Weathering, erosion and deposition: how land is worn down and built up

Grade 6 Science Worksheet - Challenge Me

Circle the best answer.

1. 1.

   On Esme's river map, P is the outside bank of a bend, Q the inside bank, and R a straight stretch. Over many years, which bank wears away most?

   • Both banks wear away equally
   • Q, on the inside bend, where sand piles up in a bar
   • Neither; banks change just in big floods
   • P, on the outside bend, where water is fastest
2. 2.

   Side view, not to scale. A dam slows a river into a long lake. Over many years, what does Kira predict builds up on the lake floor behind the dam?

   • Nothing; the dam stops erosion entirely
   • Less sand, since the water there moves faster
   • Sediment, dropped where the water slows
   • Weathered rock from the dam itself
3. 3.

   Luz's friend says weathering and erosion are two words for the same thing. Which response is best?

   • Disagree: weathering breaks rock; erosion moves the pieces
   • Agree: and water is the one agent for both
   • Agree: both words mean rock slowly wearing down over time
   • Disagree: erosion is when pieces are dropped
4. 4.

   A post claims only water shapes land, because wind is too weak to move rock. Milo checks it. Which response is best?

   • Agree: water does the shaping
   • Disagree: wind carries sand and builds dunes
   • Agree: wind can weather rock but cannot move it
   • Disagree: wind melts rock in deserts
5. 5.

   Steep, narrow, dark rock walls with the river at the bottom. Noah's cousin says a canyon as deep as the Black Canyon of the Gunnison could form within one person's lifetime. Which response is best?

   • Agree: one strong flood could carve it
   • Agree: rivers carve that deep in about a century
   • Disagree: the river began cutting it about 2 million years ago
   • Disagree: canyons form by deposition
6. 6.

   Gentle slope, 20 g of sand moved; medium slope, 45 g; steep slope, 80 g. Pia's class read about a stream-table test: the same water poured for 1 minute down sand at three slopes. What does the data show?

   • Slope makes no difference
   • Steeper slopes make the water drop more of its sand
   • The sand was weathered, not moved
   • Steeper slopes mean faster water and more erosion
7. 7.

   Tala's class shook sugar cubes in a closed, dry jar for 1, 3 and 5 minutes. The cubes got smaller and rounder each time. What does this model?

   • Deposition of sugar dust
   • Mechanical weathering by pieces rubbing together
   • The sugar dissolving in water
   • Erosion by wind in the jar
8. 8.

   Rain keeps washing soil off a bare slope beside Zee's school. Which plan would slow the erosion most?

   • Leave the slope bare so the rain can run off faster
   • Pile loose sand on top
   • Plant grass and shrubs whose roots hold the soil
   • Nothing; rain cannot move soil
9. 9.

   Waves keep carrying sand away from a town beach. Ari looks for an idea that works by slowing the water near shore. Which one?

   • A line of rocks offshore that breaks the waves
   • Removing the dune plants so sand can move freely
   • Speeding up the waves so sand settles
   • Digging the beach deeper
10. 10.

    Wind blows dry topsoil off a flat, bare farm field. Which plan does Bo pick to help most?

    • Water the field once a year
    • Nothing; wind cannot move soil
    • Plow the field bare and smooth so the dust settles
    • Plant rows of trees as a windbreak