Recent Changes

Tuesday, June 6

  1. page 4.4 Metamorphic Rocks edited ... Relate some common uses of metamorphic rocks. Introduction ... original rock. {http://…
    ...
    Relate some common uses of metamorphic rocks.
    Introduction
    ...
    original rock.
    {http://www.ck12.org/ck12/images?id=309187} Example of platy layers in metamorphic rock.
    The platy layers in this large outcrop of metamorphic rock show the effects of pressure on rocks during metamorphism.
    Metamorphism
    ...
    one direction.
    {http://www.ck12.org/ck12/images?id=310923} A foliated metamorphic rock.
    A foliated metamorphic rock.
    ...
    within Earth:
    Regional metamorphism: Changes in enormous quantities of rock over a wide area caused by the extreme pressure from overlying rock or from compression caused by geologic processes. Deep burial exposes the rock to high temperatures.
    Contact metamorphism: Changes in a rock that is in contact with magma because of the magma’s extreme heat.
    ...
    parent rock.
    Common Metamorphic Rocks|| Picture || Rock Name || Type of Metamorphic Rock || Comments ||
    {http://www.ck12.org/ck12/images?id=309213}
    ...
    Metamorphism of conglomerate
    Uses of Metamorphic Rocks
    ...
    and paper.
    {http://www.ck12.org/ck12/images?id=309201} A decorative marble vase.
    Marble is used for decorative items and in art.
    ...
    metamorphic rocks.
    {http://www.ck12.org/ck12/images?id=309190} Showing crushed quartzite that is used under railroad tracks because of its hardness and durability.
    Crushed quartzite is sometimes placed under railroad tracks because it is very hard and durable.
    ...
    Film: The Living Rock: Earth’s Continental Crust \http://media.wr.usgs.gov/movies/index.html?id=living_rock
    Vocabulary
    ...
    existing rock.
    Points to Consider
    What type of rock forms if an existing rock heats up so much that it melts completely and then forms a different rock?
    ...
    Relate some common uses of metamorphic rocks.
    Introduction
    ...
    original rock.
    {http://www.ck12.org/ck12/images?id=309187} Example of platy layers in metamorphic rock.
    The platy layers in this large outcrop of metamorphic rock show the effects of pressure on rocks during metamorphism.
    Metamorphism
    ...
    one direction.
    {http://www.ck12.org/ck12/images?id=310923} A foliated metamorphic rock.
    A foliated metamorphic rock.
    ...
    within Earth:
    Regional metamorphism: Changes in enormous quantities of rock over a wide area caused by the extreme pressure from overlying rock or from compression caused by geologic processes. Deep burial exposes the rock to high temperatures.
    Contact metamorphism: Changes in a rock that is in contact with magma because of the magma’s extreme heat.
    ...
    parent rock.
    Common Metamorphic Rocks|| Picture || Rock Name || Type of Metamorphic Rock || Comments ||
    {http://www.ck12.org/ck12/images?id=309213}
    ...
    Metamorphism of conglomerate
    Uses of Metamorphic Rocks
    ...
    and paper.
    {http://www.ck12.org/ck12/images?id=309201} A decorative marble vase.
    Marble is used for decorative items and in art.
    ...
    metamorphic rocks.
    {http://www.ck12.org/ck12/images?id=309190} Showing crushed quartzite that is used under railroad tracks because of its hardness and durability.
    Crushed quartzite is sometimes placed under railroad tracks because it is very hard and durable.
    ...
    Film: The Living Rock: Earth’s Continental Crust \http://media.wr.usgs.gov/movies/index.html?id=living_rock
    Vocabulary
    ...
    existing rock.
    Points to Consider
    What type of rock forms if an existing rock heats up so much that it melts completely and then forms a different rock?
    (view changes)

Wednesday, May 24

  1. page 5.1 Energy Resources edited ... Classify different energy resources as renewable or non-renewable. Introduction ... to fun…
    ...
    Classify different energy resources as renewable or non-renewable.
    Introduction
    ...
    to function.
    The Need for Energy
    ...
    that food.
    People

