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  • richardmitnick 1:50 pm on February 23, 2020 Permalink | Reply
    Tags: "Where is the greatest risk to our mineral resource supplies?", , , , Geology, , USGS-US Geological Survey   

    From the United States Geological Survey (USGS) via phys.org: “Where is the greatest risk to our mineral resource supplies?” 

    From the United States Geological Survey (USGS)

    via


    phys.org

    February 21, 2020
    Alex Demas, United States Geological Survey

    1
    Bastnaesite (the reddish parts) in Carbonatite. Bastnaesite is an important ore for rare earth elements, one of the mineral commodities identified as most at-risk of supply disruption by the USGS in a new methodology. Credit: Scott Horvath, USGS

    Policymakers and the U.S. manufacturing sector now have a powerful tool to help them identify which mineral commodities they rely on that are most at risk to supply disruptions, thanks to a new methodology by the U.S. Geological Survey and its partners.

    “This methodology is an important part of how we’re meeting our goals in the President Trump’s Strategy to ensure a reliable supply of critical minerals,” said USGS director Jim Reilly. “It provides information supporting American manufacturers’ planning and sound supply-chain management decisions.”

    The methodology evaluated the global supply of and U.S. demand for 52 mineral commodities for the years 2007 to 2016. It identified 23 mineral commodities, including some rare earth elements, cobalt, niobium and tungsten, as posing the greatest supply risk for the U.S. manufacturing sector. These commodities are vital for mobile devices, renewable energy, aerospace and defense applications, among others.

    “Manufacturers of new and emerging technologies depend on mineral commodities that are currently sourced largely from other countries,” said USGS scientist Nedal Nassar, lead author of the methodology. “It’s important to understand which commodities pose the greatest risks for which industries within the manufacturing sector.”

    The supply risk of mineral commodities to U.S. manufacturers is greatest under the following three circumstances: U.S. manufacturers rely primarily on foreign countries for the commodities, the countries in question might be unable or unwilling to continue to supply U.S. manufacturers with the minerals; and U.S. manufacturers are less able to handle a price shock or from a disruption in supply.

    3
    A graph showing the net import reliance of the United States for more than 90 different mineral commodities. Credit: USGS

    “Supply chains can be interrupted for any number of reasons,” said Nassar. “International trade tensions and conflict are well-known reasons, but there are many other possibilities. Disease outbreaks, natural disasters, and even domestic civil strife can affect a country’s mineral industry and its ability to export mineral commodities to the U.S.”

    Risk is not set in stone; it changes based on global market conditions that are specific to each individual mineral commodity and to the industries that use them. However, the analysis indicates that risk typically does not change drastically over short periods, but instead remains relatively constant or changes steadily.

    “One thing that struck us as we were evaluating the results was how consistent the mineral commodities with the highest risk of supply disruption have been over the past decade,” said Nassar. “This is important for policymakers and industries whose plans extend beyond year-to-year changes.”

    For instance, between 2007 and 2016, the risk for rare earth elements peaked in 2011 and 2012 when China halted exports during a dispute with Japan. However, the supply of rare earth elements consistently remained among the highest risk commodities throughout the entire study period.

    In 2019, the U.S. Department of Commerce, in coordination with the Department of the Interior and other federal agencies, published the interagency report entitled “A Federal Strategy to Ensure a Reliable Supply of Critical Minerals,” in response to President Trump’s Executive Order 13817. Among other things, the strategy commits the U.S. Department of the Interior to improve the geophysical, geologic, and topographic mapping of the U.S.; make the resulting data and metadata electronically accessible; support private mineral exploration of critical minerals; make recommendations to streamline permitting and review processes enhancing access to critical mineral resources.

    The methodology is entitled “Evaluating the Mineral Commodity Supply Risk of the U.S. Manufacturing Sector,” and is published in Science Advances.

    See the full article here .

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    About Science X in 100 words

    Science X™ is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004 (Physorg.com), Science X’s readership has grown steadily to include 5 million scientists, researchers, and engineers every month. Science X publishes approximately 200 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Science X community members enjoy access to many personalized features such as social networking, a personal home page set-up, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.
    Mission 12 reasons for reading daily news on Science X Organization Key editors and writersinclude 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

    Created by an act of Congress in 1879, the U.S. Geological Survey has evolved over the ensuing 125 years, matching its talent and knowledge to the progress of science and technology. The USGS is the sole science agency for the Department of the Interior. It is sought out by thousands of partners and customers for its natural science expertise and its vast earth and biological data holdings.

    On March 3, 1879, we were established by the passing of the Organic Act through Congress. Our main responsibilities were to map public lands, examine geological structure, and evaluate mineral resources. Over the next century, our mission expanded to include the research of groundwater, ecosystems, environmental health, natural hazards, and climate and land use change.

     
  • richardmitnick 10:08 am on February 21, 2020 Permalink | Reply
    Tags: "'Glacial Earthquakes' Spotted for the First Time on Thwaites", , , , Geology, That’s bad news scientists agree because Thwaites helps hold back the West Antarctic Ice Sheet from flowing into the sea., Thwaites is responsible for about 4% of global sea level rise., Thwaites’s floating ice shelf is degrading.   

    From Eos: “‘Glacial Earthquakes’ Spotted for the First Time on Thwaites” 

    From AGU
    Eos news bloc

    From Eos

    17 February 2020
    Katherine Kornei
    hobbies4kk@gmail.com

    These seismic events, triggered by icebergs capsizing and ramming into Thwaites, reveal that the glacier has lost some of its floating ice shelf.

    1
    Icebergs calving off Thwaites Glacier occasionally capsize and launch seismic waves that travel hundreds of kilometers. Credit: David Vaughan, British Antarctic Survey.

    Icebergs calve off glaciers all the time. But most don’t pitch backward, capsize, and send seismic waves radiating out for thousands of kilometers.

    New research reports that such “glacial earthquakes” have now been detected for the first time on Antarctica’s Thwaites Glacier. These observations confirm that Thwaites’s floating ice shelf is degrading. That’s bad news, scientists agree, because the glacier helps hold back the West Antarctic Ice Sheet from flowing into the sea.

    Flipping Icebergs

    2
    Scenarios for iceberg calving at fast tidewater glaciers. Buoyancy-driven calving is likely to produce icebergs with small width-to-height ratios that will capsize against the terminus front. The generated iceberg-to-terminus contact force is responsible for the production of glacial earthquakes. Credit: Sergeant et al., 2019, Annals of Geology

    Thwaites Glacier, roughly the size of the state of Florida, is one of the largest sources of ice loss in Antarctica and is responsible for about 4% of global sea level rise.

