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Grade Level: 5 - 6
Purpose: To introduce glaciers to students and to allow
students to make the connection between glaciers and landforms.
Suggested Goals: Students will gain an understanding
of how glaciers are formed, how they move, and the landforms they create.
Targeted Objectives: As a result of this lesson students
will:
- Gain an understanding of how glaciers move
- Understand what types of landforms are created from glacial movement
Background: Glaciers are made up of fallen snow that,
over many years, compresses into large, thickened ice masses. Glaciers
form when snow remains in one location long enough to transform into ice.
What makes glaciers unique is their ability to move. Due to sheer mass,
glaciers flow like very slow rivers. Some glaciers are as small as football
fields, while others grow to be over a hundred kilometers long. Glaciers
made up most of the landforms that we have in Illinois including glacial
lakes, kettle lakes, till, and moraines.
Till is material that is deposited as glaciers retreat, leaving behind
mounds of gravel, small rocks, sand, and mud. It is made from the rock
and soil ground up beneath the glacier as it moves. Glacial till can form
excellent soil for farmland. Material a glacier picks up or pushes as
it moves forms moraines along the surface and sides of the glacier. As
a glacier retreats, the ice literally melts away from underneath the moraines,
so they leave long, narrow ridges that show where the glacier used to
be. Glaciers don't always leave moraines behind, because sometimes the
glacier's own meltwater carries the material away.
Streams flowing from glaciers often carry some of the rock and soil debris
out with them. These streams deposit the debris as they flow. Consequently,
after many years, small steep-sided mounds of soil and gravel begin to
form adjacent to the glacier. These mounds are called kames.
Kettle lakes form when a piece of glacier ice breaks off and becomes
buried by glacial till or moraine deposits. Over time the ice melts, leaving
a small depression in the land, filled with water. Kettle lakes are usually
very small and are more like ponds than lakes.
Glaciers leave behind anything they pick up along the way, and sometimes
this includes huge rocks. Called erratic boulders, these rocks might seem
a little out of place, which is true, because glaciers have literally
moved them far away from their source before melting away.
Materials/Preparation:
- Access to a freezer
- water
- cups
- dirt
- plastic tub or sink
- plaster of Paris*
- pictures of glaciers and landforms created by glaciers
- maps of Illinois
*Alternatives to plaster of Paris, although more expensive, include:
Activa Art Plaster, Crayola Model Magic, Direct’s Sculptamold.
Procedure:
- Have a discussion about what glaciers are, how they are formed, glacial
movement within Illinois, and what landforms glaciers create. Introduce
and discuss the terms kettle, moraine, lateral moraine, terminal moraine,
glacial lake, till, meltwater, kame, cirque, outwash stream, crevasse.
- Conduct an activity in which students build a glacier and observe
the effects of glacial movement. To do this, create a miniature glacier
by freezing gravel, sand or small rocks in a cup of water. Have the
students place the cup into the freezer over night. The next day they
should be able to tear the paper cup away and use the glacier to simulate
it’s movement over dirt, wood or other material. At the same time
they should be melting a pile of ice cubes on a mound of dirt so that
they can see the result of the melting glaciers on the land. It is important
to show actual photographs of what occurs so that students can make
connects to the larger life-size version of what they are seeing.
A suggested alternative is, rather than using individual ice cubes,
freeze water in a rectangular gallon container. Set up a stream table
with sand and start the “glacier” at one end by pushing
it into the sand. Set a lamp at the “south” end to simulate
global warming. As the day goes by, check the regress of the melting
“glacier.” River systems, lateral moraines, terminal moraines,
and glacial lakes should all develop. You can show the depression of
the Earth’s crust by putting a piece of play dough under the stream
table and allowing it to flatten. As the “glacier” melts,
the bottom of the stream table should rebound creating a gap in the
play dough.
- Have students build a plaster model of landforms created by glaciers.
- Have students label an Illinois map with glacial landforms.
Questions:
- What types of landforms do glaciers create?
- How do glaciers change the shape of the land?
- What effect have glaciers had in Illinois other than landform changes?
Extensions:
- Students can develop a presentation of the various landforms discussed
in this lesson.
- Move on to the “Landforms of Illinois” lesson
- Students can create paper models of glaciers. [Printable patterns
are available in the PDF download version of
this lesson.]
Assessment: Assessment of glacial models with labels
and the maps of Illinois. See rubric, "Building a Model" in
the PDF download version of this lesson.
Lesson Specifics:
- Skills: Observation, data collection. Computer skills are needed only
to access the Web site information.
- Duration:1 to 2 days
- Group size: Project may be completed individually or in groups of
3 or 4
- Setting: Classroom and computer lab with Internet access
Illinois State Board of Education Goals and Standards:
- 12.E.3b: Describe interactions between solid earth,
oceans, atmosphere and organisms that have resulted in ongoing changes
of Earth.
- 17.B.3a: Explain how physical processes including
climate, plate tectonics, erosion, soil formation, water cycle, and
circulation patterns in the ocean shape patterns in the environment
and influence availability and quality of natural resources.
- 26.B.3d: Demonstrate knowledge and skills to create
2- and 3- dimensional works and time arts (e.g., film, animation, video)
that are realistic, abstract, functional, and decorative.
Print Resources
Web Resources
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