    People
    also use
    ...
    (Figure below).
    {http://www.ck12.org/ck12/images?id=309224} Electrical transmission tower.
    Electrical transmission towers like the one shown in this picture help deliver the electricity people use for energy every day.
    ...
    changing forms.
    {http://www.ck12.org/ck12/images?id=310804}
    ...
    (I&E 1e): http://www.youtube.com/watch?v=v-Z2-jxCqVw&feature=relatedhttp://www.youtube.com/watch?v=v-Z2-jxCqVw&feature=related (6:01). v-Z2-jxCqVw?f=videos&c=ytapi-CK12Foundation-Flexrwikiimport-fg5akohk-0&d=AT8BNcsNZiISDLhsoSt-gqIO88HsQjpE1a8d1GxQnGDm&app=youtube_gdata
    ...
    potential energy.
    Animations

    Animations
    showing the
    ...
    following sites.
    http://www.physicsclassroom.com/mmedia/energy/se.cfm.
    http://www.physicsclassroom.com/mmedia/energy/ce.cfm.
    http://www.physicsclassroom.com/mmedia/energy/dg.cfm.
    Energy, Fuel, and Heat
    ...
    chemical change.
    What

    What
    are some
    ...
    used for?
    Food is fuel for your body.
    Sunlight is the energy plants need to make food by photosynthesis.
    ...
    {http://www.ck12.org/ck12/images?id=310943} Fire.
    A controlled fire.
    ...
    the fire.
    Types of Energy Resources
    Energy resources are either renewable or non-renewable. Non-renewable resources are used faster than they can be replaced so the supply available to society is limited (see example in Figure below). Renewable resources will not run out because they are replaced as quickly as they are used. Can you think of some renewable and non-renewable energy sources?
    ...
    Anthracite coal is a non-renewable energy resource.
    Non-renewable Resources
    ...
    Atmosphere chapters.
    Renewable Resources
    ...
    even now.
    Important Things to Consider about Energy Resources
    ...
    into energy.
    For

    For
    example, if
    ...
    energy resource.
    Lesson Summary
    According to the law of conservation of energy, energy is neither created nor destroyed.
    ...
    Some of the Earth science news on this website is related to energy: http://www.earthportal.org/
    Vocabulary
    ...
    in molecules.
    Points to Consider
    How long do fossil fuels take to form?
    (view changes)

Monday, April 3

  1. page 6.4 Theory of Plate Tectonics edited ... When the concept of seafloor spreading came along, scientists recognized that it was the mecha…
    ...
    When the concept of seafloor spreading came along, scientists recognized that it was the mechanism to explain how continents could move around Earth’s surface. Like the scientists before us, we will now merge the ideas of continental drift and seafloor spreading into the theory of plate tectonics. Continental drift and the mechanism of seafloor spreading create plate tectonics: http://video.yahoo.com/watch/1595682/5390276
    Earth’s Tectonic Plates
    ...
    earthquake occurs.
    Earthquake

    Earthquake
    epicenters outline
    ...
    (Figure below).
    {http://www.ck12.org/ck12/images?id=309297}
    Earthquakes outline the plates.
    ...
    {http://www.ck12.org/ck12/images?id=309249}
    The lithospheric plates and their names. The arrows show whether the plates are moving apart, moving together, or sliding past each other.
    ...
    fingernails grow.
    How Plates Move
    If seafloor spreading drives the plates, what drives seafloor spreading? Picture two convection cells side-by-side in the mantle as in Figure below).
    ...
    {http://www.ck12.org/ck12/images?id=309237}
    Mantle convection drives plate tectonics. Hot material rises at mid-ocean ridges and sinks at deep sea trenches, which keeps the plates moving along the Earth
    ...
    these animations:
    http://www.youtube.com/watch?v=p0dWF_3PYh4; *http://earthguide.ucsd.edu/eoc/teachers/t_tectonics/p_convection2.html
    Plate Boundaries
    ...
    each other?
    Divergent plate boundaries: the two plates move away from each other.
    Convergent plate boundaries: the two plates move towards each other.
    Transform plate boundaries: the two plates slip past each other.
    ...
    found there.
    Divergent Plate Boundaries
    Plates move apart at mid-ocean ridges where new seafloor forms. Between the two plates is a rift valley. Lava flows at the surface cool rapidly to become basalt but deeper in the crust the magma cools more slowly to form gabbro. So the entire ridge system is igneous rock that is either extrusive or intrusive. Earthquakes are common at mid-ocean ridges since the movement of magma and oceanic crust result in crustal shaking. The vast majority of mid-ocean ridges are located deep below the sea (Figure below) and (Figure below).
    ...
    USGS animation of divergent plate boundary at mid-ocean ridge: http://earthquake.usgs.gov/learn/animations/animation.php?flash_title=Divergent+Boundary&flash_file=divergent&flash_width=500&flash_height=200
    Divergent plate boundary animation: http://www.iris.edu/hq/files/programs/education_and_outreach/aotm/11/AOTM_09_01_Divergent_480.mov
    ...
    between continents.
    {http://www.ck12.org/ck12/images?id=309242}
    The Arabian, Indian, and African plates are rifting apart, forming the Great Rift Valley in Africa. The Dead Sea fills the rift with seawater.
    Convergent Plate Boundaries
    ...
    and earthquakes.
    Ocean-continent:

    Ocean-continent:
    When oceanic
    ...
    continental arc.
    {http://www.ck12.org/ck12/images?id=309258}
    Subduction of an oceanic plate beneath a continental plate causes earthquakes and forms a line of volcanoes known as a continental arc.
    ...
    {http://www.ck12.org/ck12/images?id=309252}
    The Cascade Mountains of the Pacific Northwest are a continental arc.
    ...
    (Figure below).
    {http://www.ck12.org/ck12/images?id=309243}
    The Sierra Nevada batholith cooled beneath a volcanic arc roughly 200 million years ago. The rock is well exposed here at Mount Whitney. Similar batholiths are likely forming beneath the Andes and Cascades today.
    ...
    Japan is an arc-shaped island arc composed of volcanoes off the Asian mainland, as seen in this satellite image.
    An animation of an ocean continent plate boundary is seen here: http://www.iris.edu/hq/files/programs/education_and_outreach/aotm/11/AOTM_09_01_Convergent_480.mov
    ...
    large earthquakes.
    {http://www.ck12.org/ck12/images?id=309267}
    In continent-continent convergence, the plates push upward to create a high mountain range.
    ...
    A short animation of the Indian Plate colliding with the Eurasian Plate: http://www.scotese.com/indianim.htm
    An animation of the Himalaya rising: http://www.youtube.com/watch?v=ep2_axAA9Mw&NR=1
    ...
    years ago.
    Transform Plate Boundaries
    ...
    (Figure below).
    {http://www.ck12.org/ck12/images?id=309296}
    Figure At the San Andreas Fault in California, the Pacific Plate is sliding northeast relative to the North American plate, which is moving southwest. At the northern end of the picture, the transform boundary turns into a subduction zone.
    ...
    (Figure below)?
    A transform plate boundary between the Pacific and North American plates creates the San Andreas Fault, the world’s most notorious transform fault.
    Just offshore, a divergent plate boundary, Juan de Fuca ridge, creates the Juan de Fuca plate.
    ...
    {http://www.ck12.org/ck12/images?id=325746}
    {http://www.ck12.org/ck12/images?id=310804}
    ...
    video (3b): http://www.youtube.com/watch?v=ifke1GsjNN0http://www.youtube.com/watch?v=ifke1GsjNN0 (4:50). ifke1GsjNN0?f=videos&c=ytapi-CK12Foundation-Flexrwikiimport-fg5akohk-0&d=AT8BNcsNZiISDLhsoSt-gqIO88HsQjpE1a8d1GxQnGDm&app=youtube_gdata
    Earth’s Changing Surface
    ...
    moving plates.
    In