    It regularly sheds icebergs hundreds of meters on a side into the Amundsen Sea, but some of these chunks of ice aren’t just drifting away, said J. Paul Winberry, a geophysicist at Central Washington University in Ellensburg who led the new study. Thanks to their shape, they’re capsizing. “They’re taller than they are wide. They’re top-heavy, and they want to flip over,” said Winberry.

    Over several tens of seconds, these icebergs roll backward and collide with the new edge of Thwaites. “They bang the front of the glacier,” said Winberry.

    Those collisions launch seismic waves that can be picked up by detectors hundreds and even thousands of kilometers away. Last year, Winberry was combing through seismic data and serendipitously discovered two of these collisions. “We got really lucky,” said Winberry.

    By triangulating the signals recorded by seven seismic stations spread across West Antarctica, he and his colleagues determined that the events had occurred on the front of Thwaites.

    Using optical and radar satellite imagery acquired within minutes of the seismic events, both of which took place 8 November 2018, the team confirmed that calving had indeed occurred. The researchers counted five capsized icebergs, their icy undersides now exposed. (In radar imagery, such icebergs appear dark—ice reflects radio waves more poorly than snow.)

    Seismology complements satellite imagery when it comes to studying glaciers, said Lucas Zoet, a glaciologist at the University of Wisconsin–Madison not involved in the research. Satellites can obtain high-resolution imagery but typically pass over the same spot on Earth only every few days or, at best, every few hours, Zoet said. Seismological instruments, on the other hand, are always listening. That’s important, he said, because “the real interesting part might happen in just a couple minutes.”

    All About Ice Shelves

    These glacial earthquakes shed light on Thwaites’s geometry and therefore its future stability.

    For icebergs to capsize, they must be taller than they are wide. That’s common in Greenland [Annals of Geology above] because most glaciers there don’t contain floating ice shelves, said Winberry. “The edge of a glacier is grounded or close to touching the bedrock.” That ice thickness translates into icebergs being taller than they are wide, which renders them unstable in the water.


    But Antarctic glaciers tend to have floating ice shelves, so their iceberg progeny are typically wider than they are tall and, accordingly, don’t produce glacial earthquakes. Thwaites appears to be an anomaly.

    “This portion of Thwaites Glacier is distinct from the rest of Antarctica in that it’s lost most of its floating ice shelf,” said Winberry. “We think that’s what’s going to happen to the rest of Thwaites going forward.” Ice shelves, by literally getting hung up on islands and underwater ridges, help stabilize glaciers by acting like buttresses.

    Tiny Temblors, Too

    The seismological data that Winberry and his colleagues analyzed revealed more than just two glacial earthquakes—there were also over 600 tiny temblors in the 6 days leading up to the calving.

    “We think we’re hearing the accelerating failure of the ice before it calves off,” said Winberry.

    That’s an important window into how Thwaites is changing, he said. These observations can be used to inform models of calving, Winberry and his colleagues suggest.

    These results were published last month in Geophysical Research Letters.

    In the future, Winberry and his team plan to do a more systematic search for glacial earthquakes on Thwaites. They’re interested in determining possible triggering events that might drive calving, like big storms or moving sea ice.

    See the full article here .

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

     
  • richardmitnick 3:17 pm on February 20, 2020 Permalink | Reply
    Tags: "Victoria’s volcanic history confirms the state’s Aboriginal inhabitation before 34000 years", , Budj Bim Australian World Heritage property., Geology, ,   

    From University of Melbourne: “Victoria’s volcanic history confirms the state’s Aboriginal inhabitation before 34,000 years” 

    u-melbourne-bloc

    From University of Melbourne

    19 February 2020
    Dr Erin Matchan
    Professor David Phillips

    9
    Lake Surprise at Budj Bim, as it is today. (cafuego/Flickr/CC BY-SA 2.0)

    8
    Eugene von Guerard’s Tower Hill, 1855.

    New techniques for dating volcanic eruptions, a lone axe and Indigenous oral traditions give us a new minimum age for human occupation in Victoria.

    The questions of when people first arrived in Australia and the nature of their dispersal across the continent are subjects of ongoing debate.

    A lack of ceramic artefacts and permanent structures has resulted in an apparent scarcity of dateable archaeological sites older than about 10,000 years, yet what evidence there is suggests occupation across much of the continent for 30,000 or more years.

    1
    Budj Bim is the only Australian World Heritage property listed exclusively for its Aboriginal cultural values. Picture: AAP

    In western Victoria, the Budj Bim Cultural Landscape World Heritage Site in Victoria contains the world’s oldest known aquaculture system, built by the Gunditjmara People more than 6,000 years ago, near a volcano called the Budj Bim Volcanic Complex.

    3
    Crater of Mount Eccles (Victoria). Flickr: Crater of Mount Eccles (Victoria)

    4
    The Budj Bim Cultural Landcape was inscribed on the World Heritage List on 6 July 2019. https://www.environment.gov.au

    However, the Gunditjmara have lived in this area for much longer than this, and now, using a new volcanic activity dating technique and matching this with physical archaeological evidence and the rich oral traditions of the Gunditjmara people we have confirmed human habitation in this region at least 34,000 years ago [GeoScience World-Geology].

    Existing evidence for the oldest known human habitations in Australia comes largely from radiocarbon (¹⁴C) dating of charcoal, and optically stimulated luminescence (OSL) dating of quartz grains in rock shelter sediments.

    In southeastern Australia, only six sites (located in what are now Tasmania, New South Wales, and South Australia) older than 30,000 years are considered definitively dated by ¹⁴C and/or OSL methods, with ages spanning 37,000 – 50,000 years.

    There is a need for independent age constraints to test some of the more controversial ages and add to the sparse age record.

    The oral traditions of Australian Aboriginal peoples have enabled perpetuation of ecological knowledge across many generations, providing a valuable resource of archaeological information.

    Some surviving traditions appear to reference geological events such as volcanic eruptions, earthquakes, and meteorite impacts, and it has been proposed that some of these traditions may have been transmitted for thousands of years.

    Examples include oral traditions around the 7,000 year old Kinrara volcano in north Queensland [Quaternary Geochronology], and a number of oral traditions implying much lower sea levels than present day and dramatic differences in vegetation reflecting cooler climates that existed thousands of years ago.

    3
    Schematic map showing the location of recent lavas and confirmed >30,000 year-old occupation sites in south-eastern Australia. Picture: Supplied/Modified from Allen & O’Connell, 2014.

    The plains of western Victoria and south eastern South Australia are punctuated by a number of conspicuous small hills and remarkably circular lakes.

    These striking features are the remnants of volcanoes that are geologically very young. While the more than 400 individual volcanoes are considered to be extinct, the volcanic province of which they are a part, the Newer Volcanic Province, is regarded as active.

