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20 Cards in this Set

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  • Back
Continental drift
hypothesis stating that the continnents once formed a single landmass, broke up, and drifted to their present locations. (Contending that all of the present day continents were connected side-by- side, as long ago as the carboniferous 300 million years)
single landmass thought to have been the oringin of all contunents
giant ocean surrounding Panagea
a small extinct land reptile that lived 270 million years ago
Mid-Atlantic ridges
undersea mountain range with a steep, narrow valley along its center
Mid-Ocean ridges
system of undersea mountain ranges that wind around the Earth
Seafloor spreading
movement of the ocean floor away from either side of a mid-ocean ridge
Plate tectonics
theory that the lithosphere is made up of plates that float on the asthenosphere and that the plates possibly are moved by convectioncurrents
Oceanic crust
material that makes up the ocean floor
Continental crust
material that makes up landmass
thin outer shell of the Earth consisting of the crust and the ridged upper mantle
zone of mantle beneth the lithosphere that consists of slowly flowing solid rock
is the study of formation of features in the Earth's crust
divergent boundaries
boundary formed by two lithospheric plates that are moving apart
rift valley
steep, narrow valley formed as a lithosphiric plates sperate
convergent boundary
border formed by direct collision of two lithospheric plates
subduction zone
region where one lithospheric plate moves under another
ocean trench
deep valley in the ocean floor that forms along a subduction zone
island arc
chain of volvanic lisland formed along an ocean trench
transform fault boundary
boundary formed where 2 lithospheric plates alides past each other