Chapter4 Section1 Plat Tectonics- Continental Drift

Front 1

continental drift

Back 1

the hypothesis that states the continents had moved

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Pangaea

Back 2

meaning "all lands"

Front 3

Panthalassa

Back 3

meaning " all seas"

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Mesosaurus

Back 4

a small extinct land reptile that lived in 270 million years ago

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Mid- Atlantic Ridge

Back 5

an undersea mountain range with a steep narrow valley running down its center

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mid-ocean ridges

Back 6

part of an entire system that vwinds their way around earth

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seafloor spreading

Back 7

as the ocean floor moved away from the ridge, it was replaced by rising magma that cooled and solidified into new rock.

Front 8

plate tectonics theory

Back 8

the theory that describes the contiental movement and a possible explanation of how the continents moved

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tectonics

Back 9

comes from the greek word "construction"

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oceanic crust

Back 10

forms from the material on the ocean floor

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continental crust

Back 11

material that makes up the landmass

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lithosphere

Back 12

thin outer shell of the earth consisting of the crust and the rigid upper mantle

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asthenosphere

Back 13

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

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divergent boundary

Back 14

boundary formed by two lithospheric plates that are moving apart

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rift valley

Back 15

steep, narrow valley formed as lithospheric plates separate

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convergent boundary

Back 16

border formed by the direct collision of two lithospheric plates

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subduction zone

Back 17

region where one lithospheric plate moves under another

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ocean trench

Back 18

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

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isalnd arc

Back 19

chain of volcanic islands formed along an ocean trench

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transform fault boundary

Back 20

boundary formed where two lithospheric plates slide past each other

Front 21

convergent boundary

Back 21

border formed by the direct collision of two lithospheric plates

Front 22

subduction zone

Back 22

region where one lithospheric plate moves under another

Front 23

ocean trench

Back 23

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

Front 24

isalnd arc

Back 24

chain of volcanic islands formed along an ocean trench

Front 25

transform fault boundary

Back 25

boundary formed where two lithospheric plates slide past each other

Front 26

convection

Back 26

the transfer of heat through the movement of a fluid material

Front 27

convection currents

Back 27

movment ina fluid caused by uneven heating

Front 28

theory of suspect terranes

Back 28

the theory that the continents are a patchwork of pieces of land that have individual geological history

Front 29

terrane

Back 29

a piece of land with a geological history distinct from that of the surrounding land