Porter, Grammy award winner David Lang, and award-winning jazz pianist and composer Vijay Iyer all hail from Yale. Hugo Boss Prize winner Matthew Barney, famed American sculptor Richard Serra, President Barack Obama presidential portrait painter Kehinde Wiley, MacArthur Fellow and contemporary artist Sarah Sze, Pulitzer Prize winning cartoonist Garry Trudeau, and National Medal of Arts photorealist painter Chuck Close all graduated from Yale. Additional alumni include architect and Presidential Medal of Freedom winner Maya Lin, Pritzker Prize winner Norman Foster, and Gateway Arch designer Eero Saarinen. Journalists and pundits include Dick Cavett, Chris Cuomo, Anderson Cooper, William F. Buckley, Jr., and Fareed Zakaria.

    In business, Yale has had numerous alumni and former students go on to become founders of influential business, like William Boeing (Boeing, United Airlines), Briton Hadden and Henry Luce (Time Magazine), Stephen A. Schwarzman (Blackstone Group), Frederick W. Smith (FedEx), Juan Trippe (Pan Am), Harold Stanley (Morgan Stanley), Bing Gordon (Electronic Arts), and Ben Silbermann (Pinterest). Other business people from Yale include former chairman and CEO of Sears Holdings Edward Lampert, former Time Warner president Jeffrey Bewkes, former PepsiCo chairperson and CEO Indra Nooyi, sports agent Donald Dell, and investor/philanthropist Sir John Templeton,

    Yale alumni distinguished in academia include literary critic and historian Henry Louis Gates, economists Irving Fischer, Mahbub ul Haq, and Nobel Prize laureate Paul Krugman; Nobel Prize in Physics laureates Ernest Lawrence and Murray Gell-Mann; Fields Medalist John G. Thompson; Human Genome Project leader and National Institutes of Health (US) director Francis S. Collins; brain surgery pioneer Harvey Cushing; pioneering computer scientist Grace Hopper; influential mathematician and chemist Josiah Willard Gibbs; National Women’s Hall of Fame inductee and biochemist Florence B. Seibert; Turing Award recipient Ron Rivest; inventors Samuel F.B. Morse and Eli Whitney; Nobel Prize in Chemistry laureate John B. Goodenough; lexicographer Noah Webster; and theologians Jonathan Edwards and Reinhold Niebuhr.

    In the sporting arena, Yale alumni include baseball players Ron Darling and Craig Breslow and baseball executives Theo Epstein and George Weiss; football players Calvin Hill, Gary Fenick, Amos Alonzo Stagg, and “the Father of American Football” Walter Camp; ice hockey players Chris Higgins and Olympian Helen Resor; Olympic figure skaters Sarah Hughes and Nathan Chen; nine-time U.S. Squash men’s champion Julian Illingworth; Olympic swimmer Don Schollander; Olympic rowers Josh West and Rusty Wailes; Olympic sailor Stuart McNay; Olympic runner Frank Shorter; and others.

     
  • richardmitnick 11:12 pm on February 28, 2022 Permalink | Reply
    Tags: "A Slow-Motion Section of the San Andreas Fault May Not Be So Harmless After All", , , , , , Paleogeology, ,   

    From Columbia University (US) – State of the Planet: “A Slow-Motion Section of the San Andreas Fault May Not Be So Harmless After All” 

    From Columbia University (US) – State of the Planet

    at

    Columbia U bloc
    Columbia University (US)

    February 28, 2022
    Kevin Krajick

    Where Big Quakes Were Thought Unlikely, Deep-Down Rocks Say Otherwise

    Most people have heard about the San Andreas Fault. It’s the 800-mile-long monster that cleaves California from south to north, as two tectonic plates slowly grind against each other, threatening to produce big earthquakes.

    Lesser known is the fact that the San Andreas comprises three major sections that can move independently. In all three, the plates are trying to move past each other in opposing directions, like two hands rubbing against each other. In the southern and the northern sections, the plates are locked much of the time—stuck together in a dangerous, immobile embrace. This causes stresses to build over years, decades or centuries. Finally a breaking point comes; the two sides lurch past each other violently, and there is an earthquake. However in the central section, which separates the other two, the plates slip past each other at a pleasant, steady 26 millimeters or so each year. This prevents stresses from building, and there are no big quakes. This is called aseismic creep.

    1
    California’s San Andreas Fault. The “creeping” central section, subject of a new study, is in yellow. Rock samples from almost 2 miles down were taken at the San Andreas Fault Observatory at Depth, or SAFOD, marked by the red star. (Adapted from Coffey et al., Geology, 2022)

    At least that is the story most scientists have been telling so far. Now, a study of rocks drilled from nearly 2 miles under the surface suggests that the central section has hosted many major earthquakes, including some that could have been fairly recent. The study, which uses new chemical-analysis methods to gauge the heating of rocks during prehistoric quakes, just appeared in the online edition of the journal Geology.

    “This means we can get larger earthquakes on the central section than we thought,” said lead author Genevieve Coffey, who did the research as a graduate student at Columbia University’s Lamont-Doherty Earth Observatory. “We should be aware that there is this potential, that it is not always just continuous creep.”

    he threats of the San Andreas are legion. The northern section hosted the catastrophic 1906 San Francisco magnitude 7.9 earthquake, which killed 3,000 people and leveled much of the city. Also, the 1989 M6.9 Loma Prieta quake, which killed more than 60 and collapsed a major elevated freeway. The southern section caused the 1994 M6.7 Northridge earthquake near Los Angeles, also killing about 60 people. Many scientists believe it is building energy for a 1906-scale event.

