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Geosciences LibreTexts

8.8: Student Responses

  • Page ID
    5616
  • 1. Sample I1 has what mafic color index (MCI)?

    a. 0-15% MCI

    b. 16-45% MCI

    c. 46-85% MCI

    d. >85% MCI

     

    2. Sample I1 has pink-colored minerals present, which are most likely _________.

    a. quartz

    b. biotite

    c. orthoclase

    d. Ca-rich plagioclase

     

    3. The small, dark-colored minerals in Sample I1 are most likely _________.

    a. quartz

    b. biotite

    c. orthoclase

    d. Na-rich plagioclase

     

    4. Sample I1 belongs to which igneous rock classification?

    a. ultramafic

    b. mafic

    c. intermediate

    d. felsic

     

    5. Sample I2 has what mafic color index (MCI)?

    a. 0-15% MCI

    b. 16-45% MCI

    c. 46-85% MCI

    d. >85% MCI

     

    6. Sample I2 belongs to which igneous rock classification?

    a. ultramafic

    b. mafic

    c. intermediate

    d. felsic

     

    7. Sample I3 has what mafic color index (MCI)?

    a. 0-15% MCI

    b. 16-45% MCI

    c. 46-85% MCI

    d. >85% MCI

     

    8. Sample I3 belongs to which igneous rock classification?

    a. ultramafic

    b. mafic

    c. intermediate

    d. felsic

     

    9. Sample I4 has what mafic color index (MCI)?

    a. 0-15% MCI

    b. 16-45% MCI

    c. 46-85% MCI

    d. >85% MCI

     

    10. Sample I4 belongs to which igneous rock classification?

    a. ultramafic

    b. mafic

    c. intermediate

    d. felsic

     

    11. Sample I5 has what mafic color index (MCI)?

    a. 0-15% MCI

    b. 16-45% MCI

    c. 46-85% MCI

    d. >85% MCI

     

    12. The white minerals in Sample I5 are most likely ______________.

    a. quartz

    b. biotite

    c. orthoclase

    d. plagioclase

     

    13. Sample I7 has what mafic color index (MCI)?

    a. 0-15% MCI

    b. 16-45% MCI

    c. 46-85% MCI

    d. >85% MCI

     

    14. According to Figure 8.1, Sample I4 will never contain which mineral?

    a. olivine

    b. pyroxene

    c. amphibole

    d. quartz

     

    15. According to Figure 8.1, Sample I7 must contain which mineral?

    a. olivine

    b. pyroxene

    c. amphibole

    d. quartz

     

    16. According to Bowen’s Reaction Series, Sample I5 (if heated) should start melting at what temperature?

    a. ~1100 °C

    b. ~900 °C

    c. ~800 °C

    d. ~500 °C

     

    17. According to Figure 8.1, when Sample I1 is heated, what is the first mineral to melt?

    a. olivine

    b. Ca-rich plagioclase

    c. potassium feldspar

    d. quartz

     

    18. Sample I1 has what texture?

    a. phaneritic

    b. aphanitic

    c. porphyritic-aphanitic

    d. glassy

     

    19. How did Sample I1 form?

    a. by magma that cooled slowly

    b. by fast cooling lava

    c. by a very fast cooling of lava

    d. by a very fast cooling magma during a volcanic eruption

    e. by magma that was cooling slowly, then as lava that cooled quickly

     

    20. Sample I1 is called______________.

    a. obsidian

    b. pumice

    c. granite

    d. rhyolite

    e. diorite

    f. andesite

    g. gabbro

    h. basalt

     

    21. Sample I1 can also be called ___________.

    a. volcanic

    b. plutonic

     

    22. Sample I2 has what texture?

    a. phaneritic

    b. aphanitic

    c. porphyritic-aphanitic

    d. glassy

     

    23. How did Sample I2 form?

    a. by magma that cooled slowly

    b. by fast cooling lava

    c. by a very fast cooling of lava

    d. by a very fast cooling magma during a volcanic eruption

    e. by magma that was cooling slowly, then as lava that cooled quickly

     

    24. Sample I2 is called______________.

    a. obsidian

    b. pumice

    c. granite

    d. rhyolite

    e. diorite

    f. andesite

    g. gabbro

    h. basalt

     

    25. Sample I2 can also be called ____________.

    a. volcanic

    b. plutonic

     

    26. Sample I3 has what texture?

    a. phaneritic

    b. aphanitic

    c. porphyritic-aphanitic

    d. glassy

     

    27. How did Sample I3 form?

    a. by magma that cooled slowly

    b. by fast cooling lava

    c. by a very fast cooling of lava

    d. by a very fast cooling magma during a volcanic eruption

    e. by magma that was cooling slowly, then as lava that cooled quickly

     

    28. Sample I3 is called______________.

    a. obsidian

    b. pumice

    c. granite

    d. rhyolite

    e. diorite

    f. andesite

    g. gabbro

    h. basalt

     

