Grade 8 · Science · Unit 20 of 22
Waves, Streams & Glaciers
How moving water and ice shape the land
What your child practises
How water and ice wear away and rebuild land, what causes waves and tides, how streams and deltas form, what ocean basins look like, and how ocean currents affect climate.
Alberta Curriculum learning outcome: Unit E: Freshwater and Saltwater Systems · erosion and deposition by waves, streams and glaciers, tides, ocean basins and ocean currents
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
On a river bend (meander), where does the water erode the most?
- on the outside of the bend
- nowhere
- on the inside of the bend
- exactly in the middle
Show answer
on the outside of the bend
Hint: Water moves fastest on the outside, so it wears the bank away there and drops sediment on the inside.
Question 2
Erosion or deposition? Sort each example.
Sort into: 🌊 Erosion · 🏖️ Deposition
- 🏝️waves pile sand onto a beach
- 💦a spring flood carries away riverbank soil
- 🧊a glacier scrapes a valley
- 🏖️a sandbar forms in a calm bend
- 🌾a delta builds up at a river mouth
- 🪨silt settles in a quiet lake
- 🌊waves wear away a cliff
- 🏞️a river cuts a deep canyon
Show answer
🌊 Erosion: a spring flood carries away riverbank soil, a glacier scrapes a valley, waves wear away a cliff, a river cuts a deep canyon · 🏖️ Deposition: waves pile sand onto a beach, a sandbar forms in a calm bend, a delta builds up at a river mouth, silt settles in a quiet lake
Hint: Erosion wears away and carries material off. Deposition drops material in a new place.
Question 3
Which feature is found on the ocean floor?
- a deep trench
- a sand dune
- a tall glacier
- a prairie
Show answer
a deep trench
Hint: Ocean basins have shelves, slopes, trenches and ridges.
Question 4
What is erosion?
- the wearing away and moving of rock and soil
- the dropping of material in a new place
- the building of a dam
- the freezing of water
Show answer
the wearing away and moving of rock and soil
Hint: Water, wind and ice can wear down land and carry material away.
Question 5
The Columbia Icefield is shrinking. What is the most likely reason?
- More snow is falling than ever.
- People are carrying ice away by hand.
- The Sun is moving away.
- Warmer temperatures are melting more ice than the snowfall adds.
Show answer
Warmer temperatures are melting more ice than the snowfall adds.
Hint: A glacier shrinks when it loses more ice than it gains.
Question 6
What is a delta?
- a mountain
- land built up from sediment where a river meets a larger body of water
- a kind of fish
- a deep ocean trench
Show answer
land built up from sediment where a river meets a larger body of water
Hint: When a river slows down at its mouth, it drops its sediment.