    The central section, by contrast, appears harmless. Only one small area, near its southern terminus, is known to produce any real quakes. There, magnitude 6 events—not that dangerous by most standards—occur about every 20 years. Because of their regularity, scientists hoping to study clues that might signal a coming quake have set up a major observatory atop the fault near the city of Parkfield. It features a 3.2-kilometer-deep borehole from which rock cores have been retrieved, and monitoring instruments above and below ground. It was rock from near the bottom of the borehole that Coffey and her colleagues analyzed.

    3
    The San Andreas Fault, on the Carrizo Plain, about 100 miles from Los Angeles. (NASA Jet Propulsion Laboratory)

    When earthquake faults slip, friction along the moving parts can cause temperatures to spike hundreds of degrees above those of surrounding rocks. This cooks the rocks, altering the makeup of organic compounds in any sedimentary formations along the fault path. Recently, study coauthors Pratigya Polissar and Heather Savage figured out how to take advantage of these so-called biomarkers, using the altered compositions to map prehistoric earthquakes.They say that by calculating the degree of heating in the rock, they can spot past events and estimate how far the fault moved; from this, they can roughly extrapolate the sizes of resulting earthquakes. At Lamont-Doherty, they refined the method in the U.S. Northeast, Alaska, and off Japan.

    In the new study, the researchers found many such altered compositions in a band of highly disturbed sedimentary rock lying between 3192 and 3196 meters below the surface. In all, they say the blackish, crumbly stuff shows signs of more than 100 quakes. In most, the fault appears to have jumped more than 1.5 meters (5 feet). This would translate to at least a magnitude 6.9 quake, the size of the destructive Loma Prieta and Northridge events. But many could well have been larger, say the researchers, because their method of estimating earthquake magnitude is still evolving. They say quakes along the central section may have been similar to other large San Andreas events, including the one that destroyed San Francisco.

    The current official California earthquake hazard model, used to set building codes and insurance rates, does include the remote possibility of a big central-section rupture. But inclusion of this possibility, arrived at through mathematical calculations, was controversial, given the lack of evidence for any such prior event. The new study appears to be the first to indicate that such quakes have in fact occurred here. The authors say they could have originated in the central section, or perhaps more likely, started to the north or south, and migrated through the central.
    ===
    So, when did these quakes happen? Trenches dug by paleoseismologists across the central section have revealed no disturbed soil layers that would indicate quakes rupturing the surface in the last 2,000 years—about the limit for detection using that method in this region. But 2,000 years is an eye blink in geologic terms. And, the excavations could be missing any number of quakes that might not necessarily have ruptured the surface at specific sites.

    The researchers used a second new technique to address this question. The biomarkers run along very narrow bands, from microscopic to just a couple of centimeters wide. Just a few inches or feet away, the rock heats only enough to drive out some or all of the gas argon naturally present there. Conveniently for the authors, other scientists have long used the ratio of radioactive potassium to argon, into which potassium slowly decays, to measure the ages of rocks. The more argon compared to potassium, the older the rock. Thus, if some or all of the argon is driven out by quake-induced heat, the radioactive “clock” gets reset, and the rock appears younger than identical nearby rock that was not heated.

    This is exactly what the team found. The sediments they studied were formed tens of millions of years ago in an ancient Pacific basin that was subducted under California. Yet the ages of rocks surrounding the thin quake slip zones came out looking as young as 3.2 million years by the potassium-argon clock. This sets out a time frame, but only a vague one, because the scientists still do not know how to judge the amount of argon that was driven out, and thus how thoroughly the clock may have been reset. This means that 3.2 million years is just an upper age limit for the most recent quakes, said Coffey; in fact, some could have taken place as little as a few hundred or a few thousand years ago, she said. The group is now working on a new project to refine the age interpretations.

    “Ultimately, our work points to the potential for higher magnitude earthquakes in central California and highlights the importance of including the central [San Andreas Fault] and other creeping faults in seismic hazard analysis,” the authors write.

    William Ellsworth, a geophysicist at Stanford University who has led research at the drill site, pointed out that while a possible big quake is included in the state’s official hazard assessment, “Most earthquake scientists think that they happen rarely, as tectonic strain is not accumulating at significant rates, if at all, along it at the present time,” he said.

    Morgan Page, a seismologist with the U.S. Geological Survey who coauthored the hazard assessment, said the study breaks new ground. “The creeping section is a difficult place to do paleoseismology, because evidence for earthquakes can be easily erased by the creep,” she said. “If this holds up, this is the first evidence of a big seismic rupture in this part of the fault.” She said that if a big earthquake can tear through the creeping section, it means that it is possible—though chances would be remote—that one could start at the very southern tip of the San Andreas, travel through the central section and continue all the way on up to the end of the northern section—the so-called “Big One” that people like to speculate about. “I’m excited about this new evidence, and hope we can use it to better constrain this part of our model,” she said.

    How much should this worry Californians? “People should not be alarmed,” said Lamont-Doherty geologist and study coauthor Stephen Cox. “Building codes in California are now quite good. Seismic events are inevitable. Work like this helps us figure out what is the biggest possible event, and helps everyone prepare.”

    The study’s other coauthors are Sidney Hemming and Gisela Winckler of Lamont-Doherty, and Kelly Bradbury of Utah State University. Genevieve Coffey is now at New Zealand’s GNS Science; Pratigya Polissar and Heather Savage are now at the University of California- Santa Cruz.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Earth Institute is a research institute at Columbia University that was established in 1995. Its stated mission is to address complex issues facing the planet and its inhabitants, with a focus on sustainable development. With an interdisciplinary approach, this includes research in climate change, geology, global health, economics, management, agriculture, ecosystems, urbanization, energy, hazards, and water. The Earth Institute’s activities are guided by the idea that science and technological tools that already exist could be applied to greatly improve conditions for the world’s poor, while preserving the natural systems that support life on Earth.

