chapter 2 Flashcards
melted iron and nickel; 1,800 miles below surface
outer core
solid; nickel and iron; 4,000 miles below the surface
inner core
hot rock; silicon, oxygen, aluminum, iron magnesium
mantle
3 to 30 miles deep; plates float on upper mantle
crust
the theory that the continents were once joined and slowly ripped apart
continental drift
one super-continent that existed millions of years ago
Pangea
internal forces cause the earth’s plates to move about ___ inches a year
4
when one plate collides with another and the heavier plate slides under the lighter plate
subduction
bends in layers of rock
folds
breaks in the earth’s surface
faults
____ often occur where different plates meet each other
earthquakes
where most earthquakes and volcanoes occur
ring of fire
mountains formed when lava rises through the earth’s crust
volcanoes
tidal wave caused by underwater earthquakes
tsunamis
process that breaks rocks into pieces
weathering
water dissolves some chemicals in rocks causing them to crumble
chemical weathering
water seeps into cracks of rocks, it freezes and expands, forcing it apart
physical weathering
moves dust, sand, and soil; results in sand dunes
wind erosion
flowing water cuts into the land; results in valleys and canyons
water erosion
land is changed as large bodies of ice move across it, creating lakes and valleys
glacier erosion
ice that covers large areas (ice caps)
sheet glaciers
when fallen snow in mountain builds up and turns to ice
mountain glacier
regular movement of water from the ocean to air to ground and back to the ocean
water cycle
suns heat causes vapor from oceans to rise to form clouds
evaporation
when warm air cools and water vapor turns to liquid water
condensation