    This region includes the youngest volcanoes in Australia, Mount Gambier and Mount Schank, both around 5,000 years old.

    Although precise ages remain elusive, a number of other volcanoes in the Newer Volcanic Province are thought to have erupted within the last 100,000 years, and the people living in this region tens of thousands of years ago would no doubt have witnessed volcanic activity.

    However, in Australia, little archaeological evidence has been found beneath volcanic ash deposits and lava flows – perhaps because very few studies have looked for this.

    A single stone artefact, the ‘Bushfield axe’, was serendipitously discovered in the 1940s during sinking of a post hole through a sequence of finely layered volcanic ash from the Tower Hill Volcanic Complex, about 40 kilometres southeast of the Budj Bim Volcanic Complex (formerly Mount Eccles).

    This ash from Tower Hill has not previously been dated.

    4
    The age of Tower Hill, associated as it is with the Bushfield axe, represents the minimum age for human presence in Victoria. Picture: Mertie/Flickr

    The only previous estimation of the eruption age is from a combined OSL and ¹⁴C dating study of sediments above and below the volcanic ash, which gave an age of 35,000 ± 3,000 years.

    However, that study did not consider the archaeological implications of this age, probably because the existence of the Bushfield axe is not widely known.

    Previous ages for the Budj Bim Volcanic Complex are variable, largely derived from ¹⁴C dating of sediments in the crater lake (Lake Surprise) and swamps that formed after the lava modified the regional drainage system.

    The oldest of these swamp sediment ages, ~31,400 ± 400 years, represents a minimum age for eruption of the Budj Bim Volcanic Complex.

    This is consistent with ages of 33,600 ± 5,200 years and 39,600 ± 7,000 years determined by lava surface exposure dating methods, but the precise eruption age was not definitively known until now.

    Another dating technique, called argon-argon (or ⁴⁰Ar/³⁹Ar dating) has been used to date much older volcanoes, including nearby Mount Rouse (284,400 +/- 1,800 years.

    Technological improvements over the last decade, including work in our lab at the University of Melbourne’s School of Earth Sciences, have firmly established that ⁴⁰Ar/³⁹Ar dating, which relies on the rate of natural radioactive decay of potassium into argon in minerals, can be successfully applied to archaeological timescales.

    5
    Schematic geological map showing the location of volcanoes in the study area and the ⁴⁰Ar/³⁹Ar sampling locations. Picture: Supplied.

    In our study, published in the journal Geology, in collaboration with Professor Fred Jourdan and Dr Korien Oostingh at Curtin University, we applied the ⁴⁰Ar/³⁹Ar dating technique to a ‘lava bomb’ from the Tower Hill eruption sequence and to a sample from the Tyrendarra lava flow, the biggest lava flow from the Budj Bim Volcanic Complex.

    This study was supported by a University of Melbourne McCoy Seed Fund grant with Museum Victoria and an ARC Discovery Grant.

    These analyses produced lava eruption ages of 36,800 ± 3,800 ka for Tower Hill and 36,900 ± 3,100 for the Budj Bim Volcanic Complex.

    These ages fall within the range of ¹⁴C and OSL ages reported for the six earliest known occupation sites in southeastern Australia. The age of Tower Hill, associated as it is with the Bushfield axe, represents the minimum age for human presence in Victoria.

    And if oral traditions surrounding Budj Bim do indeed reference volcanic activity, this could mean that these are some of the longest-lived oral traditions in the world.

    See the full article here .


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    u-melbourne-campus

    The University of Melbourne (informally Melbourne University) is an Australian public research university located in Melbourne, Victoria. Founded in 1853, it is Australia’s second oldest university and the oldest in Victoria. Times Higher Education ranks Melbourne as 33rd in the world, while the Academic Ranking of World Universities places Melbourne 44th in the world (both first in Australia).

    Melbourne’s main campus is located in Parkville, an inner suburb north of the Melbourne central business district, with several other campuses located across Victoria. Melbourne is a sandstone university and a member of the Group of Eight, Universitas 21 and the Association of Pacific Rim Universities. Since 1872 various residential colleges have become affiliated with the university. There are 12 colleges located on the main campus and in nearby suburbs offering academic, sporting and cultural programs alongside accommodation for Melbourne students and faculty.

    Melbourne comprises 11 separate academic units and is associated with numerous institutes and research centres, including the Walter and Eliza Hall Institute of Medical Research, Florey Institute of Neuroscience and Mental Health, the Melbourne Institute of Applied Economic and Social Research and the Grattan Institute. Amongst Melbourne’s 15 graduate schools the Melbourne Business School, the Melbourne Law School and the Melbourne Medical School are particularly well regarded.

    Four Australian prime ministers and five governors-general have graduated from Melbourne. Nine Nobel laureates have been students or faculty, the most of any Australian university.

     
  • richardmitnick 5:40 pm on February 18, 2020 Permalink | Reply
    Tags: "South American volcano showing early warning signs of 'potential collapse' research shows", , , Geology, Tungurahua volcano in Ecuador – known locally as “The Black Giant”, University of Exeter,   

    From University of Exeter: “South American volcano showing early warning signs of ‘potential collapse,’ research shows” 

    1

    From University of Exeter

    One of South America’s most prominent volcanoes is producing early warning signals of a potential collapse, new research has shown [Earth and Planetary Science Letters].

    1
    Credit: CC0 Public Domain

    Tungurahua volcano in Ecuador – known locally as “The Black Giant” – is displaying the hallmarks of flank instability, which could result in a colossal landslide.

    New research, led by Dr James Hickey from the Camborne School of Mines, has suggested that the volcano’s recent activity has led to significant rapid deformation on the western flank.

    The researchers believe that the driving force causing this deformation could lead to an increased risk of the flank collapsing, causing widespread damage to the surrounding local area.

    The research recommends the volcano should be closely monitored to watch for stronger early warning signs of potential collapse.

    The study is published in the journal Earth & Planetary Science Letters.

    Dr Hickey, who is based at the University of Exeter’s Penryn Campus, Cornwall, said: “Using satellite data we have observed very rapid deformation of Tungurahua’s west flank, which our research suggests is caused by imbalances between magma being supplied and magma being erupted”.

    Tungurahua volcano has a long history of flank collapse, and has also been frequently active since 1999. The activity in 1999 led to the evacuation of 25,000 people from nearby communities.

    A previous eruption of Tungurahua, around 3,000 years ago, caused a prior, partial collapse of the west flank of the volcanic cone.

    This collapse led to a wide-spread debris avalanche of moving rock, soil, snow and water that covered 80 square kilometres – the equivalent of more than 11,000 football fields.