    The Earth Institute supports pioneering projects in the biological, engineering, social, and health sciences, while actively encouraging interdisciplinary projects—often combining natural and social sciences—in pursuit of solutions to real world problems and a sustainable planet. In its work, the Earth Institute remains mindful of the staggering disparities between rich and poor nations, and the tremendous impact that global-scale problems—such as the HIV/AIDS pandemic, climate change and extreme poverty—have on all nations.

    Columbia U Campus

    Columbia University (US) was founded in 1754 as King’s College by royal charter of King George II of England. It is the oldest institution of higher learning in the state of New York and the fifth oldest in the United States.

    University Mission Statement

    Columbia University is one of the world’s most important centers of research and at the same time a distinctive and distinguished learning environment for undergraduates and graduate students in many scholarly and professional fields. The University recognizes the importance of its location in New York City and seeks to link its research and teaching to the vast resources of a great metropolis. It seeks to attract a diverse and international faculty and student body, to support research and teaching on global issues, and to create academic relationships with many countries and regions. It expects all areas of the University to advance knowledge and learning at the highest level and to convey the products of its efforts to the world.

    Columbia University is a private Ivy League research university in New York City. Established in 1754 on the grounds of Trinity Church in Manhattan Columbia is the oldest institution of higher education in New York and the fifth-oldest institution of higher learning in the United States. It is one of nine colonial colleges founded prior to the Declaration of Independence, seven of which belong to the Ivy League. Columbia is ranked among the top universities in the world by major education publications.

    Columbia was established as King’s College by royal charter from King George II of Great Britain in reaction to the founding of Princeton College. It was renamed Columbia College in 1784 following the American Revolution, and in 1787 was placed under a private board of trustees headed by former students Alexander Hamilton and John Jay. In 1896, the campus was moved to its current location in Morningside Heights and renamed Columbia University.

    Columbia scientists and scholars have played an important role in scientific breakthroughs including brain-computer interface; the laser and maser; nuclear magnetic resonance; the first nuclear pile; the first nuclear fission reaction in the Americas; the first evidence for plate tectonics and continental drift; and much of the initial research and planning for the Manhattan Project during World War II. Columbia is organized into twenty schools, including four undergraduate schools and 15 graduate schools. The university’s research efforts include the Lamont–Doherty Earth Observatory, the Goddard Institute for Space Studies, and accelerator laboratories with major technology firms such as IBM. Columbia is a founding member of the Association of American Universities and was the first school in the United States to grant the M.D. degree. With over 14 million volumes, Columbia University Library is the third largest private research library in the United States.

    The university’s endowment stands at $11.26 billion in 2020, among the largest of any academic institution. As of October 2020, Columbia’s alumni, faculty, and staff have included: five Founding Fathers of the United States—among them a co-author of the United States Constitution and a co-author of the Declaration of Independence; three U.S. presidents; 29 foreign heads of state; ten justices of the United States Supreme Court, one of whom currently serves; 96 Nobel laureates; five Fields Medalists; 122 National Academy of Sciences members; 53 living billionaires; eleven Olympic medalists; 33 Academy Award winners; and 125 Pulitzer Prize recipients.

     
  • richardmitnick 2:52 pm on February 22, 2022 Permalink | Reply
    Tags: "A Forgotten Continent From 40 Million Years Ago May Have Just Been Rediscovered", , Balkanatolia, , , , Paleogeology,   

    From CNRS-The National Center for Scientific Research [Centre national de la recherche scientifique] (FR) via Science Alert (AU): “A Forgotten Continent From 40 Million Years Ago May Have Just Been Rediscovered” 

    From CNRS-The National Center for Scientific Research [Centre national de la recherche scientifique] (FR)

    via

    ScienceAlert

    Science Alert (AU)

    22 FEBRUARY 2022
    CLARE WATSON

    1
    Balkanatolia. Credit: Alexis Licht, Grégoire Métais/CNRS.

    A low-lying continent that existed some 40 million years ago and was home to exotic fauna may have “paved the way” for Asian mammals to colonize southern Europe, new research suggests.

    Wedged between Europe, Africa and Asia, this forgotten continent – which researchers have dubbed “Balkanatolia” – became a gateway between Asia and Europe when sea levels dropped and a land bridge formed, around 34 million years ago.

    “When and how the first wave of Asian mammals made it to south-eastern Europe remains poorly understood,” palaeogeologist Alexis Licht and colleagues write in their new study [Earth-Science Reviews].

    But the result was nothing short of dramatic. Around 34 million years ago, at the end of the Eocene epoch, huge numbers of native mammals disappeared from Western Europe as new Asian mammals emerged, in a sudden extinction event now known as the Grande Coupure.

    Recent fossil findings in the Balkans, however, have upended that timeline, pointing towards a ‘peculiar’ bioregion that appears to have enabled Asian mammals to colonize southeastern Europe as much as 5 to 10 million years before the Grande Coupure occurred.

    To investigate, Licht, of the French National Centre for Scientific Research, and colleagues re-examined the evidence from all known fossil sites in the area, which covers the present-day Balkan peninsula and Anatolia, the westernmost protrusion of Asia.

    The age of these sites was revised based on current geological data, and the team reconstructed paleogeographic changes that transpired in the region, which has a “complex history of episodic drowning and re-emergence”.

    What they found suggests Balkanatolia served as a stepping stone for animals to move from Asia into western Europe, with the transformation of the ancient landmass from standalone continent to land bridge – and subsequent invasion with Asian mammals – coinciding with some “dramatic paleogeographic changes”.

    2
    Balkanatolia, 40 million years ago, and at the present day. Credit: Alexis Licht, Grégoire Métais/CNRS.

    Around 50 million years ago, Balkanatolia was an isolated archipelago, separate from the neighboring continents, where a unique collection of animals distinct from those of Europe and eastern Asia thrived, the analysis found.

