• Rock Cycle 


    Rock Cycle Rock Cycle


    Learn More About Rocks Below...

    Rocks Intro



    A rock is a naturally occurring solid mixture of one or more minerals, or organic matter  .There are three types of rock:   Igneous, Sedimentary, and Metamorphic.


    Igneous Rock is formed when magma cools deep within the earth or on the surface.

    Wind and rain erodes rock and deposits rock particles in layers at the bottom of bodies of water, such as the ocean.

    Layers of sediment eventually cement together forming sedimentary rock.

    Heat and pressure around sedimentary rock can transform it into metamorphic rock.

    Metamorphic rock is eventually melted inside the earth and turned back into magma, and the rock cycle repeats.


    Igneous Rock:  rocks formed by the cooling and solidifying of molten materials.  Igneous rocks can form beneath the Earth’s surface, or at its surface, as lava.

    Sedimentary Rock:  rock that has formed through the deposition and solidification of sediment, especially sediment transported by water, ice, and wind.  Sedimentary rocks are often deposited in layers, and frequently contain fossils.

    Metamorphic Rock:  rock that was once one form of rock but has changed to another under the influence of heat or pressure without passing through a liquid phase.

    Rocks can be classified into three main types:  igneous, metamorphic, and sedimentary.

    Use the table below to identify the characteristics of different types of rock:






    The rock cycle shows that any rock can turn into any other type of rock.

    1. Through the process of HEAT & PRESSURE, igneous and sedimentary rock become METAMORPHIC rock.
    2. Through the process of WEATHERING & EROSION, metamorphic and igneous rock become SEDIMENTARY rock.
    3. Through the process of MELTING, sedimentary and metamorphic rock become IGNEOUS rock.


    Erosion: the process by which the surface of the earth is worn away by the action of water, wind, glaciers, and waves.

    Weathering: the various mechanical and chemical processes that cause exposed rock to decompose (ie: rain, wind, freezing and melting).

    Sediment: particles of rock that have been broken down by weathering and erosion.


    Volcanoes and Earthquakes! Learn about 3 types of rocks

    Geo Mysteries-Great animations

    Interactive Rock Cycle
    Smithsonian Kids-All about rock collecting

    Plate Tectonics


    Gem Stones Minerals Matter
    Rocks for kids Rock Cycle Fun
    KIDS-GEO Rock Collecting
    Rocks and Fossils

    What does a Geologist Do ? Click here to find out.



    Rock Cycle Song
    (Sing to the tune of "Row, Row, Row Your Boat")

    Has been formed in layers
    Often found near water sources
    With fossils from decayers

    Then there's IGNEOUS rock
    Here since Earth was born
    Molten Lava, cooled and hardened
    That's how it is formed

    These two types of rocks
    Can also be transformed
    With pressure, heat and chemicals
    METAMORPHIC they'll become



    Crust:  The Earth’s crust is composed of oceanic crust and continental crust.  Oceanic crust is the crust on the ocean floor.  It is less than 10 km thick, and made of mostly basalt rock and contains the elements silicon, oxygen, iron, and magnesium.  The oceanic crust moves on top of the asthenosphere because of convection currents in the hot mantle.  Continental crust is the crust that contains Earth’s continents and averages about 32 km thick.  Underneath mountains, the continental crust can reach a thickness of 70 km.  It’s primarily made of granite rock, and contains the elements silicon, oxygen, aluminum, calcium, sodium, and potassium.  The continental crust moves on top of the asthenosphere because of convection currents in the hot mantle.  The crust is the least dense of all Earth’s layers.

    Mantle:  The mantle is the largest layer of the Earth and is located directly above the outer core.  The mantle is roughly 2900 km thick and contains about 80% of the volume of the Earth.  The mantle is composed mostly of the elements silicon, oxygen, iron, and magnesium.  The density of the mantle increases with depth, as do temperature and pressure.

