EARTH SYSTEMS 2 ND SEMESTER FINAL EXAM REVIEW GUIDE 2012-2013

1. EARTH SYSTEMS2ND SEMESTERFINAL EXAM REVIEW GUIDE2012-2013

2. What events warn scientists that a volcanic eruption may occur?

3. 1.) changes in earthquake activity near or around the volcano such as an increase in the strength and frequency of the earthquakes 2.) temperature changes in the rock and soil surrounding a volcano 3.) the upward movement of magma beneath the surface may cause the surface of the volcano to bulge outward 4.) changes in the amount and composition of the gases that the volcano emits

4. What are the three primary topographical land tectonic settings?

5. 1.) convergent/divergent tectonic plates 2.) subduction zones -trench -island arc 3.) mid-ocean ridge

6. What is the difference between a pluton and a batholith?

7. Magma that pushes up can cause fissures or fractures that can be skinny lines or huge fat formations. Magma that does not reach the Earth’s surface, then cools and solidifies is called a pluton. Small plutons are dikes, and large plutons are batholiths. What is an example of a batholith in Georgia?

9. What is an example of an exposed batholith?

10. Stone Mountain

11. Where is the most active site of volcano and tectonic activity on Earth?

12. Pacific Ring of Fire

13. What are the fragments of rock that are spit from a volcano and includes large and small pieces of volcanic ash, dust, lapilla, bombs, and blocks?

14. pyroclastic material

15. How are most volcanic islands formed?

16. Most island volcanoes are made or formed of mafic magma. Because of the magma’s low viscosity, they are the result of quiet eruptions. Mafic magma is magma rich in magnesium and iron and is commonly dark in color. Felsic magma is made of light- colored silica materials. Mafic rock commonly makes up oceanic crust and felsic and mafic rock together usually make up continental crust.

17. What are the conditions that affect whether magma forms?

18. Magma forms when the temperature of the rock rises above the melting point of the minerals that compose it. Also, the pressure of the rock lessons or decreases faster than its temperature does. And, when it is mixed with fluids that decrease it’s melting point.

19. What happens when an ocean plate and a continental plate collide?

20. The oceanic plate is likely to subduct because it is more dense than the continental plate.

21. What causes rock in the lower mantle to remain below its melting point?

22. Both temperature and pressure increase as depth below Earth’s surface increases. This keeps rock at the core hot and liquid.

23. Explain how magma reaches Earth’s surface.

24. Both temperature and pressure increase as depth below Earth’s surface increases. This keeps rock at the core hot and liquid.

25. How does the amount of a rock’s surface area affect weathering?

26. The larger the area, the higher the rate of weathering.

27. Plant and animal activities cause what kind of weathering?

28. chemical and mechanical Weathering Chemical weathering is when rocks break down as a result of chemical reactions such as the formation of caves or iron rusting. Mechanical weathering is when rocks break down by physical means such as freezing and thawing and salt wedging.

29. Climates that have the fastest rate of weathering are what?

30. Alternating hot and cold temperatures

31. Topography with high mountains and steep slopes are especially vulnerable to what type of weathering?

32. mechanical weathering

33. Which landform is NOT the result of weathering and erosion?

34. wetlands

35. Which farming methods conserve or save soil?

36. Contour plowing – plowing the land in contours or curves that follow the shape of the land preventing water from flowing down hill and causing gullies to form • Strip-cropping – alternating cover crops side by side with food crops preventing runoff • Terracing – constructing step-like ridges that follow the contours of the land preventing runoff • Crop rotation – the planting of different crops each year preventing the depletion of nutrients the soil needs to be healthy for plants Furrowing is does not help soil. It is the old fashioned way of using a tool like a plow to dig a trench.

37. What effect would you expect a drought to have on the capillary action in soil and, ultimately, on your supply of fresh groundwater?

38. Without rainwater to replenish aquifers, the capillary action will slow and then stop as the water table drops and then dries. The result is a dry well and no water. Conservation of groundwater is critical during times of drought in order to prevent total depletion of the water supply.

39. How does gravity affect the flow of groundwater?

40. Water flows downward in response to gravity. The rate at which it flows depends on the permeability of the rock and the gradient. The greater the permeability of the rock, the faster the water will flow. The velocity of the flow responds to gravity and increases as the gradient increases.

41. Rock becomes chemically weathered when what happens?

42. When carbonic acid, formed when water passes through soil, dissolves minerals in the rock, then rock becomes chemically weathered?

43. Which minerals make rocks especially vulnerable to chemical weathering?

44. calcite • The mineral calcite is composed of calcium, carbon, and oxygen. The chemical formula is CaCO3.

45. A cavern is a natural cavity in rock that forms as a result of what?

46. the dissolution of minerals or minerals washed out from inside the Earth

47. How does a river form?

48. Precipitation or rainfall exceeds evapotranspiration. • Soil soaks up as much water as it can hold. • Excess water erodes the land, and eventually a river valley forms.

49. What are two ways that fresh water supplies can be maintained?

50. water conservation methods • alternative methods of obtaining fresh water