    Then a combination of falling sea levels, growing Antarctic ice sheets and tectonic shifts connected the Balkanatolia continent to Western Europe, between 40 to 34 million years ago.

    This allowed Asian mammals including rodents and four-legged hoofed mammals (aka ungulates) to adventure westward and invade Balkanatolia, the fossil record shows.

    Adding to that record, Licht and colleagues also discovered fragments of a jawbone belonging to a rhinoceros-like animal at a new fossil site in Turkey, which they dated to around 38 to 35 million years ago.

    3
    Upper molar of an Asian Brontothere mammal. Credit: Alexis Licht, Grégoire Métais/CNRS.

    The fossil is, arguably, the oldest Asian-like ungulate discovered in Anatolia to date and predates the Grande Coupure by at least 1.5 million years, suggesting that Asian mammals were well on their way to Europe via Balkanatolia.

    This southern pathway to Europe across Balkanatolia was perhaps more favorable for adventurous animals than traversing higher-latitude routes through Central Asia which at the time were drier, cooler, desert steppes, Licht and colleagues also suggest.

    However, they point out in their paper that the “past connectivity between individual Balkanatolian islands and the existence of this southern dispersal route remain debated”, and that the story pieced together thus far “is only built on mammalian fossils and a more complete picture of past Balkanatolian biodiversity remains to be drawn”.

    Many of the geological changes that gave rise to Balkanatolia have yet to be fully understood, and it’s important to note that this review is just one team’s interpretation of the fossil record.

    That said, the fossil record of mammals and other vertebrates living on islands is usually sparse and patchy, whereas the rich terrestrial fossil record of Balkanatolia “provides a unique opportunity to document the evolution and demise of island biotas in deep time,” the team concludes.

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    CNRS-The National Center for Scientific Research [Centre national de la recherche scientifique](FR) is the French state research organisation and is the largest fundamental science agency in Europe.

    In 2016, it employed 31,637 staff, including 11,137 tenured researchers, 13,415 engineers and technical staff, and 7,085 contractual workers. It is headquartered in Paris and has administrative offices in Brussels; Beijing; Tokyo; Singapore; Washington D.C.; Bonn; Moscow; Tunis; Johannesburg; Santiago de Chile; Israel; and New Delhi.

    The CNRS was ranked No. 3 in 2015 and No. 4 in 2017 by the Nature Index, which measures the largest contributors to papers published in 82 leading journals.

    The CNRS operates on the basis of research units, which are of two kinds: “proper units” (UPRs) are operated solely by the CNRS, and “joint units” (UMRs – French: Unité mixte de recherche)[9] are run in association with other institutions, such as universities or INSERM. Members of joint research units may be either CNRS researchers or university employees (maîtres de conférences or professeurs). Each research unit has a numeric code attached and is typically headed by a university professor or a CNRS research director. A research unit may be subdivided into research groups (“équipes”). The CNRS also has support units, which may, for instance, supply administrative, computing, library, or engineering services.

    In 2016, the CNRS had 952 joint research units, 32 proper research units, 135 service units, and 36 international units.

    The CNRS is divided into 10 national institutes:

    Institute of Chemistry (INC)
    Institute of Ecology and Environment (INEE)
    Institute of Physics (INP)
    Institute of Nuclear and Particle Physics (IN2P3)
    Institute of Biological Sciences (INSB)
    Institute for Humanities and Social Sciences (INSHS)
    Institute for Computer Sciences (INS2I)
    Institute for Engineering and Systems Sciences (INSIS)
    Institute for Mathematical Sciences (INSMI)
    Institute for Earth Sciences and Astronomy (INSU)

    The National Committee for Scientific Research, which is in charge of the recruitment and evaluation of researchers, is divided into 47 sections (e.g. section 41 is mathematics, section 7 is computer science and control, and so on).Research groups are affiliated with one primary institute and an optional secondary institute; the researchers themselves belong to one section. For administrative purposes, the CNRS is divided into 18 regional divisions (including four for the Paris region).

    Some selected CNRS laboratories

    APC laboratory
    Centre d’Immunologie de Marseille-Luminy
    Centre d’Etude Spatiale des Rayonnements
    Centre européen de calcul atomique et moléculaire
    Centre de Recherche et de Documentation sur l’Océanie
    CINTRA (joint research lab)
    Institut de l’information scientifique et technique
    Institut de recherche en informatique et systèmes aléatoires
    Institut d’astrophysique de Paris
    Institut de biologie moléculaire et cellulaire
    Institut Jean Nicod
    Laboratoire de Phonétique et Phonologie
    Laboratoire d’Informatique, de Robotique et de Microélectronique de Montpellier
    Laboratory for Analysis and Architecture of Systems
    Laboratoire d’Informatique de Paris 6
    Laboratoire d’informatique pour la mécanique et les sciences de l’ingénieur
    Observatoire océanologique de Banyuls-sur-Mer
    SOLEIL
    Mistrals

     
  • richardmitnick 1:08 pm on February 22, 2022 Permalink | Reply
    Tags: "Updating Dating Helps Tackle Deep-Time Quandaries", , , Cyanobacteria likely played a key role in dramatically altering Earth’s atmosphere during the Great Oxidation Event between about 2.4 billion and 2.0 billion years ago., , , Evidence for single-celled life exists as far back as the Archean eon., , , , , Paleogeology, Scientists study Precambrian sedimentary rocks that have long endured the travails of tectonics and attempted erasure by erosion., Scientists tell time in the geologic record by measuring radioactive elements stored in rocks., The stage was set for the evolution of eukaryotes—organisms that encase DNA within their cellular nuclei—which eventually began to breathe oxygen and grow into bigger organisms.   

