Rocks, Weathering and Erosion Quiz Review

1. Draw and label the rock cycle below. Include the following:

a. The three major rock types

b. Sediment and magma

c. Arrows labeled with the processes of melting; cooling and crystallizing; weathering and erosion; deposition and cementation; intense heat and pressure.

2. Using complete sentences, explain the difference between intrusive and extrusive igneous rocks. Discuss where each is formed, how it cools, and what types of grains are associated with each. Finally, GIVE AN EXAMPLE OF EACH.

3. Classify each of the following as either a mineral, a rock or an ore.

a. Calaverite is composed of tellurium and gold. It is mined for to produce valuable jewelry.

b. Albite is a type of feldspar that crystallizes in nearly right angle prisms. Commonly found in many types of rocks, it is the most common type of feldspar.

c. Basalt is often found in flows near volcanoes. It is dark and contains small air bubbles in places where gas was trapped in the cooling magma.

4. Explain which resource is more economically viable for extracting aluminum (Al), the ore bauxite Al(OH)₃ or the recycled aluminum alloy Al₃SC. (HINT: Use the atomic weights like we did with the Cookie Mining Lab).

5. What is the difference between weathering and erosion?

6. What are the two main types of weathering?

7. How is chemical weathering different than physical weathering?

8. Identify four types of physical weathering and two types of chemical weathering.

9. Identify and explain four types of erosion processes.

10. Explain why the Grand Canyon is so deep?

11. Explain why the Grand Canyon is so wide?

12. Which type of weathering creates distinctive v-shaped valleys?

13. Which type of weathering creates distinctive u-shaped valleys?

14. What type of rock is granite? How is it formed?

15. What type of rock is shale? How is it formed?

16. What type of rock is slate? How is it formed?

17. What type of rock is sandstone? How is it formed?

18. What type of rock is marble? How is it formed?

19. What type of rock is limestone?

20. Why is the statue of Liberty green?

21. What is the difference between alpine glaciers and continental glaciers?

22. Explain deposition and cementation.

23. How are the rates of weathering and erosion affected by climate?

Chemical Weathering Review

Alpine Glacial Erosion Review

Reading: Due Friday 4/22

Read the three articles and answer the questions below.

Scientist at Work: Volcanic Rocks Just North of the Border

Scientist at Work: Into a Lunar Training Ground

Scientist at Work: The Mars Connection

1. How does Marlow describe Geology in relation to other sciences?
2. The article describes Lauren as a sedimentologist. What does she study and why is this important?
3. Initial investigators thought that Kilborne Hole may have been formed by a meteor. Describe what Geologists now believe caused this formation.
4. What types of flows can create crossbedding in rocks?
   
5. How are lapilli and volcanic bombs formed?
6. Small spherical rocks containing the mineral hematite are found on both Mars and Earth. However, scientists believe that these rocks were formed in different ways. How do Geologists believe the formation of "blueberries" on mars differs from the formation of lapilli spheres in the base surge deposits?

• Hint for 6: Read more about "blueberries" here. http://phoenix.lpl.arizona.edu/mars153.php
  

Rates of Weathering

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¹ As dramatic as the process of weathering sounds, it does not happen overnight. In fact, some instances of mechanical and chemical weathering may take hundreds of years. An example would be the dissolving of limestone through carbonation. Limestone dissolves at an average rate of about one-twentieth of a centimeter every 100 years. If you want to see a layer of limestone (about 150 meters thick) dissolve, plan on watching that layer for about 30 million years.

² Where we see the effects of weathering often is on our stone monuments and buildings and large rock structures. However, before you can analyze the rate at which these structures are weathering, you need to understand the factors that affect weathering rates. The weathering rate for rocks depends on the composition of the rock; the climate of the area; the topography of the land; and the activities of humans, animals, and plants.

³ A rock's composition has a huge effect on its weathering rate. Rock that is softer and less weather-resistant tends to wear away quickly. What is left behind is harder, more weather-resistant rock. This process is called differential weathering. Quartz is one type of rock whose composition, especially its crystalline structure, makes it resistant to mechanical and chemical weathering. This is why quartz remains unchanged on the Earth's surface after surrounding sedimentary rock has been eroded. There are some rocks, like limestone, that weather more rapidly. Limestone has the compound calcite. It is the carbonization of calcite that causes the increased rate of weathering of limestone. The material found in sediment grains also affects the rate of weathering. The mechanical weathering of rocks like shale and sandstone causes their grains to break up over time and become sand and clay particles. Why? Well, the grains in these two types of rocks are not cemented together firmly. Rocks like conglomerates and sandstones have grains that are cemented strongly with silicates. These rocks and other similar types tend to resist weathering. Geologists have also found that they may resist weathering longer than some types of igneous rocks.

