Chapter 4.1

Front 1

asthenosphere

Back 1

zone of mantle beneath the lithosphere that consists of slowly
flowing solid rock (72)

Front 2

continental crust

Back 2

material that makes up landmasses (72)

Front 3

continental drift

Back 3

hypothesis stating that the continents once formed a single
landmass, broke up, and drifted to their present locations (67) Alfered Wegener-1912

Front 4

convection

Back 4

transfer of heat through the movement of heated material (74)

Front 5

convection current

Back 5

movement in a fluid caused by uneven heating (74) jeat rises cool sinks

Front 6

convergent boundary

Back 6

border formed by the collision of two lithospheric
plates (73)

Front 7

divergent boundary

Back 7

boundary formed by two lithospheric plates that are
moving apart (73)

Front 8

island arc

Back 8

chain of volcanic islands formed along an ocean trench (74)

Front 9

lithosphere

Back 9

thin outer shell of the Earth consisting of the crust and the rigid
upper mantle (72)

Front 10

Mid-Atlantic Ridge

Back 10

undersea mountain range with a steep, narrow valley
along its center (68)

Front 11

asthenosphere

Back 11

zone of mantle beneath the lithosphere that consists of slowly
flowing solid rock (72)

Front 12

continental crust

Back 12

material that makes up landmasses (72)

Front 13

continental drift

Back 13

hypothesis stating that the continents once formed a single
landmass, broke up, and drifted to their present locations (67)

Front 14

convection

Back 14

transfer of heat through the movement of heated material (74)

Front 15

convection current

Back 15

movement in a fluid caused by uneven heating (74)

Front 16

asthenosphere

Back 16

zone of mantle beneath the lithosphere that consists of slowly
flowing solid rock (72)

Front 17

continental crust

Back 17

material that makes up landmasses (72)

Front 18

continental drift

Back 18

hypothesis stating that the continents once formed a single
landmass, broke up, and drifted to their present locations (67)

Front 19

convection

Back 19

transfer of heat through the movement of heated material (74)

Front 20

convection current

Back 20

movement in a fluid caused by uneven heating (74)

Front 21

convergent boundary

Back 21

border formed by the collision of two lithospheric
plates (73)

Front 22

divergent boundary

Back 22

boundary formed by two lithospheric plates that are
moving apart (73)

Front 23

island arc

Back 23

chain of volcanic islands formed along an ocean trench (74)

Front 24

lithosphere

Back 24

thin outer shell of the Earth consisting of the crust and the rigid
upper mantle (72)

Front 25

Mid-Atlantic Ridge

Back 25

undersea mountain range with a steep, narrow valley
along its center (68)

Front 26

mid-ocean ridges

Back 26

system of undersea mountain ranges that wind around the
Earth (68)

Front 27

ocean trench

Back 27

deep valley in the ocean floor that forms along a subduction
zone (73)

Front 28

oceanic crust

Back 28

material that makes up the ocean floor (72)

Front 29

Pangaea

Back 29

single landmass thought to have been the origin of all continents (67)

Front 30

Panthalassa

Back 30

giant ocean surrounding Pangaea (67)

Front 31

plate tectonics

Back 31

heory that the lithosphere is made up of plates that float on the
asthenosphere and that the plates possibly are moved by convection
currents (72)

Front 32

rift valley steep

Back 32

steep, narrow valley formed as lithospheric plates separate (73)

Front 33

seafloor spreading

Back 33

movement of the ocean floor away from either side of a
mid-ocean ridge (70)

Front 34

subduction zone

Back 34

region where one lithospheric plate moves under
another (73)

Front 35

terrane

Back 35

piece of land with a geologic history distinct from that of the
surrounding land (76)

Front 36

theory of microplate

Back 36

heory that continents are a patchwork of pieces
of land that have individual geologic histories (76)

Front 37

transform boundary

Back 37

boundary formed where two lithospheric plates slide past
each other (74)

Front 38

mid-ocean ridges

Back 38

system of undersea mountain ranges that wind around the
Earth (68)

Front 39

ocean trench

Back 39

deep valley in the ocean floor that forms along a subduction
zone (73)

Front 40

oceanic crust

Back 40

material that makes up the ocean floor (72)

Front 41

Pangaea

Back 41

single landmass thought to have been the origin of all continents (67)

Front 42

Panthalassa

Back 42

giant ocean surrounding Pangaea (67)

Front 43

plate tectonics

Back 43

heory that the lithosphere is made up of plates that float on the
asthenosphere and that the plates possibly are moved by convection
currents (72)

Front 44

rift valley steep

Back 44

steep, narrow valley formed as lithospheric plates separate (73)

Front 45

seafloor spreading

Back 45

movement of the ocean floor away from either side of a
mid-ocean ridge (70)

Front 46

subduction zone

Back 46

region where one lithospheric plate moves under
another (73)

Front 47

terrane

Back 47

piece of land with a geologic history distinct from that of the
surrounding land (76)

Front 48

theory of microplate terranes

Back 48

theory of microplate terranes theory that continents are a patchwork of pieces
of land that have individual geologic histories (76)

Front 49

transform boundary

Back 49

boundary formed where two lithospheric plates slide past
each other (74