    From Eos: “Updating Dating Helps Tackle Deep-Time Quandaries” 

    From AGU
    Eos news bloc

    From Eos

    22 February 2022
    Alka Tripathy-Lang

    Geochronologists are finding fresh approaches to familiar methodologies, especially by zapping rocks with lasers to tackle classic Precambrian problems.

    1
    The archipelago of Svalbard, located in the Arctic Ocean north of Norway, includes the approximately 6-kilometer-thick Neoproterozoic to early Phanerozoic Hecla Hoek succession, shown in part here at Claravågen, on the island of Nordaustlandet. Many of the Precambrian parts of this sedimentary succession, including those shown in this image captured by drone, await radiometric age constraints. Credit: Marjorie Cantine.

    During the immense span of time that was the Precambrian—the first 88% of Earth’s 4.6-billion-year history—the planet witnessed milestone events like the dawn of life, the atmosphere’s oxygenation, and global glaciations that helped shape the world in which humanity exists today.

    To better understand such momentous processes, scientists study Precambrian sedimentary rocks that have long endured the travails of tectonics and attempted erasure by erosion. For example, they study marine shales and limestones that record the chemistry of the water column. Because gases dissolved in seawater and those in the atmosphere interact where air meets sea, understanding the geochemistry in Precambrian marine shales and limestones lets scientists tease out clues about bygone climes.

    The unique swings in geochemistry observed in Precambrian rocks are much larger in magnitude than those that occurred in more recent and familiar periods in Earth’s history, said Alan Rooney, an Earth and planetary sciences professor at Yale University. The sedimentary strata also host evidence of the evolution of complex life, from single-celled organisms to multicellular eukaryotes. “Biologically, a lot is going on” in these rocks, he said.

    However, to understand cause and effect when studying a Precambrian rock, “you need to know how old it is,” said Kaarel Mänd, a research fellow at the University of Tartu in Estonia. “Otherwise, you cannot place it in the sequence of events.”

    To this end, geochronologists—scientists who tell time in the geologic record by measuring radioactive elements stored in rocks—are now applying innovative instruments to rejuvenate isotopic dating systems that had fallen out of fashion because of their often cumbersome analytical requirements, including large sample sizes and arduous preparation and measurement. In particular, these advances help geochronologists rapidly collect data for isochron diagrams, which first revolutionized the field more than 60 years ago by providing a way to determine the ages of otherwise inscrutable ancient rocks.

    Precambrian Predicaments

    Evidence for single-celled life exists as far back as the Archean eon. But the evolution of a specific type of single-celled life-cyanobacteria-likely played a key role in dramatically altering Earth’s atmosphere during the Great Oxidation Event between about 2.4 billion and 2.0 billion years ago. During this time, the atmospheric chemistry at Earth’s surface shifted from reducing conditions, in which oxygen is rapidly consumed, to oxidizing conditions replete with the gas. The Great Oxidation Event is “perhaps the most conspicuous big event that happened in the Precambrian,” said Mänd.

    This long-term process set the stage for the evolution of eukaryotes—organisms that encase DNA within their cellular nuclei—which eventually began to breathe oxygen and grow into bigger organisms, said Annie Bauer, an assistant professor of geoscience at the University of Wisconsin–Madison. Whether this happened roughly simultaneously across the globe or in geographically isolated pockets at different times is still being studied. By comparing the timing of oxygenation from place to place, she said, scientists can determine whether these first whiffs arose together as a globally synchronous exhalation or as discrete puffs.

    Later, from about 1.8 billion to 0.8 billion years ago, atmospheric oxygen levels flattened out and stabilized, leading some scientists to dub this time the “boring billion.” Yet multicellular life emerged during this time; important ores like copper, iron, lead, and zinc—sensitive to the amount of oxygen near them—were deposited; and continents such as ancient North America grew as supercontinents assembled.

    The remainder of the geochemistry tucked into the Precambrian’s rock record features evidence of unusual climate dynamics perhaps related to Earth’s carbon cycle, said Marjorie Cantine, a postdoctoral fellow at Goethe University Frankfurt in Germany. Understanding the Earth system changes that might have led to the flowering of diverse, complex life during the Phanerozoic—the present geological eon—requires dating the rocks that hold these clues, she said.

    The Phanerozoic “[has] this really rich fossil record that you can use to tell time,” said Cantine. In contrast, Precambrian life was not mineralized. The biostratigraphy that helps geologists sort through time in the Phanerozoic is largely unavailable in Precambrian rocks, she said.

    Scientists who delve into Precambrian rocks often rely on the physical position of different rocks in relation to one another to tell their relative ages, said Mänd. Once-molten magma, for instance, will always be younger than any sedimentary rock it cuts across. For that reason, dating that crosscutting igneous rock provides a minimum age for the sedimentary strata, although the sedimentary rock could still be many millions of years older than that minimum age, he explained.

    Even in cases where scientists have tried to directly date marine Precambrian rocks, for example, they sometimes know the rocks’ ages only to within hundreds of millions of years, said Nick Roberts, a research scientist at the British Geological Survey.

    Mathematical Tricks for Dating Rocks

    Since Marie Curie first coined the term “radioactivity” in the late 1800s, the field of radiometric dating of rocks—geochronology—has emerged and matured.

    Naturally occurring elements have different isotopes, in which the number of protons is the same but the number of neutrons varies, resulting in different masses of the same element. For some elements, certain isotopes are radiogenic, meaning they exist because of radioactive decay. Geochronology focuses on measuring the decay of a radioactive “parent” isotope to a radiogenic “daughter” one, like the decay of certain isotopes of uranium to lead or rubidium to strontium. “We know pretty well how quickly that happens,” said Cantine. By measuring parent-daughter ratios in a rock or mineral, scientists can calculate when the dated material came into existence. “We’re able to do that extraordinarily well in certain special minerals” that form with parent isotopes but without any daughter products, she said.

