Four Winds Nature Institute
4 Casey Rd. Chittenden, VT 05737
802-353-9440
www.fourwindsinstitute.org
WEATHERING & EROSION – SLIDE SHOW SCRIPT
1. BRYCE CANYON NATIONAL PARK, UTAH:
The landscape around us is constantly changing shape, sometimes fast but often so slowly that we never even
notice it. Still, the processes of erosion and weathering can create dramatic effects. In Bryce Canyon, Utah, water
and ice have carved the colorful limestone, creating these beautiful towers and spires.
2. GRAND CANYON, ARIZONA:
In the Grand Canyon, rain and water have cut through thousands of feet of earth, exposing layer upon layer of
rock. Each layer tells a story of how the landscape has been shaped over time.
3. RAIN:
It’s hard to imagine that raindrops can carve a canyon, but it’s true! Raindrops can start the process of erosion by
splashing on a surface, breaking away tiny particles and carrying them off.
4. GULLIES:
As raindrops hit the ground, loose soil is splashed in every direction. Water collects and moves downhill, often
making gullies that can get larger and larger and…
5. WASH OUT:
…sometimes produce large trenches. What has happened here? (A roadway has been washed out) This is erosion,
the process by which particles of rock or soil are loosened and carried away.
6. MOUNTAIN STREAM:
When lots of raindrops work together, the results are truly impressive. Fast moving water in a stream can be a
powerful agent of erosion. It wears away rock and moves soil as it flows downhill.
7. QUECHEE GORGE:
Over time, stream flow can carve out a deep gorge like this one. When rivers cut down through rock and soil, they
create deep, v-shaped valleys that are quite narrow at the bottom, like this view of the Quechee Gorge in eastern
Vermont.
8. GLACIAL VALLEY (Iceland):
The U-shape of this broad valley tells us that it was not formed by the cutting action of a river. It was created by
another agent of erosion…
9. ALASKA GLACIER:
…A glacier! Glaciers are massive sheets of snow and ice, some the size of mountain ranges! Big, heavy, and
slow-moving, glaciers scrape and crumble rock, shaping mountains, carving out valleys, and leaving behind piles
of gravel and stone. Just imagine, 12,000 years ago New England was buried beneath a glacier over a mile thick!
10. GLACIAL ERRATIC: As a glacier retreats, chunks of rocks, sand and anything else that has been dragged
along with the glacier drop out. Occasionally we find large boulders looking very out of place in the middle of a
field. Glaciers left these behind thousands of years ago. Is there evidence of past glacial erosion near where you
live? (Big, rounded rocks, stones and boulders in the landscape, u-shaped mountain valleys or gravelly ridges.)
11. ROCKY SHORE:
Ocean waves crashing against a rocky shore will erode rock, breaking it down into boulders, rocks and eventually,
over a long period of time, particles of sand.
© Copyright Four Winds Nature Institute
12. SAND DUNES (Oregon):
Like water, wind can also wear away rock and shape the landscape as it picks up and carries soil and sand. Beach
sand may be blown into dunes along sandy shores.
13. DOUBLE ARCH, ARCHES NATIONAL PARK, UTAH:
Blasting by wind-borne sand and erosion by rain can create incredible formations like the Double Arch in Arches
National Park, Utah.
14. MUD SLIDE:
Sometimes, erosion can be a sudden and dramatic event like this mudslide. Often these occur after several days of
heavy rain, when water-saturated earth speeds down a steep slope. Gravity is a powerful agent of erosion.
15. JAGGED MOUNTAIN PEAKS:
Yes, our landscape is always changing. Old mountains are being worn down in some places on Earth, while new
mountains are being pushed up in others. Do you think these are older or newer mountains? (Fairly new – still
jagged, not smoothed by weathering and erosion.)
16. GREEN MOUNTAINS:
Low, rounded hills covered with forest look very different than the jagged rocky peaks. Do you think these are
young or old mountains? (Very old, they’ve been worn down by erosion, weathering and ice ages)
17. BAKER PEAK, GREEN MOUNTAIN NATIONAL FOREST:
Baker Peak, part of what was once a much higher ridge in the Green Mountains, has been smoothed and shaped
over time by wind, rain, ice, and snow.
18. HOUSE PERCHED ON DUNE:
Grain by grain and year by year, the process of erosion turns hard rock into soil and moves soil from one place to
another. Human activities like road work, building construction, and farming may cause erosion, and sometimes
that process threatens our houses, farms or roads.
19. RETAINING WALL:
Humans have come up with many ways to try to slow the flow of soil. A cement or stone retaining wall is one
approach.
20. EROSION MITIGATION
We may also build banks of heavy stone, lay out silt fence, or plant grass or trees to help hold onto the soil.
21. GREEN MOUNTAINS VIEW (Middlebury, VT):
The processes of erosion and weathering are powerful ones. Even though at times we may struggle against them,
these natural processes shape the landscapes that we call home.
Four Winds Nature Institute – 7/11.
© Copyright Four Winds Nature Institute