earth science- midterm 1

1. Diamond and graphite are formed as a result of different types of carbon

Bonding

2. The earths magnetic field is generated by the

Outer core

3. What is the approximate age of earth

4.6 billion

4. Which of the following about scientific theory is not true

It is a conjecture or guess

5. The earths outer most rigid layer is called

Lithosphere

6. The mood formed due to the protoplant colliding with the earth about 4.5 million years ago

False (billion)

7. Lithospheric plates collide during divergent boundaries

False ( convergent)

8. Which one of the following is not a characteristic of a shield volcano

large explosive pyroclastic eruption

9. Low viscosity volcanoes tend to have___ Sio2

Content and ____ flows

Low and fast

10. Will Giove you pictures determine the volcanic structure

    pillow

Pahoe hoe

11. Baaltic lava have high viscosity whereas rystosa have

Incorrect

12. Which of the following mineral pairs are the most abundant in basalt?

    Plagioclase and pyroxene

13. Basalts typically have a/an...

    Aphanitic

14. Fast cooling of magmas tends to produce an aphanitic texture

True

15. Phenocrysts in a porphyritic texture reflect fast cooling

false

16. Basalts are the most common intrusive rocks on Earth

false

17. Glassy textures are product of lower nucleation and higher growth rates than aphanitic textures.

false

18. Phaneritic textures are product of lower nucleation and higher growth rates than aphanitic textures.

true

19. What kind of igneous texture is shown in the photo graph ( grey rock, with black pebbles all over them)

pyroclastic

20. What kind of igneous texture is shown in the photo graph ( grey rock with white pebbles in graved, all different sizes covering it)

porphyritic

21. The properties of minerals (e.g., color, streak, luster, etc.) are an indication of the crystal

    _____and chemical____

??

22. Which class represents most minerals?

    Silicates

23. What is the name for a plane where a mineral tends to split sue to weaker bonds?

    Cleavage plane

24. In a covalent bond

    (c) Electrons are shared between all atoms in a solid mass

25. Which pair of the following minerals do represent the softest and hardest mineral on the Mohs' hardness scale?

    Talc and diamond

26. Colour is one of the most diagnostic physical properties of minerals

    False

27. which pair of the following chemical formulas do represent —erite-olivine and quartz?

    NaCl and CaCO3

28. which paire of the following chemical formulas do represnt Nayalite-olivine and calcite?

    Fe2SiO2 and CaCO3

29. What is the most abundant mineral in the crust?

    Pyrozene

30. Which pair of the following chemical formulas do represent albite and anorthite plagioclase?

    (a) NaAISi,0g and Mg,SiO,

    (6) Fe,SiO, and KAlSI38

    (c) NaAISi,Og and CaAl2Si2O8

    (d) NaCl and CaCO3

    (e) CaAl2Si208 and KAISi308

31. Chondrites are the oldest known rocks in the solar system?

    T or F

32. Acoording to the following diagram, the granite pluton is older than the fault

True

33. If an isotope has a half-life of 100 million years, what would be the parent to daughter ratio in 200 million years.

(a) 4/1

(b) 3/1

(c) 1/4 (d) ½

(e) 1/3

34. If a newly formed mineral has 2000 radioactive parent isotopes and zero daughter isotope, what would the parent/daughter isotope ratio be after three half-life times

1/7

35. If a mineral has 1200 radioactive parent isotopes, how many parent isotopes will remain after 3 half life times?

150

36. If the nucleus of an isotope (eg. 20^x) captures four electrons, how would its proton number change?

Decrease four

37. If the nucleus of an isotope (eg. 60^x) undergoes four alpha decay, how would its proton number change?

decrease eight

38. If the nucleus of an isotope (eg. 60^x) undergoes two alpha decay, how would its proton number change?

decrease eight

39. According to the following diagram, the sill is older than the sandstone (#5) layer

true

40. The process where new seafloor is created at mid-ocean ridges, moves away from the ridges, and then subducts back into the mantle is called.

    Sea-floor spreading

41. Glaciers have higher 18^O/16^O ratios than seawater

false

42. Does a negative magnetic anomaly form when the seafloor rock polarity is the same as the present magnetic field?

No

43. Who was the first scientist to propose the continental drift hypothesis?

Alfred Wegener

44. The plate boundry between the Andes and the Pacific ocean is an example of

Convergent boudry

45. What is the name of all the landmasses, proposed by Alfred Wegener, that were united into the supercontinent about 300 million years ago

pangea

46. Which one of the following lists do represent the youngest to the oldest magnetic epochs (chrons)

Brunches, Matuyama, Gauss, Gilbert

47. Earths magnetic poles regularly reverses every 1.5 million years as documented along mid-ocean ridges

False

48. Magnetic inclination angles vary along the latitude lines

False

49. Magnetic inclination angle measurements indicate that they are highest at the equator

False

50. In seawater 18^O/16^O increases during the ice ages

true

51. Seawater has lower 18^O/16^O ratios in rain water

false

52. Mantle plumes originate below the lithossphere

True