    One of those special minerals is zircon. A hardy mineral made from zirconium, silicon, and oxygen, zircon crystals can retain their initial geochemical signatures despite being bathed in magma or doused in water. Crucially for geochronologists, zircon crystals readily incorporate uranium as they form—when the clock starts, so to speak—but they do not initially incorporate daughter isotopes of lead. Any lead found in zircon today, said Cantine, is there solely because of radioactive decay over time.

    Measuring uranium and lead in zircons can sometimes help geochronologists when they’re able to find these time capsules. For example, layers of ash belched by volcanoes often contain zircons that effectively date the time of eruption. Such layers can provide markers in successions of marine rocks, which often lack any other indicator of time. Modern laboratory techniques enable the development of very high precision dates from zircon crystals, making it so that finding zircon-bearing ashes is the dream scenario for Precambrian geologists. Unfortunately, volcanic ashes do not occur everywhere Earth scientists seek geochronology on sedimentary rocks, said Cantine. In another approach, geochronologists date many tens, or even hundreds, of zircons extracted from sandstones. Known as detrital zircons, these minerals initially formed in other rocks that were then eroded and redeposited—sometimes multiple times—before arriving at their terminal sedimentary destination. Detrital zircons can help fingerprint the source regions of the sands in a sandstone and provide a maximum age constraint for the rock, said Bauer, but they can’t tell you the actual time at which the rock formed. Recent research used a high number of detrital zircons dated at low precision using quick laser methods and then dated the youngest of those grains with more time-consuming high-precision methods. Although this process can sometimes get close to the formation age, it will still be a maximum age.

    Luckily, geochronologists have several other radiometric systems at their disposal to directly date marine sedimentary rocks like shales and carbonates. Unfortunately, as shales and carbonates form, they incorporate various radiogenic daughter products in addition to parent isotopes, meaning a single measurement is likely to yield an erroneously old age for a rock.

    To overcome such limitations, though, “we’re able to do some mathematical tricks by measuring multiple different locations within the same rock,” said Cantine.

    The ultimate trick is the isochron method, first conceived in 1961, which requires no knowledge of how much radiogenic daughter isotope a sample incorporated at the time it formed. A “device of magnificent power and simplicity,” wrote Brent Dalrymple in The Age of the Earth in 1991, “an isochron is a line of equal time.” Obtained by analyzing several minerals from the same rock or several rocks that formed together but that contain different amounts of the parent element, the simplest form of an isochron requires measurement of only a parent, its radiogenic daughter product, and a third quantity—the relative amount of a nonradiogenic isotope of the daughter element, which should remain constant over the lifetime of a sample. The inherent assumption, said Cantine, is that the rocks or minerals in question began with the same amount of all isotopes of the daughter, regardless of whether they were produced by radioactive decay, and that no later process has perturbed that balance.

    By dividing both the amount of the parent and the amount of the radiogenic daughter by the amount of that third quantity—a nonradiogenic daughter isotope—and then plotting the resulting values on the x and y axes, respectively, wrote Dalrymple, “the points will fall on a line whose slope is a function of the age of the rock.” In other words, simple division allows geochronologists to exploit the equation of a line.

    Resuscitating an Old Method

    Continental rocks exposed to water and weather at Earth’s surface deteriorate into smaller bits, including clay minerals, through physical and chemical erosion. When these flecks of former rocks end up in the seas, they eventually form layers of fine-grained sedimentary rocks called shales. That’s how shales have formed for more than 3 billion years, Mänd said.

    Often rich in organic matter, these thinly layered rocks often form in deep ocean waters. One way to date shales as old as about 2.5 billion years, said Rooney, is by using the decay of a radiogenic isotope of rhenium, a metal, to another metal, osmium. But the process of isolating rhenium from osmium is arduous, involving several days of complicated laboratory work. Dates developed through such arduous research are playing increasingly important roles in telling time in ancient sedimentary rocks lacking zircon-bearing ashes.

    When rhenium decays to osmium, it does so via a process called beta decay, in which an atom loses or gains a proton (i.e., the daughter becomes a different element) but has the same mass as the parent (i.e., the two have the same combined total number of protons and neutrons). This process holds true for any beta decay system, including rubidium’s transformation to strontium, said Mikael Tillberg, a postdoctoral fellow at Linnaeus University and the University of Gothenburg, both in Sweden. The isochron method was first demonstrated using the rubidium-strontium dating system, but other methods that often proved faster or cheaper to employ partially supplanted its use. As such, said Tillberg, rubidium-strontium dating is often viewed as antiquated. However, innovative technologies are reinvigorating this vintage timepiece that can constrain the finicky ages of those fine-grained shales.

    Laser ablation systems let geochronologists shoot holes on the scale of tens of micrometers in target materials, said Tillberg, dramatically reducing the sample size needed per measurement. The laser ablates the target rock, turning it into an aerosol that is immediately piped to a mass spectrometer.

    Because the parent and daughter isotopes used in rubidium-strontium geochronology have the same mass, attempting to measure them simultaneously in an instrument designed to measure different masses may seem counterintuitive. A triple quadrupole mass spectrometer solves this quandary, said Tillberg. (A quadrupole in this context consists of four parallel rods, with each opposing pair having a different voltage that attracts or repels charged particles.)

    When ablated, aerosolized rock enters the instrument, and a plasma ionizes it into charged particles. Then, the first quadrupole separates the particles according to mass, explained Tillberg. The next quadrupole contains a gas like nitrous oxide, which donates oxygen to strontium but not to rubidium. The strontium, now combined with oxygen, has a higher mass that is easily separated from rubidium by the third quadrupole, he said. This potent combination of laser ablation and triple quadrupole mass spectrometry allows both isotopes to be measured from the same imperceptibly small slug of sample while eliminating the complicated and time-consuming laboratory work needed to dissolve a rock and physically separate parent and daughter isotopes.

