Introduction (Chapter 1)

Question 1

True or False: Is melt the same as magma?

Answer 1

False. Melt is apart of the magma (Diagram 1)

Question 2

Why are igneous processes most dominant in contributing to a differentiated planet?

Answer 2

They are responsible for the division of the crust from the mantle.

Question 3

What are the two main silicate groups of Earth’s mantle? (think elements)

Answer 3

Mg and Fe minerals

Question 4

What 3 common minerals can be found in Earth’s mantle?

Answer 4

Olivine, Orthopyroxene, and Clinopyroxene

Question 5

True or False: The asthenosphere is completely solid.

Answer 5

False. The asthenosphere isn’t completely solid. It is unstable and ductile.

Question 6

Name the 3 major units of Earth’s interior.

Answer 6

The crust, mantle, and core

Question 7

What kind of rocks make-up the majority of oceanic crust?

Answer 7

Basaltic Rocks

Question 8

What kind of rocks make-up the upper level of the continental crust?

Answer 8

Felsic rocks (granodioritic)

Question 9

What kind of rocks make-up the lower level of the continental crust?

Answer 9

Same as oceanic crust (basaltic rocks)

Question 10

What makes up Earth’s core?

Answer 10

Fe-rich metallic alloys with minor S, Si, Ni, O

Question 11

Pressure _____ with depth

Answer 11

Increases

Question 12

Temperature ______ with depth

Answer 12

Increases

Question 13

Thermal gradient ______ with depth

Answer 13

Varies

Question 14

Thermal gradient in oceanic lithosphere is ______ than that in the continental lithosphere

Answer 14

Higher

Question 15

What is an adiabatic geotherm?

Answer 15

It is the steepening of the geothermal profile in the asthenosphere due to convection. (Diagram 2)

Question 16

The melting of rocks depends on what three components?

Answer 16

Temperature, Pressure, and Composition

Question 17

What are the three mechanisms that lead to melting?

Answer 17

1) Increasing temperature (Adiabatic upwelling)
2) Decreasing pressure (Adiabatic upwelling)
3) Lowering solidus (addition of fluids)

Question 18

What is the solidus?

Answer 18

Start melting

Question 19

What is the liquidus?

Answer 19

Complete melting

Question 20

True or False: Global distribution of heat flow is directly related to plate tectonics.

Answer 20

True

Question 21

Plate tectonics are driven by what?

Answer 21

Convectional cells

Question 22

What are the three mechanisms of magma generation?

Answer 22

1) Mid-ocean ridge basalts
2) Ocean island basalts
3) Island arc basalts
(Diagram 3)