For each question below, choose the letter corresponding to the BEST answer.
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1 | |
A surface separating different types of rocks is called:
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| | A) | a chill zone. |
| | B) | a xenolith. |
| | C) | a contact. |
| | D) | none of the above |
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2 | |
The major difference between intrusive and extrusive igneous rocks is:
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| | A) | the type of minerals they contain. |
| | B) | where they solidify. |
| | C) | their chemical composition. |
| | D) | all of the above |
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3 | |
Which is not an intrusive rock type?
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| | A) | andesite |
| | B) | granite |
| | C) | diorite |
| | D) | gabbro |
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4 | |
By definition, stocks differ from batholiths in:
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| | A) | elevation above sea-level. |
| | B) | chemical composition. |
| | C) | shape. |
| | D) | size. |
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5 | |
On average, the geothermal gradient is about:
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| | A) | 50 degrees Celsius per kilometer. |
| | B) | 30 degrees Celsius per kilometer. |
| | C) | 10 degrees Celsius per kilometer. |
| | D) | 1 degree Celsius per kilometer. |
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6 | |
Which of the following minerals is part of Bowen's Continuous Series?
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| | A) | plagioclase. |
| | B) | amphibole. |
| | C) | biotite. |
| | D) | pyroxene. |
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7 | |
Which of the following minerals is part of Bowen's Discontinuous Series?
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| | A) | olivine |
| | B) | biotite |
| | C) | pyroxene |
| | D) | All of these are part of Bowen's Discontinuous Series. |
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8 | |
The difference in texture between plutonic and volcanic rocks is caused by:
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| | A) | different chemical compositions. |
| | B) | different amounts of water in the magma. |
| | C) | different rates of cooling and crystallization. |
| | D) | different mineralogy. |
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9 | |
A change in magma composition due to melting of surrounding country rock is called:
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| | A) | differentiation. |
| | B) | crystal settling. |
| | C) | assimilation. |
| | D) | magma mixing. |
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10 | |
Andesite is most often associated with what type of plate boundary?
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| | A) | reversible plate boundaries |
| | B) | convergent plate boundaries |
| | C) | transform plate boundaries |
| | D) | divergent plate boundaries |
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11 | |
You discover a rock with minerals large enough to be seen containing amphibole, biotite, and plagioclase. This is:
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| | A) | hornblende. |
| | B) | granite. |
| | C) | gabbro. |
| | D) | diorite. |
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12 | |
Bowen’s Reaction Series illustrates relations between:
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| | A) | temperature, pressure, and viscosity. |
| | B) | viscosity, temperature, silica content, and volatile content. |
| | C) | temperature, chemical composition, and mineral structure. |
| | D) | temperature, viscosity, and mineral composition. |
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13 | |
The two important criteria used for igneous rock classification are:
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| | A) | texture and mineral composition. |
| | B) | temperature and viscosity. |
| | C) | mineral composition and temperature. |
| | D) | texture and temperature. |
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14 | |
Basalt and gabbro:
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| | A) | formed from magma with the same silica content. |
| | B) | formed from magma with the same temperature. |
| | C) | have the same minerals. |
| | D) | all of these |
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15 | |
A rock with mineral crystals too small to be seen and low temperature minerals is:
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| | A) | granite. |
| | B) | andesite. |
| | C) | rhyolite. |
| | D) | gabbro. |
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16 | |
Igneous rocks that form entirely beneath Earth's surface are said to be:
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| | A) | platonic. |
| | B) | plutonic |
| | C) | extrusive. |
| | D) | volcanic. |
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17 | |
Andesite was named for a rock type commonly found:
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| | A) | in Mayberry, North Carolina. |
| | B) | in the Andes Mountains. |
| | C) | in Hawaii. |
| | D) | in the Rocky Mountains. |
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18 | |
Igneous processes are those which relate to:
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| | A) | solidification of magma. |
| | B) | formation of magma. |
| | C) | melting of rocks. |
| | D) | all of these |
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19 | |
The geothermal gradient of the asthenosphere is:
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| | A) | always changing as a result of plate tectonics. |
| | B) | the reverse of the geothermal gradient in the lithosphere. |
| | C) | about 1 degree per kilometer. |
| | D) | the same as the temperature structure of the lithosphere. |
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20 | |
Volcanic rocks are also:
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| | A) | Explosive. |
| | B) | Extrusive. |
| | C) | Plutonic. |
| | D) | Intrusive. |
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