    “Honing into a single layer in the rock record…especially if samples come from drill cores that already have small sample sizes,” becomes much simpler with this updated method, said Darwinaji Subarkah, a doctoral student at the University of Adelaide in Australia. Because the measurement process is so fast, multiple spots from a single sliver of sample can be ablated and analyzed in hours, generating the data necessary for an isochron, he said. Furthermore, whereas traditional rubidium-strontium methods consume entire samples, laser ablation preserves the sample, leaving the measured rock available for future reference, said Subarkah. Moreover, because laser ablation requires much smaller amounts of material, additional sample is often available for analysis by other methods.

    However, to generate a robust isochron, the analyzed parts of a rock must be texturally equivalent. “You need to be able to assume that your initial strontium composition of all the [sample] was the same,” said Bauer. “That’s what makes sedimentary rocks really tricky.”

    Careful petrographic characterization, especially at the nanoscale, can potentially solve this problem, helping to differentiate among clays that came from eroding continents, clays that grew as the sediment became a rock, and clays that changed as the rock warmed and recrystallized, said Subarkah. By combining petrographic analyses with laser ablation, he said, “we’re actually looking at individual relationships between the different mineral phases.”

    Carbonate Conundrums

    Phanerozoic carbonate rocks—limestones and dolomites—are “often completely composed of these big pieces of fossil [animals] stuck together,” Mänd said, which helps tell time.

    But carbonates exist from more than 3 billion years ago, well into the Precambrian, when they were “completely built, as far as we know, by microbes,” according to Cantine.

    Sedimentary carbonates can be dated using uranium’s decay to lead. But carbonates don’t incorporate much uranium, and they tend to include lead as they form, said Cantine. “That means that we have problems on both the parent and the daughter side.” A variation on the simple isochron, along with lasers, has rejuvenated uranium-lead dating for carbonates.

    The first attempt at uranium-lead carbonate geochronology began in the 1980s, said Roberts, and continued through the late 1990s with studies of Precambrian rocks, mostly. Early papers describe methods that involved drilling carbonate rock samples, dissolving chunks with acids, chemically separating the uranium and lead, and making measurements on a thermal ionization mass spectrometer (TIMS) instrument, Roberts explained. This required big samples, a lot of time in the lab, and expensive equipment. However, carbonates are notoriously complicated at relatively small spatial scales, and by dissolving a large piece for analysis, any variations of uranium or lead within individual crystals or across the sample are lost as they are averaged into a single data point, he said.

    Because geochronologists can focus their lasers to zap rocks at a scale of tens of micrometers, many measurements can be obtained rapidly from a single sample, allowing researchers to observe small-scale variations. These previously inscrutable variations provide the spread in measurements needed for a good isochron, said Roberts. Although individual measurements obtained by laser ablation come with higher uncertainties than data collected by traditional methods, the sheer number of measurements made possible by using lasers means that isochron-determined ages also can be precise.

    Carbonates “are wonderfully sensitive to the environment around them,” said Cantine. Carbonate rocks can record temporally distinct processes, such as the initial deposition or precipitation of carbonate, its transformation into rock, any subsequent deformation by burial or tectonic processes, and even uplift from the ocean floor to the tops of mountains. Within a single sample, she said, “you could potentially have multiple meaningful ages preserved.” Because these different processes often leave behind texturally distinct carbonates visible only under the microscope, combining petrographic examination with laser ablation techniques is critical for connecting a date to a specific geological process, she said.

    Nevertheless, just because we have lasers doesn’t mean it’s time to leave the old methods in the past. TIMS measurements in particular are highly precise, said Cantine. In her work, she’s aiming for the best of both worlds, she said, by rapidly assessing carbonate dates using laser ablation and then following up with TIMS analyses to confirm the results.

    What Came First?

    By precisely dating sedimentary rocks with updated geochronologic techniques, said Mänd, scientists can begin to solve some long-standing chicken-and-egg problems in Precambrian geology. For example, snowball Earth glacial events recorded in sedimentary rocks that happened about 2.4 billion and 0.6 billion years ago coincide with both atmospheric oxygen fluctuations and peculiarly large swings in Earth’s carbon chemistry.

    The older snowball Earth event (the Huronian glaciations) may have been triggered by excess oxygen produced by cyanobacteria. But the widely accepted age constraints for this event come from 2.45-billion-year-old Archean rock that sits below the sedimentary rocks recording the past global freezes, along with a 2.22-billion-year-old crosscutting igneous intrusion into the sedimentary rocks, leaving a span of nearly 300 million years, said Bauer. With better time constraints, scientists parse just how many glaciations occurred, whether they were truly global, and what their relationship is to the cyanobacteria-fueled oxygen spike and the carbon swings recorded in these rocks, she explained.

    During and after the younger snowball Earth events during the Cryogenian period, Earth’s earliest animals evolved amid continued episodic glaciations and more curious carbon records. But as in the Huronian, the relations and timing of these glaciations, carbon fluctuations, and evolution of life are unclear. Understanding the time component with the help of the best available geochronologic systems and instrumentation, said Cantine, “is critical for figuring out how and in what ways these events might be connected.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    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 9:02 am on February 18, 2022 Permalink | Reply
    Tags: "Tilting of Earth’s crust governed the flow of ancient megafloods", , , , Paleogeology,   

    From The University of California-Santa Cruz (US): “Tilting of Earth’s crust governed the flow of ancient megafloods” 

    From The University of California-Santa Cruz (US)

    February 14, 2022
    Tim Stephens
    stephens@ucsc.edu

    Study provides new perspective on Washington state’s Channeled Scablands, carved by the Missoula megafloods at the end of the last ice age

    1
    Enormous volumes of floodwater from the Missoula megafloods once poured over Dry Falls, which stretches 3.5 miles wide and drops 400 feet to a plunge pool now fed by groundwater. Photo by Tamara Pico.