    Outer Core:  The outer core is about 2250 km thick.  The outer core is made of the metals iron and nickel.  The temperature ranges from 2200-5000 degrees Celsius, and the heat makes the iron and nickel molten, or change into a hot liquid.

    Inner Core:  The inner core is about 1300 km thick.  The temperature of the inner core reaches 5000 degrees Celsius.  It is made of iron and nickel.  But unlike the outer core, the enormous pressure at this depth pushes the particle of iron and nickel so tightly together that the elements remain solid.

    Layers of the Earth vidio clip below

    The Earth is made of layers, each with its own distinct chemical and physical properties.  Scientists use earthquakes to study the Earth’s interior.

    Discuss how scientists study the structure of the Earth’s interior. Recognize that an understanding of the motion of earthquake waves can help scientists formulate hypotheses about the Earth’s interior. Compare and contrast the different layers of the Earth.

    1. Physical Properties (characteristics):
    As you travel from the surface of the earth towards the interior:
    Temperature increases
    Density Increases
    Pressure increases
    Viscocity decreases

    1. Composition(what it’s made of):
      Crust: solid rock
      Mantle: melted rock
      Outer Core: liquid iron
      Inner Core: solid iron and nickel
    2. Major layers of the Earth(from surface to interior):
      Crust Mantle Outer Core Inner Core
    3. Plate Movement:
      The plates of the lithosphere float on the upper mantle. This part of the mantle is called the asthenosphere. The consistency of the asthenosphere is like silly putty. The asthenosphere is hot, and, like silly putty, it can flow. The movement of the plates of the lithosphere on top of the slowly moving asthenosphere accounts for the formation of many mountains and volcanoes, as well as for earthquakes.
    4. Mantle Structure:
      The upper mantle structure is rigid and cool. The bottom mantle structure is hot and plastic-like. Movement of this part of the mantle can cause mountains and volcanoes to form.
    5. How are the Earth’s interior and the ocean floor related?
      The ocean floor is the closest part of the surface to the inside of the Earth. Earthquake waves are studied to see how far in the core of the Earth is.

    ALSO: If a boat wants to know how far down the ocean floor is, or where bumps on the bottom of the ocean are, they use sonar and then time how long the signals take to bounce back to the boat again.


    1. How do earthquake waves help identify the layers of the earth?
      Scientists know that P-waves can travel through solids and liquids, but S-waves can only travel through solids. Because of the variety of thickness in the Earth’s layers, scientists can detect the speed it takes for the waves of an earthquake to go through the Earth and hit the other side.

    How deep have humans been into the earth?

    Drilling into the Mantle (Click on the links below)

    Project Mohole: First attempt to drill into the mantle in the 1960s.

    A new attempt: Here is a National Geographic article about how scientists are using new technology to try again.

    Kola Superdeep Borehole, Russia:  A scientific drilling project in the former Soviet Union that attempted to drill as deep as possible into the Earth’s crust.  The project began in 1970 and reached a final depth of 12,262 meters (40,230 ft) in 1989.  It is the deepest hole ever drilled.


    Rock Cycle

    Getting into the Fossil Record webquest

    Students used the geologic time scale app on the iPods to add information to the geologic time scale handout they received in class. Here’s a copy of the handout: Geologic time scale2 that matches app
    Here’s a link to the free app you can download on your own iPod or iPhone:https://itunes.apple.com/us/app/geotimescale/id327090162?mt=8

    We also began working on a fossil webquest:
    Getting into the fossil record scavenger hunt
    You can answer the questions on the webquest by going to the University of California Museum of Paleontology website:

    Fossil Lab and Flow Map

    Now that our week of CRT testing and wacky bell schedules has come to an end, we are getting back to work! We are viewing student PowerPoints/videos created for the plate tectonics project (the deadline for these was last Friday, April 19, and they were assigned over four weeks ago). We are also finishing up a fossil lab that we worked on last week as time allowed.

    Students have homework tonight that is due tomorrow. They are creating a flow map to show the steps involved in the creation of a mold and cast fossil. See: Fossil mold & cast flow map