    Since then, the volcano has steadily been rebuilt over time, peaking with a steep-sided cone more than 5000 m in height.

    However, the new west flank, above the site of the 3000 year old collapse, has shown repeated signs of rapid deformation while the other flanks remain stable.

    The new research has shown that this deformation can be explained by shallow, temporary magma storage beneath the west flank. If this magma supply is continued, the sheer volume can cause stress to accumulate within the volcanic cone – and so promote new instability of the west flank and its potential collapse.

    Dr Hickey added: “Magma supply is one of a number of factors that can cause or contribute to volcanic flank instability, so while there is a risk of possible flank collapse, the uncertainty of these natural systems also means it could remain stable. However, it’s definitely one to keep an eye on in the future.”

    See the full article here .

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    2

    The University of Exeter is a public research university in Exeter, Devon, South West England, United Kingdom. It was founded and received its royal charter in 1955, although its predecessor institutions, St Luke’s College, Exeter School of Science, Exeter School of Art, and the Camborne School of Mines were established in 1838, 1855, 1863, and 1888 respectively.[5][6] In post-nominals, the University of Exeter is abbreviated as Exon. (from the Latin Exoniensis), and is the suffix given to honorary and academic degrees from the university.

    The university has four campuses: Streatham and St Luke’s (both of which are in Exeter); and Truro and Penryn (both of which are in Cornwall). The university is primarily located in the city of Exeter, Devon, where it is the principal higher education institution. Streatham is the largest campus containing many of the university’s administrative buildings[7] The Penryn campus is maintained in conjunction with Falmouth University under the Combined Universities in Cornwall (CUC) initiative. The Exeter Streatham Campus Library holds more than 1.2 million physical library resources, including historical journals and special collections.[8]

    Exeter was named the Sunday Times University of the Year in 2013[9] and was the Times Higher Education University of the Year in 2007.[10] It has maintained a top ten position in the National Student Survey since the survey was launched in 2005.[11] The annual income of the institution for 2017–18 was £415.5 million of which £76.1 million was from research grants and contracts, with an expenditure of £414.2 million.[1]

    Exeter is a member of the Russell Group of leading research-intensive UK universities[12] and is also a member of Universities UK, the European University Association, and the Association of Commonwealth Universities and an accredited institution of the Association of MBAs (AMBA).

     
  • richardmitnick 4:08 pm on February 18, 2020 Permalink | Reply
    Tags: "Fluid Pressure Changes Grease Cascadia’s Slow Aseismic Earthquakes", , , , , , Geology   

    From Eos: “Fluid Pressure Changes Grease Cascadia’s Slow Aseismic Earthquakes” 

    From AGU
    Eos news bloc

    From Eos

    2.18.20
    Mary Caperton Morton

    Twenty-five years’ worth of data allows scientists to suss out subtle signals deep in subduction zones.

    Cascadia subduction zone

    Cascadia plate zones

    1
    The study region followed the coast of Vancouver Island in British Columbia, one of the source regions for slow earthquakes along the Cascadia Subduction Zone. Credit: NASA

    Not all earthquakes make waves. During slow “aseismic” earthquakes, tectonic plates deep in subduction zones can slide past one another for days or even months without producing seismic waves. Why some subduction zones produce devastating earthquakes and tsunamis while others move benignly remains a mystery. Now a new study is shedding light on the behavior of fluids in faults before and after slow-slip events in the Cascadia Subduction Zone.

    Aseismic earthquakes, also known as episodic tremor and slip, were discovered about 20 years ago in the Cascadia Subduction Zone, where oceanic plates are descending beneath the North American plate at a rate of about 40 millimeters per year.

    4

    2
    Vancouver profile

    3
    Oregon profile

    This 1,000-kilometer-long fault has a dangerous reputation but has not produced a major earthquake since the magnitude 9.0 megathrust earthquake and tsunami that struck on 26 January 1700. Scientists think that some of Cascadia’s energy may be dissipated by regular aseismic events that take place deep in the fault zone roughly every 14 months.

    Episodic tremor and slip occur deep in subduction zones, and previous studies have suggested that these slow-slip events may be lubricated by highly pressurized fluids. “There are many sources of fluids in subduction zones. They can be brought down by the descending plate, or they can be generated as the downgoing plate undergoes metamorphic reactions,” said Pascal Audet, a geophysicist at the University of Ottawa in Ontario and an author on the new study, published in Science Advances.

    “At depths of 40 kilometers, the pressure exerted on the rocks is very high, which normally tends to drive fluids out, like squeezing a sponge,” Audet said. “However, these fluids are trapped within the rocks and are virtually incompressible. This means that fluid pressures increase dramatically, weakening the rocks and generating slow earthquakes.”

    This 1,000-kilometer-long fault has a dangerous reputation but has not produced a major earthquake since the magnitude 9.0 megathrust earthquake and tsunami that struck on 26 January 1700. Scientists think that some of Cascadia’s energy may be dissipated by regular aseismic events that take place deep in the fault zone roughly every 14 months.

    Eavesdropping on Slow Quakes

    To study how fluid pressures change during slow earthquakes, lead author Jeremy Gosselin, also at Ottawa, and Audet and colleagues drew upon 25 years of seismic data, spanning 21 slow-earthquake events along the Cascadia Subduction Zone. “By stacking 25 years of data, we were able to detect slight changes in the seismic velocities of the waves as they travel through the layers of oceanic crust associated with slow earthquakes,” Audet said. “We interpret these changes as direct evidence that pore fluid pressures fluctuate during slow earthquakes.”

    Audet and colleagues are still working to identify the cause and effect of the pore fluid pressure changes. “Is the change in fluid pressure a consequence of the slow earthquake? Or is it the opposite: Does an increase in pore fluid pressure somehow trigger the slow earthquake? That’s the next big question we’d like to tackle.”

    “I’m surprised and impressed they were able to isolate these signals,” said Michael Bostock, a geophysicist at the University of British Columbia in Vancouver who was not involved in the new study. “They’re very subtle, but they’re all pointing in the same direction.”

    Theoretical models, as well as other seismic studies on subduction zones in Japan and New Zealand, have offered supporting lines of evidence that pore fluids are redistributed at the boundaries of tectonic plates during slow-slip events, Audet said. “Other studies have offered somewhat indirect evidence for this idea, but our study offers the first direct evidence that fluid pressures do in fact fluctuate during slow earthquakes.”

    The next steps will be to conduct similar seismic studies on other subduction zones, Bostock said. It’s too soon to say whether this fluid behavior is universal to all slow-earthquake zones, but “there may be other factors at play as well, such as temperature and pressure, that create a sweet spot where slow earthquakes are more likely to occur,” he said. The right combination of overlapping factors may help explain why some fault zones record more aseismic events than others.

