Current Events

  • Kansas Legislator Proposes Bill to Outlaw Sustainability Education
    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of ...Read more

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    Kansas Legislator Proposes Bill to Outlaw Sustainability Education

    A bill has been introduced in the Kansas legislature this week that would prohibit the promotion of sustainability. Here is a link to the one-page bill: http://www.kslegislature.org/li/b2013_14/measures/documents/hb2366_00_0000.pdf. See report on Bloomberg News.
  • Earth's Center Is 1,000 Degrees Hotter Than Previously Thought, Synchrotron X-Ray Experiment Shows
    Scientists have determined the temperature near the Earth’s center to be 6000 degrees Celsius, 1000 ...Read more

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    Earth's Center Is 1,000 Degrees Hotter Than Previously Thought, Synchrotron X-Ray Experiment Shows

    Scientists have determined the temperature near the Earth’s center to be 6000 degrees Celsius, 1000 degrees hotter than in a previous experiment run 20 years ago. These measurements confirm geophysical models that the temperature difference between the solid core and the mantle above, must be at least 1500 degrees to explain why the Earth has a magnetic field. For more information about this study, see the press release from the European Synchrotron Radiation Facility.
  • Ocean Volcanic Rocks Contain Samples of Recycled Crust
    Scientists have long believed that lava erupted from certain oceanic volcanoes contains materials fr...Read more

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    Ocean Volcanic Rocks Contain Samples of Recycled Crust

    Scientists have long believed that lava erupted from certain oceanic volcanoes contains materials from the early Earth’s crust. But decisive evidence for this phenomenon has proven elusive. New research from a team including Carnegie’s Erik Hauri demonstrates that oceanic volcanic rocks contain samples of recycled crust dating back to the Archean era 2.5 billion years ago. Their work is published in Nature. Oceanic crust sinks into the Earth’s mantle at so-called subduction zones, where two plates come together. Much of what happens to the crust during this journey is unknown. Model-dependent studies for how long subducted material can exist in the mantle are uncertain and evidence of very old crust returning to Earth’s surface via upwellings of magma has not been found until now. For more information about these results, see the press release from the Carnegie Institution.
This diagram shows the Americas being separated from the Europe and Africa as the seafloor spreads. Continents are grey in color. Youngest seafloor is red and as seafloor gets older it becomes yellow, green and then blue.
Click on image for full size
NOAA/NESDIS/National Geophysical Data Center, Boulder, CO.

Seafloor Spreading

This diagram provides evidence of seafloor spreading by showing the ages of ocean floor in the Atlantic and eastern Pacific Oceans. The red colors are the youngest parts of the seafloor, where fresh new crust is formed as lava seeps up from the deep interior of the Earth at spreading ridges. As new crust forms at these spreading ridges, older crust, colored green in the diagram, moves away from the ridge. The blue portions are the oldest regions of the seafloor. They are either next to continents, which also contain very old rocks, or are near areas on Earth where subduction is taking place.

The diagram shows the American continents being separated from the Eurasian and African continents. This is a very fast model of what has happened to the Earth’s plates over the past 250 million years.


Last modified February 4, 2008 by Becca Hatheway.

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