Download Unit 7 Vocabulary

Unit 7 Vocabulary
1. Pangaea - a supercontinent that incorporated almost
all the landmasses on Earth. *Use your book to draw
a picture of Pangaea.
2. theory of plate tectonics - the theory that Earth's
outer layer is made up of plates, which have moved
throughout Earth's history.
3. continental drift - a theory proposed by Alfred
Wegener in 1912 that explained how continents shift
position on Earth's surface.
4. sea floor spreading - a process that occurs at midocean ridges, where new oceanic crust is formed
through volcanic activity and then gradually moves
away from the ridge.
5. convection currents – currents carrying heat from
the interior of the earth to the surface
6. subsidence - the motion of the Earth's surface as it
shifts downward
7. boundary - the border between two tectonic plates
8. convergent boundary – a tectonic boundary where
two plates are moving toward each other. *draw a
diagram to show this
9. divergent boundary - a tectonic boundary where two
plates are moving away from each other and new
crust is forming from magma that rises to the Earth's
surface between the two plates. *draw a diagram to
show this
10.
transform boundary – a tectonic boundary
where the two plates slide against each other in a
sideways motion *draw a diagram to show this
11.
rift – an area in the middle of the continental
plate where the plate is beginning to separate. A large
valley will form in the area as the crust thins.
12.
ridge – regions of earthquake activity where two
plates come together
13.
trench – a deep depression of the sea floor
caused by thee subduction of one plate under another
14.
fault - a break in the rocks that make up the
Earth’s crust, along which rocks on either side have
moved past each other.
15.
subduction zone - a collision between two of
Earth's tectonic plates, where one plate sinks into the
mantle underneath the other plate.