    Whether these changes in fluid pressures could be used to predict where and when a slow-slip event might occur is unknown, Bostock said, although “slow earthquakes are already more predictable than regular earthquakes.” In Cascadia, for example, they’re known to occur about every 14 months, give or take, for reasons that remain unclear. “Prediction is the holy grail of earthquake science, but it’s fraught with difficulties. Tectonic faults, despite their grand scale, are very sensitive to perturbations in ways we don’t clearly understand yet.”

    See the full article here .

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    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 3:40 pm on February 18, 2020 Permalink | Reply
    Tags: , , “Our hope is to expand our research to other areas of the world with similar risks of landslides including Alaska and Appalachia in the United States” said Sarah Kapnick., Climate Change and increased risks, , Geology, High Mountain Asia risk, In summer 2019 monsoon flooding and landslides in Nepal India and Bangladesh displaced more than 7 million people., , Most significantly the border region of China and Nepal could see a 30-70% increase in landslide activity., The study team first ran LHASA with NASA precipitation data from 2000-2019 and NOAA climate model data from 1982-2017., The study team used a NASA model that generates a “nowcast” estimating potential landslide activity triggered by rainfall in near real-time., The study team used NOAA’s model data to take LHASA into the future assessing precipitation and landslide trends in the future (2061-2100) versus the past (1961-2000).   

    From AGU GeoSpace Blog: “Climate change could trigger more landslides in High Mountain Asia” 

    From AGU GeoSpace Blog

    11 February 2020
    Jessica Merzdorf

    More frequent and intense rainfall events due to climate change could cause more landslides in the High Mountain Asia region of China, Tibet and Nepal, according to the first quantitative study of the link between precipitation and landslides in the region.

    High Mountain Asia stores more fresh water in its snow and glaciers than any place on Earth outside the poles, and more than a billion people rely on it for drinking and irrigation. The study team used satellite estimates and modeled precipitation data to project how changing rainfall patterns in the region might affect landslide frequency. The study team found that warming temperatures will cause more intense rainfall in some areas, and this could lead to increased landslide activity in the border region of China and Nepal.

    More landslides in this region, especially in areas currently covered by glaciers and glacial lakes, could cause cascading disasters like landslide dams and floods that affect areas downstream, sometimes hundreds of miles away, according to the new study in AGU’s journal Geophysical Research Letters.

    https://blogs.agu.org/geospace/files/2014/10/800px-Bergsturz_Randa.jpg
    A landslide in Randa, Switzerland. Credit: Wandervogel.

    High Mountain Asia stretches across tens of thousands of rugged, glacier-covered miles, from the Himalayas in the east to the Hindu Kush and Tian Shan mountain ranges in the west. As Earth’s climate warms, High Mountain Asia’s water cycle is changing, including shifts in its annual monsoon patterns and rainfall.

    2
    The model shows landslide risk for High Mountain Asia increasing in the summer months in the years 2061-2100, thanks to increasingly frequent and intense rainfall events. Summer monsoon rains can destabilize steep mountainsides, triggering landslides. Credit: NASA’s Earth Observatory/Joshua Stevens.

    Heavy rain, like the kind that falls during the monsoon season in June through September, can trigger landslides on the steep terrain, creating disasters that range from destroying towns to cutting off drinking water and transportation networks. In summer 2019, monsoon flooding and landslides in Nepal, India and Bangladesh displaced more than 7 million people. In order to predict how climate change might affect landslides, researchers need to know what future rainfall events might look like. But until now, the research making the landslide predictions has relied on records of past landslides or general precipitation estimate models.

    “Other studies have either addressed this relationship very locally, or by adjusting the precipitation signal in a general way,” said Dalia Kirschbaum, a research scientist at NASA’s Goddard Space Flight Center. “Our goal was to demonstrate how we could combine global model estimates of future precipitation with our landslide model to provide quantitative estimates of potential landslide changes in this region.”

    The study team used a NASA model that generates a “nowcast” estimating potential landslide activity triggered by rainfall in near real-time. The model, called Landslide Hazard Assessment for Situational Awareness (LHASA), assesses the hazard by evaluating information about roadways, the presence or absence of nearby tectonic faults, the types of bedrock, change in tree cover and the steepness of slopes. Then, it integrates current precipitation data from the Global Precipitation Measurement mission and Tropical Rainfall Measuring Mission. If the amount of precipitation in the preceding seven days is abnormally high for that area, then the potential occurrence of landslides increases.

    The study team first ran LHASA with NASA precipitation data from 2000-2019 and NOAA climate model data from 1982-2017. They compared the results from both data sets to NASA’s Global Landslide Catalog, which documents landslides reported in the media and other sources. Both data sets compared favorably with the catalog, giving the team confidence that using the modeled precipitation data would yield accurate forecasts.

    3
    NASA’s Global Landslide Catalog contains more than 1,000 records of landslides in High Mountain Asia between 2007 and 2017. Some of these events caused hundreds or thousands of fatalities. Credit: NASA’s Earth Observatory/Joshua Stevens.

    Finally, the study team used NOAA’s model data to take LHASA into the future, assessing precipitation and landslide trends in the future (2061-2100) versus the past (1961-2000). They found that extreme precipitation events are likely to become more common in the future as the climate warms, and in some areas, this may lead to a higher frequency of landslide activity.

    Most significantly, the border region of China and Nepal could see a 30-70% increase in landslide activity. The border region is not currently heavily populated, Kirschbaum said, but is partially covered by glaciers and glacial lakes. The combined impacts of more frequent intense rainfall and a warming environment could affect the delicate structure of these lakes, releasing flash floods and causing downstream flooding, infrastructure damage, and loss of water resources.

    The full human impact of increasing landslide risk will depend on how climate change affects glaciers and how populations and communities change. When they evaluated their model projections in the context of five potential population scenarios, the team found that most residents in the area will be exposed to more landslides in the future regardless of the scenario, but only a small proportion will be exposed to landslide activity increases greater than 20%.

    The study demonstrates new possibilities for research that could help decision-makers prepare for future disasters, both in High Mountain Asia and in other areas, said Kirschbaum.

    “Our hope is to expand our research to other areas of the world with similar risks of landslides, including Alaska and Appalachia in the United States,” said Sarah Kapnick, physical scientist at NOAA’s Geophysical Fluid Dynamics Laboratory and co-author on the study. “We’ve developed a method, figured out how to work together on a specific region, and now we’d like to look at the U.S. to understand what the hazards are now and in the future.”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    GeoSpace is a blog on Earth and space science, managed by AGU’s Public Information staff. The blog features posts by AGU writers and guest contributors on all sorts of relevant science topics, but with a focus on new research and geo and space sciences-related stories that are currently in the news.

