The following igneous and sedimentary rock exercises were designed for elementary level science classes in Whitehall, Montana.  Although the photographs are specific to southwestern Montana, the learning exercises are applicable to all geographic localities!  Have fun learning about rocks!

IGNEOUS ROCKS

1. There are two main categories of igneous rocks - those that have cooled inside the earth, and those that have cooled on the earth's surface.  Click on this web site - http://csmres.jmu.edu/geollab/Fichter/IgnRx/Introigrx.html  and see if you can find the name for these two types of igneous rocks.

    A. _________________________________

    B. _________________________________

2. There are many types of intrusive igneous rocks.  Look at the photographs of granite, diorite, and gabbro at http://www.minsocam.org/MSA/K12/rkcycle/intrusives.html .   What kind of texture do you see in all the rock photographs? _________________________ Why do these rocks contain such large crystals? _______________________________________________________

3. The color of an igneous rock depends upon its mineral composition.  Click on this site - http://home.att.net/~cochrans/ignrok01.htm and use its igneous rock chart to decide the main minerals in:

    A. granite (a light-colored igneous rock) _____________________________

    B. diorite (a medium-colored igneous rock) ___________________________

    C. gabbro (a dark-colored igneous rock) _____________________________

4. Igneous intrusions are bodies of igneous rock that form when magma crystallizes underground.  Go to site - http://seis.natsci.csulb.edu/basicgeo/INTRUSIONS/INTRUSIONS.html and list three types of igneous intrusions:

    A. ______________________________

    B. ______________________________

    C. ______________________________

5. Extrusive igneous rocks are formed from volcanic eruptions.  Go to site - http://volcanoes.usgs.gov/Products/Pglossary/pglossary.html and answer the following questions:

   A. Look under "Type of Volcano or vent" and click on the following types of volcanoes 

    and write a brief description of each:

        1. caldera ________________________________________________________

        2. shield volcano __________________________________________________

        3. stratovolcano ___________________________________________________

    B. Now go to site - http://www.volcano.si.edu/gvp/usgs/ and list two areas of volcanic

     activity:

        1._______________________________________________________________

        2._______________________________________________________________

    C. To understand the general distribution of volcanic areas on Earth, go to site -

     http://volcanoes.usgs.gov/Hazards/Where/WhereHaz.html . Where are most volcanoes

     located? ______________________________________________________________

       _____________________________________________________________________

6. There are many types of extrusive igneous rocks.  Look at the hand sample photographs shown on site - http://www.cryst.bbk.ac.uk/~ubcg01d/5P/igneous.html .  Which rocks shown are formed from volcanic ash? _________________________________________  What rock is formed from lava?

 _____________________________________

7. Go to site - http://volcano.und.edu . Find two currently erupting volcanoes and list them here: ___________________________ and ________________________________   Are there volcanoes on other planets?  _________  If so, where would they be located?

 _______________________________________________________________________ 

 _______________________________________________________________________

8. Volcanoes can be both beneficial and hazardous to humans who live near them.  Click on this site - http://www.geo.mtu.edu/volcanoes/hazards/primer/ and answer the following questions:

   A. How are volcanoes beneficial to humans? 

        1._________________________________________________________

        2. _________________________________________________________

        3. _________________________________________________________

    B. What kind of volcanic hazards might someone encounter?

        1. _________________________________________________________

        2. _________________________________________________________

        3. _________________________________________________________

9. The Yellowstone region of Montana, Wyoming, and Idaho has been called a "Supervolcano".  Link to Jake Lowenstern's writings - http://www.agiweb.org/geotimes/june05/feature_supervolcano.html - based upon his watch at the Yellowstone Volcano Observatory and please answer the following questions:

   A. What is a supervolcano?  _________________________________________________

___________________________________________________________________________

   B.  When was the most recent caldera-forming eruption? 

   ___________________________________________________________________

    C. Do you think a large volcanic eruption is likely to occur within your lifetime?  

   ____________________________________________________________________

Scientists believe that the Yellowstone region is still an area of powerful volcanic forces.  Link to this web site - http://pubs.usgs.gov/fs/2005/3024/ . From your reading on this site, list three geologic activities presently occurring within Yellowstone that indicate powerful volcanic forces are going on.

 1.___________________________________________________________________  

 2. ___________________________________________________________________

3. ____________________________________________________________________

SEDIMENTARY ROCKS

 __________________________________________________________________________

__________________________________________________________________________

2. Let’s continue on through the rock cycle. What is sediment?________________________ What does happen to sediment when it is buried, compacted, and/or cemented? __________________________________________________________________________

3. Now please go to this site - http://sln.fi.edu/fellows/payton/rocks/create/sediment.htm. Look at the animated image showing sediment deposition. Why do you think sedimentary rocks are layered?

 __________________________________________________________________________

4. Some sedimentary rocks are formed from chemical components and/or broken shells in ocean water. Go to site - http://seis.natsci.csulb.edu/bperry/Sedimentary%20Rocks%20Tour/chemical_sedimentary_rocks.htm . Name two rocks that are formed in this way:

        A. ____________________________________________

        B. ____________________________________________

5. Coal is another type of sedimentary rock. Click on this site - http://www.athro.com/geo/trp/gub/coal.html  and read about coal. Please write a brief summary on how coal forms on the lines below: 

____________________________________________________________________________

6. Fossils can be found within sedimentary rocks. Click on http://www.montanadinosaurdigs.com/discover.htm to go to the Montana Museum of the Rockies home page. Please find two fossils that interest you! List them below:

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