    2
    Towering cliffs carved by the Missoula megafloods are found throughout the Channeled Scablands in eastern Washington. Photo by Tamara Pico.

    3
    The landforms on the Columbia Plateau in eastern Washington reveal a past punctuated by violent floods. Credit: NASA Earth Observatory.

    As ice sheets began melting at the end of the last ice age, a series of cataclysmic floods called the Missoula megafloods scoured the landscape of eastern Washington, carving long, deep channels and towering cliffs through an area now known as the Channeled Scablands. They were among the largest known floods in Earth’s history, and geologists struggling to reconstruct them have now identified a crucial factor governing their flows.

    In a study published February 14 in PNAS, researchers showed how the changing weight of the ice sheets would have caused the entire landscape to tilt, changing the course of the megafloods.

    “People have been looking at high water marks and trying to reconstruct the size of these floods, but all of the estimates are based on looking at the present-day topography,” said lead author Tamara Pico, assistant professor of Earth and planetary sciences at UC Santa Cruz. “This paper shows that the ice age topography would have been different over broad scales due to the deformation of Earth’s crust by the weight of the ice sheets.”

    During the height of the last ice age, vast ice sheets covered much of North America. They began to melt after about 20,000 years ago, and the Missoula megafloods occurred between 18,000 and 15,500 years ago. Pico’s team studied how the changing weight of the ice sheets during this period would have tilted the topography of eastern Washington, changing how much water would flow into different channels during the floods.

    Glacial outburst floods

    Glacial Lake Missoula formed in western Montana when a lobe of the Cordilleran ice sheet dammed the Clark Fork valley in the Idaho panhandle and melt water built up behind the dam. Eventually the water got so deep that the ice dam began to float, resulting in a glacial outburst flood. After enough water had been released, the ice dam resettled and the lake refilled. This process is thought to have been repeated dozens of times over a period of several thousand years.

    Downstream from glacial Lake Missoula, the Columbia River was dammed by another ice lobe, forming glacial Lake Columbia. When Lake Missoula’s outburst floods poured into Lake Columbia, the water spilled over to the south onto the eastern Washington plateau, eroding the landscape and creating the Channeled Scablands.

    During this period, the deformation of the Earth’s crust in response to the growing and shrinking of ice sheets would have changed the elevation of the topography by hundreds of meters, Pico said. Her team incorporated these changes into flood models to investigate how the tilting of the landscape would have changed the routing of the megafloods and their erosional power in different channels.

    “We used flood models to predict the velocity of the water and the erosional power in each channel, and compared that to what would be needed to erode basalt, the type of rock on that landscape,” Pico said.

    They focused on two major channel systems, the Cheney-Palouse and Telford-Crab Creek tracts. Their results showed that earlier floods would have eroded both tracts, but that in later floods the flow would have been concentrated in the Telford-Crab Creek system.

    “As the landscape tilted, it affected both where the water overflowed out of Lake Columbia and how water flowed in the channels, but the most important effect was on the spillover into those two tracts,” Pico said. “What’s intriguing is that the topography isn’t static, so we can’t just look at the topography of today to reconstruct the past.”

    The findings provide a new perspective on this fascinating landscape, she said. Steep canyons hundreds of feet deep, dry falls, and giant potholes and ripple marks are among the many remarkable features etched into the landscape by the massive floods.

    “When you are there in person, it’s crazy to think about the scale of the floods needed to carve those canyons, which are now dry,” Pico said. “There are also huge dry waterfalls—it’s a very striking landscape.”

    She also noted that the oral histories of Native American tribes in this region include references to massive floods. “Scientists were not the first people to look at this,” Pico said. “People may even have been there to witness these floods.”

    In addition to Pico, the coauthors include Scott David at Utah State University; Isaac Larsen and Karin Lehnigk at the University of Massachusetts-Amherst; Alan Mix at Oregon State University; and Michael Lamb at the California Institute of Technology. This work was supported by the National Science Foundation.

    See the full article here.


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Santa Cruz (US) campus.

    The University of California-Santa Cruz (US) , opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    UCO Lick Observatory’s 36-inch Great Refractor telescope housed in the South (large) Dome of main building.

    UC Santa Cruz (US) Lick Observatory Since 1888 Mt Hamilton, in San Jose, California, Altitude 1,283 m (4,209 ft)

    UC Observatories Lick Automated Planet Finder fully robotic 2.4-meter optical telescope at Lick Observatory, situated on the summit of Mount Hamilton, east of San Jose, California, USA.

    The UCO Lick C. Donald Shane telescope is a 120-inch (3.0-meter) reflecting telescope located at the Lick Observatory, Mt Hamilton, in San Jose, California, Altitude 1,283 m (4,209 ft).

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch.)
    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    Shelley Wright of UC San Diego with (US) NIROSETI, developed at U Toronto Dunlap Institute for Astronomy and Astrophysics (CA) at the 1-meter Nickel Telescope at Lick Observatory at UC Santa Cruz
    NIROSETI team from left to right Rem Stone UCO Lick Observatory Dan Werthimer, UC Berkeley; Jérôme Maire, U Toronto; Shelley Wright, UCSD; Patrick Dorval, U Toronto; Richard Treffers, Starman Systems. (Image by Laurie Hatch).

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by University of California-Berkeley (US) researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    Frank Drake with his Drake Equation. Credit Frank Drake.

    Drake Equation, Frank Drake, Seti Institute (US).

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

     
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