    Do you have ideas on topics we should be covering? Would you like to contribute a guest post to the blog? Contact Peter Weiss at pweiss@agu.org.

     
  • richardmitnick 11:27 am on February 15, 2020 Permalink | Reply
    Tags: (DIC)-Dissolved Inorganic Carbon, (TA)-Total Alkalinity, , , , Geology, , , , The wet lab then becomes a bedlam of buckets containing rocks; corals; sponges; and shell fragments; occasional deep sea litter; and an assortment of marine creatures that I have never seen before., You need to know how to tie knots.   

    From Schmidt Ocean Institute: “Darling it’s better, Down in a Wet(ter) Lab at Sea” 

    From Schmidt Ocean Institute

    2.13.20
    Jill Brouwer

    1
    Cruise Log: The Great Australian Deep-Sea Coral and Canyon Adventure

    Trying to understand a constantly moving ocean system is a huge challenge. Accurately measuring the chemistry of the ocean is important for understanding many processes, including nutrient and carbon cycling; ocean circulation and movement of water masses; as well as ocean acidification and climate change. On this expedition, the water chemistry team has the important job of analyzing the seawater in three canyon systems. We are measuring Dissolved Inorganic Carbon (DIC) and Total Alkalinity (TA) on board, while also saving samples for later analysis of stable isotopes, trace elements, and nutrients.

    2
    Jill and Carlin using the CTD rosette to collect water samples from the depths of the Bremer Canyon.

    Knotty and Nice

    There are some quirks of successfully doing chemistry at sea that I definitely did not consider before this voyage. Firstly, you need to know how to tie knots. Making sure all the instruments, reagent bottles, and yourselves are secured is just as important as doing the actual chemistry. The precious sample counts for nothing if it flies across the room because you forgot to put it on a non-slip mat. The movement of the boat transforms normal lab activities into fun mini challenges – opening oven or fridge doors as the ship moves with the weather, pipetting as you hit a large wave, storing sample vials in a giant freezer. It is weird (but comforting) to see our analytical instruments strapped to the bench, and doing most of my work out of a sink – the safest place to keep samples. I particularly enjoy the arts and crafts component that comes with bubble wrapping and storing samples to prevent them from being damaged by sudden movements.

    After the chemistry work is done for the day, ROV SuBastian [below] comes aboard with all kinds of creepy-crawlies from the deep sea. All the biology and geology samples that have been collected from the dive are carried into the wet lab to be sorted, processed, and archived. The lab then becomes a bedlam of buckets containing rocks, corals, sponges, shell fragments, occasional deep sea litter, and an assortment of marine creatures that I have never seen before. Surrounding these specimens is an eclectic mix of scientists who all bring their own unique interests and passions to the group.

    3

    To name a few; Julie, Paolo, and their team are interested in finding calcifying corals for their paleoceanography studies. They study the chemistry of the ocean thousands of years ago, recorded by coral skeletons when they were formed. We also have Andrew from the Western Australian Museum, who is doing his PhD on specialized barnacles that live in sponges, but is interested in pretty much everything. It is not just the big things we are looking for either. Aleksey and Netra are on the lookout for tiny single-cell organisms called Foraminifera that we have found in the water column, sediments, and attached to things like corals and whale bones.

    4
    Netra, Jill, and Angela investigating the latest samples to arrive in the wet lab of R/V Falkor.

    5
    This Stephanocyanthus is a soft cup coral.

    6
    This Caryophylliidae is from a family of stony corals.

    Working in a wet lab at sea has its share of challenges, but considering the important scientific discoveries that are facilitated by us being out here, the cool (and in some cases totally new) marine life we are encountering, as well as the incredible views of sun glint and waves through the lab window, I would not choose to be anywhere else. To all the undergraduate students reading this, I encourage you to seek out as much volunteer/work experience as you can. Getting involved in science firsthand is an invaluable experience: you get to work with incredible people, gain useful skills, and learn so much more about yourself and your areas of interest than you can from the classroom. Perhaps most importantly, you get to share all the exciting things you learn with others!

    7

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Our Vision
    The world’s oceans understood through technological advancement, intelligent observation, and open sharing of information.

    Schmidt Ocean Institute RV Falkor

    Schmidt Ocean Institute ROV Subastian

    Schmidt Ocean Institute is a 501(c)(3) private non-profit operating foundation established in March 2009 to advance oceanographic research, discovery, and knowledge, and catalyze sharing of information about the oceans.

    Since the Earth’s oceans are a critically endangered and least understood part of the environment, the Institute dedicates its efforts to their comprehensive understanding across intentionally broad scope of research objectives.

    Eric and Wendy Schmidt established Schmidt Ocean Institute in 2009 as a seagoing research facility operator, to support oceanographic research and technology development focusing on accelerating the pace in ocean sciences with operational, technological, and informational innovations. The Institute is devoted to the inspirational vision of our Founders that the advancement of technology and open sharing of information will remain crucial to expanding the understanding of the world’s oceans.

     
  • richardmitnick 11:10 am on February 14, 2020 Permalink | Reply
    Tags: "Antarctic Ice Cores Might Be Older Than Dirt", , Cosmogenic nuclide dating, Geology,   

    From Eos: “Antarctic Ice Cores Might Be Older Than Dirt” 

    From AGU
    Eos news bloc

    From Eos

    6 February 2020 [Just now in social media]
    Jessie Hendricks
    contactjessiescience@gmail.com

    Using cosmogenic nuclide dating, scientists determined a 10-meter core just below the surface to be over a million years old.

    1
    Researchers in Ong Valley, Antarctica, take pit samples above the ice during a field mission. Pictured left to right: Dan Morgan (Vanderbilt University), Greg Balco (Berkeley Geochronology Center), and Marie Bergelin (University of North Dakota, Grand Forks). Credit: Jaakko Putkonen

    A little over 500 kilometers from McMurdo Station, nestled in the Transantarctic Mountain Range, is the Ong Valley. This small, arid valley is about 6 kilometers long by 2.5 kilometers wide, and records suggest it has been visited by fewer people than the Moon.

    Jaakko Putkonen, associate professor and director of the Harold Hamm School of Geology and Geological Engineering at the University of North Dakota, Grand Forks, has been to the Ong Valley three times. He loves being one of the few: “You never know what’s behind the big rock because nobody’s ever looked there,” he said. “There are no footprints anywhere. Nothing.”