    In
    the map
    ...
    following questions:
    {http://www.ck12.org/ck12/images?id=325747}
    What is the geologic origin of the Cascades Range?
    ...
    {http://www.ck12.org/ck12/images?id=309259}
    About 200 million years ago, the Appalachian Mountains of eastern North America were probably once as high as the Himalaya, but they have been weathered and eroded significantly since the breakup of Pangaea.
    ...
    (Figure below).
    {http://www.ck12.org/ck12/images?id=315480}
    Scientists think that the creation and breakup of a supercontinent takes place about every 500 million years. The supercontinent before Pangaea was Rodinia. A new continent will form as the Pacific ocean disappears.
    This animation shows the movement of continents over the past 600 million years beginning with the breakup of Rodinia: http://earthguide.ucsd.edu/eoc/teachers/t_tectonics/p_plate_reconstruction_blakey.html
    Intraplate Activity
    ...
    the hotspot.
    An animation of the creation of a hotspot chain is seen here: http://earthguide.ucsd.edu/eoc/teachers/t_tectonics/p_hawaii.html
    {http://www.ck12.org/ck12/images?id=309250}
    ...
    {http://www.ck12.org/ck12/images?id=309247}
    The Hawaiian chain continues into the Emperor Seamounts. The bend in the chain was caused by a change in the direction of the Pacific plate 43 million years ago. Using the age and distance of the bend, geologists can figure out the speed of the Pacific plate over the hotspot.
    ...
    (Figure below).
    {http://www.ck12.org/ck12/images?id=315490}
    Volcanic activity above the Yellowstone hotspot on the North American Plate can be traced from 15 million years ago to its present location.
    Plate Tectonics Theory
    ...
    explains why:
    Earth's geography has changed through time and continues to change today.
    some places are prone to earthquakes while others are not.
    certain regions may have deadly, mild or no volcanic eruptions.
    mountain ranges are located where they are.
    ...
    of life.
    Lesson Summary
    Plates of lithosphere move because of convection currents in the mantle. One type of motion is produced by seafloor spreading.
    ...
    Why are there no volcanoes along transform plate boundaries? At continent-continent convergent plate boundaries?
    Vocabulary
    ...
    granitic rock.
    Points to Consider
    On the map in Figure 3 above, the arrows show the directions that the plates are going. The Atlantic has a mid-ocean ridge, where seafloor spreading is taking place. The Pacific Ocean has many deep sea trenches, where subduction is taking place. What is the future of the Atlantic plate? What is the future of the Pacific plate?
    (view changes)

Tuesday, February 28

  1. page 14. Earth's Oceans edited dumb science Lessons Maine Connections

    dumb science
    Lessons
    Maine Connections
    (view changes)
  2. page 14.4 Ocean Life edited freack oceans oceans suck butthole

    freack oceans oceans suck butthole

    (view changes)
  3. page 14.4 Ocean Life edited freack freack oceans oceans suck butthole
    freack
    freack
    oceans oceans suck butthole

    (view changes)
  4. page 14.4 Ocean Life edited freack oceans
    freack oceans
    (view changes)

Wednesday, February 8

  1. page 11.3 Absolute Ages of Rocks edited ... Give four examples of radioactive materials that are used to date objects, and explain how eac…
    ...
    Give four examples of radioactive materials that are used to date objects, and explain how each is used.
    Describe how scientists know earth is billions of years old.
    papi chulo
    Introduction
    What was missing from the early geologic time scale? While the order of events was given, the dates at which the events happened were not. With the discovery of radioactivity in the late 1800s, scientists were able to measure the exact age of some rocks in years. Absolute dating allows scientists to assign numbers to the breaks in the geologic time scale. Radiometric dating and other forms of absolute age dating allowed scientists to get an absolute age from a rock or fossil.
    Tree Ring Dating
    ...
    (Figure below).
    {http://www.ck12.org/ck12/images?id=309435}
    Cross-section showing growth rings.
    ...
    time period.
    Scientists

    Scientists
    have created
    ...
    ancient structures.
    An example of how tree-ring dating is used to date houses in the United Kingdom is found in this article http://www.periodproperty.co.uk/ppuk_discovering_article_013.shtml.
    Ice Cores and Varves
    ...
    {http://www.ck12.org/ck12/images?id=309447}
    Ice core section showing annual layers.
    ...
    thinner layer.
    {http://www.ck12.org/ck12/images?id=325764}
    Ancient varve sediments in a rock outcrop.
    Age of Earth
    ...
    years ago.
    In

    In
    1892, William
    ...
    take place.
    {http://www.ck12.org/ck12/images?id=309425}
    Lord Kelvin.
    Thomson’s calculations were soon shown to be flawed when radioactivity was discovered in 1896. Radioactivity is the tendency of certain atoms to decay into lighter atoms, a process that emits energy. Radioactive decay of elements inside Earth’s interior provides a steady source of heat, which meant that Thomson had grossly underestimated Earth’s age.
    Radioactive Decay
    ...
    about atoms.
    Some

