Chapter 12 Slides

Question 1

Three major layers

Answer 1

crust, mantle, core

Question 2

Gravity and Layered Planets

Answer 2

dense iron sinks to the center

Question 3

mineral phase change

Answer 3

lower mantle rocks undergo this as the minerals are compressed under higher pressures

Question 4

P waves

Answer 4

compressional seismic

Fastest

Question 5

S waves

Answer 5

shear seismic

cannot travel through liquid

Question 6

Seismic Waves

Answer 6

P and S waves
travel fastest in stiff (rigid) rocks
velocities vary based on composition of the rocks
interactions between seismic waves and Earth;s layers
reflect and refract as they pass through the different layers of Earth

Question 7

Crust

Answer 7

composed of basalt ad gabbro (ocean)

continental crust thicker than ocean

Question 8

Moho

Answer 8

boundary between the crust and the mantle

P waves increase abruptly increase at the Moho and refract as they cross

Question 9

Mantle

Answer 9

over 82 percent of Earth is the mantle
layer between the crust and the core
solid rocky layer

Question 10

Upper Mantle

Answer 10

made of peridotite, iron, magnesium, rich rock
lithospheric mantle is the uppermost art of the mantle and extends down to 200 kilometers
asthenosphere weak layer beneath the lithospheric mantle
lowest portion of the upper mantle is the transition zone

Question 11

lower mantle

Answer 11

extends from the transition zone to the liquid core
largest layer
56% percent of Earth’s volume

Question 12

D” layer of the mantle

Answer 12

boundary between the rocky lower mantle and the liquid outer core
Cool regions thought to be the remnants of subducted lithospheric plates
Hot regions through to be start of deep mantle plumes

Question 13

outer core

Answer 13

liquid

absence of S waves

Question 14

core

Answer 14

accounts for 1/6 of Earth’s volumes

Question 15

inner core

Answer 15

solid, dense sphere
growing as earth cools
rotates faster than the crust and mantle

Question 16

Conduction and Convection

Answer 16

occur within Earth’s interior

Question 17

Radiation

Answer 17

transports heat away from Earth’s surface to space

Question 18

convection

Answer 18

transfer of heat where hot materials replace cold material

outer core

Question 19

viscosity

Answer 19

material;s resistance to flow

Question 20

conduction

Answer 20

transfer of heat through a material flow of electrons
not efficient
inner core

Question 21

geothermal gradient

Answer 21

profile of earth’s temperature at each depth

Question 22

seismic tomography

Answer 22

involves collecting data at many different seismic station

Question 23

geodynamo

Answer 23

magnetic field caused by spiraling columns of rising fluid in the outer core

Question 24

magnetic field measured

Answer 24

by declination and inclination

Question 25

declination measures

Answer 25

direction of magnetic north pole with respect to the geographic north pole

Question 26

inclination

Answer 26

downward tilt of the magnetic lines