1. Unit 1 CDA review answers

2. 1: State the 4 characteristics of a mineral
-naturally formed
-has a crystalline structure
-nonliving material--INORGANIC
-is a solid

3. 2:Describe the following properties used to identify minerals:
a. streak: the color of powder of a mineral when rubbed against a streak plate
b. luster: the way a mineral reflects light
c. cleavage: the splitting of a mineral along smooth, flat surfaces
d. fracture: the manner in which a mineral breaks along curved or irregular surfaces--jagged

4. 3: Why is it better to use the streak of a mineral instead of color when identifying minerals?
Many minerals are the same color. The mineral’s color can be affected by air or water while the streak will always be the true color of the mineral.

5. 4:Describe the Moh’s Scale of Hardness and list the minerals in order softest to hardest. Circle the softest and hardest minerals.
Moh’s Scale is a list of minerals listed in order from softest to hardest.
1: talc, 2:gypsum, 3:calcite, 4:fluorite, 5: apatite, 6: orthoclase, 7: quartz, 8: topaz, 9: corundum, 10: diamond

6. 5.How do we determine a mineral’s hardness?
By how easy or hard it is to scratch

7. 6: Explain the special properties of the following minerals:
a. calcite: fizzes with acid
b. halite: salty taste

8. 7.
_____Minerals____ make up _____rocks_________ but _____rocks_____ do not make up ____minerals____.

9. 8. How are rocks classified?
By how they form

10. Rocks broken down into small pieces or fragments
. 9: Define sediment.
Rocks broken down into small pieces or fragments

11. Compaction and cementation Conglomerate Sandstone Shale Coal limestone
. 10: For each type of rock, describe how they form and provided at least 2 examples of each
a.Sedimentary: COMPACTION AND CEMENTATION
How they form
Examples
sedimentary rock
Compaction and cementation
Conglomerate
Sandstone
Shale
Coal
limestone

12. b.Igneous: COOLING AND HARDENING OF MAGMA OR LAVA
How they form
Examples
intrusive igneous rock
Forms when magma cools and hardens below the Earth’s surface
Granite
Gabbro
extrusive igneous rock
Forms when lava cools and hardens on the surface
Basalt
Obsidian
Pumice

13. c. Metamorphic: HEAT AND PRESSURE
How they form
Examples
foliated metamorphic rock
Form from heat and pressure inside the Earth; minerals are arranged in bands or layers
Gneiss
Slate
nonfoliated metamorphic rock
Form from heat and pressure inside the Earth; minerals are NOT arranged in bands or layers
Marble
Quartzite

14. 11. What is a fossil? Why are they found in sedimentary rocks and not metamorphic or igneous rocks?
FOSSILS---any evidence of past life
Fossils are only found in sedimentary rocks because magma and lava would melt the fossil when an igneous rock formed and the heat and pressure would also destroy a fossil in a metamorphic rock.

15. 12:

16. 13: What is the difference between weathering and erosion?
Weathering breaks down rocks into smaller pieces called sediment and erosion transports the material from one place to another.

17. 14: Describe the following types of weathering
14: Describe the following types of weathering. Provide an example of each:
a.Chemical Weathering:
Occurs when rocks are broken down because of chemical reactions
EXAMPLES: acid precipitation (rain), lichens oxidation (rust)
b. Mechanical Weathering:
Happens when rocks are broken into pieces by physical means
EXAMPLES: ice wedging, tree roots, abrasion, burrowing animals

18. 14: c.Biological Weathering:
weathering or breaking down of rock by living things
EXAMPLES: lichens, tree roots, burrowing animals

19. 15. Define erosion
Movement of sediments from one place to another by wind, water, gravity, or ice.

20. 16. Based on the pictures of the two mountains below, which is the oldest? Explain your choice!!! You will need to use the terms weathering and erosion in your explanation.
The mountains on the left are the oldest. Since they have more rounded tops, you can tell that they have been weathered more over the years and erosion has transported the material away. The mountains on the right still have steep peaks at the top so they have not been weathered and eroded as much.

21. 17. Define deposition.
The process in which material is laid down
18. What is soil?
A mixture of small mineral pieces, organic material, water, and air
19. Define HUMUS.
Organic materials that form in soil from the remains of plants and animals

22. 20. Why are nutrients needed for healthy soil
20. Why are nutrients needed for healthy soil? Where do nutrients in the soil come from?
Nutrients in soil provide food for plants. These nutrients come from decayed organic material and poop.

23. 21. Deforestation is the process of removing/cutting down trees
21. Deforestation is the process of removing/cutting down trees. How does this increase soil erosion?
When trees are cut down, the roots of the trees are no longer able to hold soil in place and this allows erosion of the soil to increase.

24. 22. What is overgrazing? Is it good or bad for the soil? EXPLAIN
Overgrazing by animals causes soil erosion. The animals eat all of the vegetation which removes roots from the soil which hold the soil in place.

25. 23. Define soil conservation.
A method to maintain (save/keep) the fertility of soil by protecting the soil from erosion and nutrient loss.

26. 24. Why are cover crops important?
Cover crops are crops that are planted between harvests to replace certain nutrients and prevent erosion.

27. 25: Describe no-till farming.
A practice used by farmers of leaving old stalks in the garden which provides cover from rain and protection from soil erosion.