⁴ A rock's exposure to the weathering elements and its surface area can affect its rate of weathering. Rocks that are constantly bombarded by running water, wind, and other erosion agents, will weather more quickly. Rocks that have a large surface area exposed to these agents will also weather more quickly. As a rock goes through chemical and mechanical weathering, it is broken into smaller rocks. As you can imagine, every time the rock breaks into smaller pieces its surface area or part exposed to weathering is increased. Think about a cube, which has both volume and surface area. To find the surface area of a cube, you need to calculate the sum of the areas for all six sides. Let this cube represent our rock that is exposed to weathering. Already our cube has six sides that are exposed to the elements. If we split our cube into eight smaller cubes, then the total surface area would be doubled. Although the surface area increases, the volume remains constant. Splitting the eight smaller cubes in the same way would have the same effect; the surface area would again be doubled. Increased surface area causes rocks to weather more rapidly.

Follow Up Questions

1. Which factors affect the rate of weathering?
2. Explain the concept of differential weathering in your own words.
3. Explain how exposure affects the rate of weathering.
   

Take this quick quiz to test your knowledge:
http://glencoe.mcgraw-hill.com/sites/0078617529/student_view0/chapter2/section1/self-check_quiz-eng_.html

Weathering Lab Follow Up

Lab 1 – Carbonated Water with Rocks

· What does the carbonated water approximate in the real world?

· What type of weathering does this model?

Lab 2 – Vinegar and Copper Pennies

· What does the vinegar approximate in the real world?

· What does the copper penny approximate?

Lab 3 – Antacid Tablets in Water

· What type of weathering did you approximate by smashing one of the tablets?

· How did smashing the tablet affect the rate of weathering?

· How does this relate to the weathering of rocks?

Lab 4 – Vinegar and Chalk

· What does the chalk represent in the real world?

· What does the vinegar approximate in the real world?

· What type of weathering does this model?

Lab 6 – Tap Water and Steel Wool

· What does the steel wool approximate in the real world?

· What type of weathering does this model?

Lab 7 – Shaking Sugar Cubes/Rocks

· What type of weathering was modeled by shaking the jars?

· Why did one substance “weather” more than the other?

· What could this mean for the rate at which different types of rocks weather?

Interactive Rock Cycle Review

Visit the link below to review the rock cycle and rock types. Print of your test when you are finished.

http://www.learner.org/interactives/rockcycle/

Visit this link to review some common types of rock. If you're having a really hard time identifying the rocks, read the background information listed below under "Common Rocks and Minerals."

http://www.kidsgeo.com/geology-games/rocks-game.php

Common Rocks and Minerals

Igneous:

• granite
• basalt
• 0bsidian
• pumice

Metamorphic

• slate
• schist
• marble

Sedimentary

• chalk
• coal
• sandstone
• shale
• limestone

Minerals

• quartz
  
• magnetite
  
• graphite
  

Water Unit Quiz Review

Materials to Review

• "Calculating Earth's Water Distribution" - mini Lab/worksheet
  
• "Water Use Background Reading" - reading/questions
• "Notes: Earth's Water and Water Cycle" - notes/worksheet
• "Portland's Water" - blog/worksheet
• "Household Water Consumption Reflection" - worksheet
• Student Presentations: Global Water Crisis - notes

Key Terms/Concepts

• consumption
• degradation
  
• polar vs. non-polar substances
• renewable water supply
  
• solubility
• turbidity
  
• watershed
• water reservoir
  
• water stress
• withdrawal
• water cycle

Mark You Calandar: World Water Day 3/22/11

World Water day is quickly approaching on the 22nd of March. We will be gone on spring break, but that doesn't mean you can't participate. Visit the World Water Day website to find out about events across the globe.

http://www.unwater.org/worldwaterday/index.html

If you will still be in Portland on the 22nd, then check events for the city. You are invited to invited to participate in the third annual Walk for Water on Sunday, March 27, 2011 at 1 p.m. at the World Trade Center, located at SW First and Salmon Streets in downtown Portland.

http://www.worldwaterdaypdx.com/

Here's a Video from the 2010 Walk for Water.