Does a rock remain the same forever?

No, rock changes from one rock type to another.

Weathering

Erosion

Heat

Pressure

What are some of the forces that change rocks?

Weathering • Weathering – the process of breaking rock

into silt, sand, clay, and other tiny pieces, called sediment.

• Agents of weathering – wind, water, and ice.

Two types of weathering

1. Physical weathering – changes the size

and shape of rocks.

Examples of Physical Weathering

• In cold temperatures, water freezes and expands. This creates forces that can crack rock and pavement.

• Ground water is precipitation that soaks into the ground and soften the mountains.

• Run-off is precipitation that does not soak into the ground, but runs across the ground. This causes weathering of soil and rocks.

Chemical Weathering2. Chemical weathering – a process that

changes minerals in rocks. Crystal Ball Cave, Utah. Features hanging down from the ceiling are stalactites. Pillar-like features on the cave floor are stalagmites. Both stalagmites and stalactites are formed from the precipitation of limestone within the cave. Image courtesy of Dr. Ira Sasowsky.

ErosionErosion – the process of moving sediments

from one place to another.

Agents for erosion – Water, Wind, and Ice.

The Rock Cycle

The Rock Cycle

Click on the link below and learn more about

the rock cycle.

1. Play the movie.

2. Follow the directions given in the website.

http://www.classzone.com/books/earth_science/terc/content/investigations/es0602/es0602page02.cfm

Visit the Following Websites

http://duedall.fit.edu/wholeearth/geology_animations1.htm

http://walrus.wr.usgs.gov/seds/bedforms/animation.html

Bibliography

• http://www.uh.edu/~jbutler/physical/chapter6.html• http://3dparks.wr.usgs.gov/2005/naturalbridges/html/nb1

64.htm• http://pinker.wjh.harvard.edu/photos/new_zealand_II/ima

ges/Black%20Rocks%2004.jpg• http://www.cartage.org.lb/en/themes/sciences/

earthscience/geology/soils/FormationSoils/WeatheringSoils/ChemicalWeathering/chemicalweathering.htm

• http://earthnet-geonet.ca/glossary/display_term_e.php?term=erosion

• http://www.teachnet-lab.org/ps101/bglasgold/rocks/lesson3rockcycle.htm