Define weathering, regolith and soil.
How does the process of weathering relate to the product of soil?
Explain why the earth is the only planet in our solar system with substantial amounts of soil.
Provide two examples of weathering that you have observed.
Define mechanical (Physical) and chemical weathering
Briefly explain the differences between mechanical and chemical weathering
How does mechanical and chemical weathering work together to weather down earth material?
Which has more impact on earth features — mechanical or chemical weathering. Explain your answer
Below are three common types of mechanical (Physical) weathering processes pointed out in lecture. Describe each process in your own words and provide a picture (hand drawn).
Does chemical weathering affect the above mechanical weathering processes? How, explain.
How does frost wedging affect Mt. Rushmore?
Given the geologic environment for the formation of granite, why is it typical for granite to “unload” or exfoliate when exposed to the surface.
Provide an example where humans contribute to mechanical weathering.
5. Chemical weathering breaks down rock material producing a “new” chemical compound or another type of rock
Explain why rocks on the earth’s surface are chemically altered — in other words, why don’t rocks just stay the same?
What is the most common chemical agent on earth that begins the chemical breakdown of rocks or anything else this agent comes in contact with?
How does CO2 in the atmosphere increase the chemical weathering force of this common chemical agent?
6. In lecture, we discussed the action of water, as the universal solvent, that chemically breaks down rock. We used the chemical reaction between water, carbonic acid to chemically alter the orthoclase mineral into kaolinite clay.
Using your ppt notes and lecture, write the chemical reaction that converts orthoclase into kaolinite clay
Explain what the conversion from orthoclase to clay does to the granite rock
Given the chemical reaction, how is granite a plant fertilizer??? Interesting question.
How can chemical weathering of a granite tell the geologist the granite is old or young?
7. Clay is regarded as the “end product” of chemical weathering? See the chemical weathering slide that shows various types of rocks weathering or reducing to various clay compounds.
Explain why clay is the last end product of chemical weathering
Do you think the rate of chemically altering rocks into clay is fast or slow? Explain
What do clay deposits tell the geologist about relative ages of layers of rock?
8. What’s in your soil? See the “what’s in your soil” slide and write down the constituents that make a soil.
Use the soil ternary diagram and provide 3 examples of your own soil classifications— in other words, learn how to determine a soil classification using the sand, clay and silt particle sizes.
How is the term “loam” used to classify a soil?
Given the components of a soil, why is it important for a soil to have concentrations of C02 and water.
9. Access the soil profile slide where it shows a “typical” soil profile.
Draw and provide a diagram that depicts the typical soil profile — basically copy the soil profile and label each horizon with its physical properties
Why would it be logical for organic material (humas) to concentrated at the top of a profile
How does the presence of CO2 and water influence horizons A and E?
How would one explain the existence of horizon B (clay) towards the bottom of the profile?
What does horizon C (weathered bedrock) indicate about the soil profile? the this soil profile considered emplaced or has it been transported (explain)
10, In the lecture, it’s pointed out that many physical factors influence the development of soil profile. After viewing the factors affecting soil profiles, summarize and write down each factor that influences a soil profile.
Given the factors influencing soil profile formation, do you think there are several types of soil profiles found on earth or a small amount soil profiles, explain your answer.
What factor influencing soil profile formation do you think is dominant? Explain your answer
Why would soil profiles tend to be thicker in basin type structures?
What would a well-developed soil profile tell a field geologist?
Given these influencing factors, what type of soil profile would expect in your backyard, or the San Joaquin Valley?
11. What is soil taxonomy?
How would you describe the “taxonomy” or breakdown of soil classification?
Observing the basic “order” of soils, write down all 12 orders. Be prepared to match the soil classification name with the type of soil for the exam.
Which soil order is classified for the San Joaquin Valley — Why?
Observing the global distribution of soils, what is the major factor that influences soil formation?
Possible Essay Questions for this section
Describe the differences between mechanical (physical) and chemical weathering and provide two examples of each.
Describe the horizons that develop in a typical emplaced soil profile and the relationship to mechanical and chemical weathering processes.