    Marie Bergelin, Putkonen’s Ph.D. student, joined him on his 2017–2018 expedition, in which a critical research team from multiple universities drilled into the Ong Valley’s ice bed and recovered two 10-meter ice cores. Putkonen and Bergelin presented their findings during a poster session at AGU’s Fall Meeting 2019 in San Francisco, Calif.

    2
    Jaakko Putkonen holds up a piece of debris-laden ancient ice recovered from Ong Valley, Antarctica. Credit: Marie Bergelin.

    One of the oldest sections of the cores, according to Bergelin, is likely to be around 2.6 million years old and at least no younger than the dirt above it, which was dated at 1.6 million years old. Putkonen and Bergelin are quick to note that the core may be older or younger than 2.6 million years, however. Determining the date of ice is a complex process, Putkonen said, and the numbers come out more “as a range of scenarios” rather than one specific date.

    The trick to dating ice cores is not the ice itself, but quartz grains embedded in or around it. And the trick to preserving ice is the layer of dirt on top of it.

    Dating the Ice

    Scientists use cosmogenic nuclide dating [ArcticGlaciders.org], which analyzes isotopes produced in quartz by cosmic rays at or near Earth’s surface. “The longer time it’s exposed to the surface and sitting at the surface, the higher concentrations of isotopes build up,” Bergelin said.

    The cosmic rays that produce these isotopes penetrate only a few meters. Below that, the isotopes stop building up, which helps scientists predict the age of a subsection of Earth or ice containing the debris.

    Bergelin extracted quartz grains from the full length of a core to determine the age of the ice inside. As suspected, the oldest section was at the bottom of the core.

    Preserving the Ice

    It’s well known that a sufficient amount of debris acts as a shield for ice, preventing it from melting or sublimation, the process by which ice bypasses a liquid stage and turns directly into vapor. (Sublimation is common in extremely arid climates like Antarctica.) “The soil cover is critical to preserving [the ice],” Putkonen said, “but even then we don’t fully understand the [preservation] process.”

    What scientists do know is that as ice sublimates and disappears, dirt dispersed in the ice will be left behind. The more ice sublimates, the more layers of dirt and debris will build up. Eventually, this layer of dirt will become thick enough that it inhibits the ice underneath from sublimating. Less than 5 centimeters of the right kind of dirt will actually enhance the melting of ice, but a thicker layer, maybe around 30 centimeters or more, said Putkonen, “will act as an insulating blanket and preserve the ice.”

    Without the protection of 60 centimeters of dirt on top of the ice, the 10-meter cores collected by Putkonen and Bergelin might have sublimated away in just over 100 years. Instead, the ice in the core is over a million years old.

    2
    This partial section of one of the 10-meter ice cores was drilled from below a blanket of dirt in Ong Valley, Antarctica. Credit: Marie Bergelin

    Brenda Hall, a professor in the School of Earth and Climate Sciences at the University of Maine, wrote in an email to Eos, “Bergelin and Putkonen have demonstrated the great antiquity of the buried ice and its potential for providing a glimpse into an environment that existed in the distant past. Perhaps more exciting, their work implies that this site may not be a ‘one off’ location, but rather that there is potential for old ice throughout the Transantarctic Mountains that can be used to reconstruct Earth’s past.”

    Bergelin and Putkonen have already found pollen, DNA, dust, and atmospheric gases trapped inside of the ice cores, which they continue to analyze.

    “In a way this is like opening up a window into a snapshot of the past conditions,” Putkonen said. “Once we start understanding the system better, there could be opportunities for a whole new way of looking into paleoconditions through pockets of preserved ice.”

    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 12:31 pm on February 1, 2020 Permalink | Reply
    Tags: "Nearly barren Icelandic landscapes guide search for extraterrestrial life", , , , , Geology   

    From AGU GeoSpace Blog: “Nearly barren Icelandic landscapes guide search for extraterrestrial life” 

    From AGU GeoSpace Blog

    15 January 2020
    Kate S. Petersen

    Kate S. Petersen is a current student in the MIT Graduate Program in Science Writing.

    Scientists attempt to refine planetary rover survey strategies by studying Earth habitats similar to Mars.

    1
    FELDSPAR 2019 team discussing a plan for drone mapping at the Holuhraun volcanic eruption site. Pictured (right to left): Anna Simpson, Carlie Novak, and Amanda Stockton of Georgia Institute of Technology.
    Credit: Erika Rader.

    2
    The eruption in Holuhraun on 4 September 2014

    New research on microbial lifeforms living in nearly barren volcanic landscapes in Iceland may help scientists understand how best to search for life on other planets.

    Researchers with NASA’s FELDSPAR (Field Exploration and Life Detection Sampling for Planetary Analogue Research) project are studying the distribution of life in these harsh Icelandic environments to inform the search for hidden life signs on planets like Mars. So far, they have found that microbes at their study sites are often isolated in “hot spots” and that microbial communities are distributed differently in areas subjected to different geological resurfacing processes, such as wind or glaciation. They presented their results last month at AGU’s Fall Meeting 2019 in San Francisco.

    The search for extraterrestrial life is currently limited to remote sensing, with satellites and telescopes, and ground-based robotic missions, such as NASA’s Mars 2020 rover mission set to launch next year.

    NASA Mars 2020 rover schematic


    NASA Mars 2020 Rover

    Rovers can only collect and test a certain number of samples before their resources are exhausted, so sample selection must be strategic.

    Scientists suspect Mars was once warmer and wetter than it is now and could have harbored life. However, signs of past life or potential surviving lifeforms are not obvious. “What [FELDSPAR researchers] have been working on is trying to figure out how many samples we need to get in order to probabilistically sample that one region that has that biological hotspot,” said Amanda Stockton, a biochemist at Georgia Institute of Technology and co-principal investigator of the FELDSPAR project.

    It is the lack of widespread, obvious life that makes Icelandic volcanic environments an ideal choice as Martian analog sites. They are covered in tephra, ash or rocky material spewed from the volcanos. The tephra is dominated by basalt, a volcanic rock that makes up many regions on the surface of Mars. FELDSPAR researchers collect tephra samples and test them for DNA and ATP, a biomolecule that terrestrial life uses to transfer energy. While the researchers are analyzing signs of contemporary (extant) life in Iceland, they say that understanding these distribution patterns may also be useful for searching for biological signatures of extinct life on other planets.

    2
    Anna Simpson taking a depth core at Dyngjusandur, in east-central Iceland.
    Credit: Erika Rader.

    Jen Blank, who leads the NASA BRAILLE project to characterize signs of life in lava tubes and is not involved in FELDSPAR, praised the research. “It’s the first really systematic study on different scales that’s been done, because it’s so hard to do. And it takes a lot of time,” she said.