    Some
    isotopes are
    ...
    (Table below):
    Types of Radioactive Decay|| Particle || Composition || Effect on Nucleus ||
    Alpha
    ...
    1 electron
    One neutron decays to form a proton and an electron. The electron is emitted.
    ...
    (Figure below).
    {http://www.ck12.org/ck12/images?id=315509}
    A parent emits an alpha particle to create a daughter.
    ...
    0.391
    99.609
    ...
    (Figure below).
    {http://www.ck12.org/ck12/images?id=309438}
    Decay of an imaginary radioactive substance with a half-life of one year.
    An animation of half-life: http://einstein.byu.edu/~masong/htmstuff/Radioactive2.html
    ...
    half lives.
    {http://www.ck12.org/ck12/images?id=310804}
    ...
    (I&E 1e): http://www.youtube.com/watch?v=UbwMW7Q6F3Ehttp://www.youtube.com/watch?v=UbwMW7Q6F3E (4:46).
    UbwMW7Q6F3E?f=videos&c=ytapi-CK12Foundation-Flexrwikiimport-fg5akohk-0&d=AT8BNcsNZiISDLhsoSt-gqIO88HsQjpE1a8d1GxQnGDm&app=youtube_gdata
    ...
    1j, 1k): http://www.youtube.com/watch?v=zcavPAFiG14&feature=relatedhttp://www.youtube.com/watch?v=zcavPAFiG14&feature=related (9:55).
    Radiometric Dating of Rocks
    ...
    they calculate.
    Radiocarbon Dating
    ...
    (Figure below).
    {http://www.ck12.org/ck12/images?id=321303}
    Carbon isotopes from the black material in these cave paintings places their creating at about 26,000 to 27,000 years BP (before present).
    ...
    through time.
    Plants

    Plants
    remove all
    ...
    of carbon-12.
    A video of carbon-14 decay is seen here: http://www.youtube.com/watch?v=81dWTeregEA; a longer explanation is here: http://www.youtube.com/watch?v=udkQwW6aLik&feature=related.
    Potassium-Argon Dating
    ...
    that crystal.
    Potassium

    Potassium
    is common
    ...
    human ancestors.
    Potassium-argon dating is explained here: http://id-archserve.ucsb.edu/anth3/courseware/chronology/09_potassium_argon_dating.html
    Uranium-Lead Dating
    ...
    radiometric dating.
    Uranium-238 decays to lead-206 with a half-life of 4.47 billion years.
    Uranium-235 decays to form lead-207 with a half-life of 704 million years.
    ...
    of uranium.
    {http://www.ck12.org/ck12/images?id=309423}
    Zircon crystal.
    ...
    the planet.
    Limitations of Radiometric Dating
    ...
    have limits:
    1.

    1.
    The material
    ...
    be accurate.
    2.

    2.
    Radiometric dating
    ...
    sedimentary rock.
    Using

    Using
    a combination
    ...
    increasingly accurate.
    All of this evidence comes together to pinpoint the age of Earth at 4.6 billion years. A video discussing the evidence for this is found here: http://www.youtube.com/watch?v=w5369-OobM4
    The age of Earth is also discussed in this video: http://www.youtube.com/watch?v=lplcRdNDcps&feature=channel
    ...
    The concentrations of several radioactive isotopes (e.g. carbon-14, potassium-40, uranium-235 and -238) and their daughter products are used to accurately determine the age of rocks and organic remains.
    Review Questions
    ...
    or event.
    2.

    2.
    A radioactive
    ...
    atoms remain?
    3.

    3.
    A scientist
    ...
    the cloth?
    {http://www.ck12.org/ck12/images?id=309446}
    Carbon-decay graph.
    ...
    your choices.
    4.) A fossilized trilobite from a bed of sandstone that is about 500 million years old.
    3.) The fur of a woolly mammoth that was recently recovered, frozen in a glacier.
    2.) A 1-million-year-old bed of volcanic ash that contains the footprints of human ancestors.
    ...
    of granite.
    5.

    5.
    Why is
    ...
    over time?
    Further Reading / Supplemental Links
    Using tree rings and ice cores to track El Nino events: http://www.pbs.org/wgbh/nova/elnino/reach/living.html
    The radiometric time scale and its use for geologists: http://pubs.usgs.gov/gip/geotime/radiometric.html.
    Vocabulary
    ...
    in years.
    Points to Consider
    Why are techniques for dating, such as using tree rings, ice cores, and varves only useful for events that occurred in the last few thousand years?
    (view changes)

Tuesday, February 7

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