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How weathering and erosion change the land

Science · Earth's Systems · ages 9-10

Name ______________________ Date ____________

Which term describes broken rock or soil being carried away to a new place?
- Erosion
- Weathering
- Melting
Which term describes rock breaking apart but staying in the same place?
- Erosion
- Weathering
- Evaporation
Wind can wear away rock over time.
Circle one: True False
Water enters a rock crack and freezes. What forms and expands, helping widen the crack?
- Ice
- Vegetation
- Wind
Adults supply records of a river bank. Which record would let a class check whether that bank retreated between two dates?
- A photo of that bank taken today
- Photos of two different banks from different viewpoints a year apart
- Photos of that bank from one viewpoint on two dates
At one marked point, a soil surface dropped 3 cm after one storm, 6 cm more after the next, and 9 cm more after the third. What was the total drop, in centimeters?
Answer: ______________
Dated photos from the same viewpoint show a cliff retreating over 20 years. Observers also record cracks widening and water carrying loose pieces away. What does the combined evidence support?
- New rock was added at the cliff edge throughout the 20 years
- The cliff stayed unchanged and no loose pieces moved during the 20 years
- Weathering and erosion changed the cliff over time
A model's soil surface is lower after rain. Sam says all the drop must be erosion. Which check would best test his claim?
- Treat the lower surface alone as proof that soil moved
- Look for soil transport and check for soil being pressed down
- Use the rainfall amount alone to decide how much soil moved

Answer key

For grown-ups. Fold this page away before handing over the rest.

How weathering and erosion change the land W1-mt_vAP_A986IQ-s1

Erosion · Erosion is the movement of broken rock and soil from one spot to another.
Weathering · Weathering breaks rock down right where it sits. It doesn't move the pieces anywhere.
True · Wind blows tiny grains of sand against rock, slowly wearing it smooth.
Ice · The water becomes ice. Expansion as it freezes can push against the crack's sides.
Photos of that bank from one viewpoint on two dates · Photos of the same bank from the same viewpoint on two dates let the class compare its position. One photo or pictures of different banks do not provide that comparison.
18 · Add the three separate drops at the same point: 3 + 6 + 9 = 18 cm.
Weathering and erosion changed the cliff over time · Widening cracks show weathering. Water transporting pieces shows erosion. The dated photos show the cliff changing over time.
Look for soil transport and check for soil being pressed down · A lower surface could result from soil moving away or being pressed down. The surface reading alone does not separate these causes.