    Unfortunately, if these Icelandic analog sites are any indication, it could potentially take more samples than a rover could analyze to locate life signs on another planet, even if they are present, according to the researchers. Stockton described one area where the team analyzed nearly 400 samples and only two had high levels of biology.

    Given this reality, FELDSPAR researchers are attempting to refine search parameters by investigating whether there are any physical features in the environment that are correlated with pockets of life. If so, remote sensing technology from satellites or drones could be used to identify places that are most likely to harbor signs of life before a rover uses precious resources to actually analyze samples.

    This work is still in process, but the researchers have made some preliminary findings. According to FELDSPAR researcher Anna Simpson, a microbial ecologist at Georgia Institute of Technology, one potential environmental factor that could impact the distribution of life is the geological history of the area. “Life occurs in patches and along gradients in areas shaped by wind, while it is evenly distributed with a few seemingly random hotspots of high biological activity in areas impacted by recent glaciation,” she said.

    Simpson said the team has also begun evaluating average tephra grain size at a site as another potential predictive factor for biosignatures on Mars. “We’re really interested in whether the number of crevices in a mineral grain is going to affect how much life is there,” Simpson said. She explained that larger grains with more crevices could potentially shelter microbes from lethal UV radiation at the surface of Mars. “We actually do find that, where there’s really big chunks of basalt in the tephra, those tend to have more ATP,” said Simpson, who emphasized that more analysis was needed to confirm this pattern.

    The FELDSPAR researchers are still analyzing data from their last field season and plan to publish more results that may inform rover search techniques in the future. But it is already very clear that constraints on life and how it is distributed in space and time can differ depending on the environment, said Diana Gentry, a co-principle investigator on FELDSPAR and a microbiologist who specializes in instrumentation at NASA Ames Research Center. “That has [implications] for the assumptions you make about life on other worlds and…how you would go looking for it.”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    GeoSpace is a blog on Earth and space science, managed by AGU’s Public Information staff. The blog features posts by AGU writers and guest contributors on all sorts of relevant science topics, but with a focus on new research and geo and space sciences-related stories that are currently in the news.

    Do you have ideas on topics we should be covering? Would you like to contribute a guest post to the blog? Contact Peter Weiss at pweiss@agu.org.

     
  • richardmitnick 10:57 am on February 1, 2020 Permalink | Reply
    Tags: , , Geologist Melodie French, Geology, , ,   

    From Rice University: Women in STEM-“Fed grant backs Rice earthquake research” Geologist Melodie French 

    Rice U bloc

    From Rice University

    January 31, 2020

    Jeff Falk
    713-348-6775
    jfalk@rice.edu

    Mike Williams
    713-348-6728
    mikewilliams@rice.edu

    Geologist Melodie French wins National Science Foundation CAREER Award.

    1
    Rice University geologist Melodie French has earned a National Science Foundation CAREER Award to support her investigation of the tectonic roots of earthquakes and tsunamis. Photo by Jeff Fitlow.

    The tectonic plates of the world were mapped in 1996, USGS.

    Rice University geologist Melodie French is crushing it in her quest to understand the physics responsible for earthquakes.

    The assistant professor of Earth, environmental and planetary science has earned a prestigious CAREER Award, a five-year National Science Foundation (NSF) grant for $600,000 to support her investigation of the tectonic roots of earthquakes and tsunamis.

    CAREER awards support the research and educational development of young scholars likely to become leaders in their fields. The grants, among the most competitive awarded by the NSF, go to fewer than 400 scholars each year across all disciplines.

    For French, the award gives her Rice lab the opportunity to study rocks exhumed from subduction zones at plate boundaries that are often the source of megathrust earthquakes and tsunamis. Her lab squeezes rock samples to characterize the strength of the rocks deep underground where the plates meet.

    “Fundamentally, we hope to learn how the material properties of the rocks themselves control where earthquakes happen, how big one might become, what causes an earthquake to sometimes arrest after only a small amount of slip or what allows some to grow quite large,” French said.

    “A lot of geophysics involves putting out instruments to see signals that propagate to the Earth’s surface,” she said. “But we try to understand the properties of the rocks that allow these different phenomena to happen.”

    That generally involves putting rocks under extreme stress. “We squish rocks at different temperatures and pressures and at different rates while measuring force and strain in as many dimensions as we can,” French said. “That gives us a full picture of how the rocks deform under different conditions.”

    The lab conducts experiments on both exposed surface rocks that were once deep within subduction zones and rock acquired by drilling for core samples.

    2
    Rice University geologist Melodie French and graduate student Ben Belzer work with a rock sample. French has been granted a National Science Foundation CAREER Award to study the tectonic roots of earthquakes and tsunamis. Photo by Jeff Fitlow.

    I’m working with (Rice Professor) Juli Morgan on a subduction zone off of New Zealand where they drilled through part of the fault zone and brought rock up from about 500 meters deep,” French said. “But many big earthquakes happen much deeper than we could ever drill. So we need to go into the field to find ancient subduction rocks that have somehow managed to come to the surface.”

    French is not sure if it will ever be possible to accurately predict earthquakes. “But one thing we can do is create better hazard maps to help us understand what regions should be prepared for quakes,” she said.

    French is a native of Maine who earned her bachelor’s degree at Oberlin College, a master’s at the University of Wisconsin-Madison and a Ph.D. at Texas A&M University.

    The award, co-funded by the NSF’s Geophysics, Tectonics and Marine Geology and Geophysics programs, will also provide inquiry-based educational opportunities in scientific instrument design and use to K-12 students as well as undergraduate and graduate-level students.

    3
    Geologist Melodie French sets up an experiment in her Rice University lab. She has won a National Science Foundation CAREER Award, a prestigious grant given to young scholars likely to become leaders in their fields. (Credit: Jeff Fitlow/Rice University)

    See the full article here .


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


    Stem Education Coalition

    Rice U campus

    In his 1912 inaugural address, Rice University president Edgar Odell Lovett set forth an ambitious vision for a great research university in Houston, Texas; one dedicated to excellence across the range of human endeavor. With this bold beginning in mind, and with Rice’s centennial approaching, it is time to ask again what we aspire to in a dynamic and shrinking world in which education and the production of knowledge will play an even greater role. What shall our vision be for Rice as we prepare for its second century, and how ought we to advance over the next decade?

    This was the fundamental question posed in the Call to Conversation, a document released to the Rice community in summer 2005. The Call to Conversation asked us to reexamine many aspects of our enterprise, from our fundamental mission and aspirations to the manner in which we define and achieve excellence. It identified the pressures of a constantly changing and increasingly competitive landscape; it asked us to assess honestly Rice’s comparative strengths and weaknesses; and it called on us to define strategic priorities for the future, an effort that will be a focus of the next phase of this process.

     
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