    29. Sample I3 can also be called __________.

    a. volcanic

    b. plutonic

     

    30. Sample I4 has what texture?

    a. phaneritic

    b. aphanitic

    c. porphyritic-aphanitic

    d. glassy

     

    31. How did Sample I4 form?

    a. by magma that cooled slowly

    b. by fast cooling lava

    c. by a very fast cooling of lava

    d. by a very fast cooling magma during a volcanic eruption

    e. by magma that was cooling slowly, then as lava that cooled quickly

     

    32. Sample I4 is called______________.

    a. obsidian

    b. pumice

    c. granite

    d. rhyolite

    e. diorite

    f. andesite

    g. gabbro

    h. basalt

     

    33. Sample I4 can also be called __________.

    a. volcanic

    b. plutonic

     

    34. Sample I5 has what texture?

    a. phaneritic

    b. aphanitic

    c. porphyritic-aphanitic

    d. glassy

     

    35. How did Sample I5 form?

    a. by magma that cooled slowly

    b. by fast cooling lava

    c. by a very fast cooling of lava

    d. by a very fast cooling magma during a volcanic eruption

    e. by magma that was cooling slowly, then as lava that cooled quickly

     

    36. Sample I5 is called______________.

    a. obsidian

    b. pumice

    c. granite

    d. rhyolite

    e. diorite

    f. andesite

    g. gabbro

    h. basalt

     

    37. Sample I5 can also be called __________.

    a. volcanic

    b. plutonic

     

    38. Sample I6 has what texture?

    a. phaneritic

    b. aphanitic

    c. porphyritic-aphanitic

    d. glassy

     

    39. Sample I6 has what composition?

    a. felsic

    b. intermediate

    c. mafic

    d. any of the above

     

    40. How did Sample I6 form?

    a. by magma that cooled slowly

    b. by fast cooling lava

    c. by a very fast cooling of lava

    d. by a very fast cooling magma during a volcanic eruption

    e. by magma that was cooling slowly, then as lava that cooled quickly

     

    41. Sample I6 is called_________.

    a. obsidian

    b. pumice

    c. granite

    d. rhyolite

    e. diorite

    f. andesite

    g. gabbro

    h. basalt

     

    42. Sample I7 has what texture?

    a. phaneritic

    b. aphanitic

    c. porphyritic-aphanitic

    d. glassy

     

    43. How did Sample I7 form?

    a. by magma that cooled slowly

    b. by fast cooling lava

    c. by a very fast cooling of lava

    d. by a very fast cooling magma during a volcanic eruption

    e. by magma that was cooling slowly, then as lava that cooled quickly

     

    44. Sample I7 is called______________.

    a. obsidian

    b. pumice

    c. granite

    d. rhyolite

    e. diorite

    f. andesite

    g. gabbro

    h. basalt

     

    45. Sample I7 can also be called ___________.

    a. volcanic

    b. plutonic

     

    46. Sample I8 has what texture?

    a. phaneritic

    b. aphanitic

    c. porphyritic-aphanitic

    d. glassy

     

    47. How did Sample I8 form?

    a. by magma that cooled slowly

    b. by fast cooling lava

    c. by a very fast cooling of lava

    d. by a very fast cooling magma during a volcanic eruption

    e. by magma that was cooling slowly, then as lava that cooled quickly

     

    48. Sample I8 is called______________.

    a. obsidian

    b. pumice

    c. granite

    d. rhyolite

    e. diorite

    f. andesite

    g. gabbro

    h. basalt

     

    49. Sample I8 can also be called ___________.

    a. volcanic

    b. plutonic

     

    50. Type the following coordinates into the search bar in Google Earth: 33 48 14.24 N 84 08 44.31 W. This is Stone Mountain, GA. Zoom in to an eye elevation of ~2400 ft for a closer look. Based on the color, and assuming no color change has occurred due to weathering at this location, what is the composition of rock?

    a. ultramafic

    b. mafic

    c. intermediate

    d. felsic

     

    51. Zoom out to an eye elevation of ~1500 ft so that you can see the entire mountain. Click on the ruler icon to open up the ruler function. Select the Line tab, and change the map length to kilometers. What is the longest length of the exposed portion of Stone Mountain?

    a. 3000 km

    b. 260 km

    c. 6 km

    d. 2.6 km

     

    52. Based on your measurement of the longest dimension, Stone Mountain can be classified as:

    a. a batholith

    b. a stock

     

    53. Type the following coordinates into the search bar in Google Earth: 64 58 45.54 N 16 43 07.04 W. Zoom in to an eye elevation of ~12979 ft for a closer look. Based on the color, what is the composition of this rock?

    a. ultramafic

    b. mafic

    c. intermediate

    d. felsic

     

    54. Zoom out to an eye elevation of 41,566 ft. Based on the proximity of the volcanic crater (now containing a lake), the igneous rocks identified in question 53 are:

    a. extrusive

    b. intrusive