Chapter 3 Landforms Flashcards
Two processes that sculpt earth
Internal and External
Internal processes
movement of the entire continents (slow moving, hundreds of millions of years)
External processes
Weathering, erosion, and deposition (change the look/shape of landform over time)
what is the difference between magma and lava?
magma - melted rock below the surface of the crust
lava - magma that spills onto the surface of the earth
what does magma harden into? lava?
magma - basalt
lava - granite
the order of the layers of the earth (from the farthest down)
asthenosphere > lithosphere > crust (continental and oceanic)
Difference between continental and oceanic
continental - continents, granite, thicker and less dense, does not subduct
oceanic - oceans, basalt (volcanic), thinner, more dense, subducts
Which type of crust forms the newest rock?
oceanic
What is responsible for the movement of plates?
Asthenospheric convection
The ____ of solid rock allows ____ from hot mantle and and interior
plasticity, convection
convection is the movement of the
asthenosphere
movement of the asthenosphere results in movement of
the plates above
the asthenosphere allows for the movement of the ________
lithosphere
solid rock supporting earth’s crust and containing tectonic plates
lithosphere
the outermost layer of the lithosphere that sits on the moving plates and has landforms is called the
crust
lithosphere is fractured into how many primary plates?
seven (and several minor)
where lithospheric plates meet is known as the
plate boundary
what two things are plate interactions responsible for
landform creation and tectonic hazards
three plate boundary types
divergent, convergent, transform
when two plates move apart it is known as
divergent
when two plates move toward each other
convergent
where one plate slips laterally past another
transform
two types of divergent boundaries
continental rift and mid-ocean ridge (oceanic rift)
what is created at mid-ocean ridges?
new oceanic lithosphere
at mid ocean ridges is ____ rock
youngest
oldest rock is found (closer/further) from oceanic rift/mid ocean ridges
further
what is seafloor spreading
the process where new oceanic crust is formed at the ridge, spreads out, and pushes older crust away from the ridge
continental rift will form a ____ , which will eventually form a _____, and then a _____
rift valley (african rift valley), new ocean basin (red sea), mature ocean (atlantic)
what are among the largest bodies of freshwater in the world?
rift valley lake
true or false: lake victoria is a rift lake
false, is not
lake baikal is caused from what?
continental rift
what is the deepest lake in the world?
lake baikal
how old is lake baikal
25 million years old
the red sea began as what?
rift valley
what has continued the rift of the red sea?
sea floor spreading
the rift valley of the red sea which led into seafloor spreading (oceanic rift) will eventually create what?
a new ocean basin
continental crust > new ____ > ____ form > new _____
rift valley, volcanoes, ocean basin
what is exposed in iceland?
the mid-atlantic ridge
iceland is split by what?
divergent plate boundary
three types of convergent boundary types
oceanic-oceanic (subduction)
oceanic-continental (subduction)
continental-continental (collision)
what landforms are a result of subduction?
volcanoes, volcanic islands, mountains, ocean trenches
what landforms are a result of collison?
tallest terrestrial mountains and plateaus
the himalayan range is a result from what type of plate movement?
convergent collision
the process of mountain building occurring from the collision, compression, and deformation of the earth’s crust when tectonic plates converge is called
orogeny
the process by which oceanic lithosphere of one plate bends and dives into the mantle beneath another plate
subduction
in oceanic-oceanic or oceanic/continental the ____ plate subducts
densest
subduction “____” earth’s crust
recycles
why won’t two continental plates form volcanic arcs?
because collision occurs not subduction (thus mountains are made not volcanoes)
compare and contrast a continental arc and island arc
both are from convergent subduction and both result in volcanic arcs
continental arc forms when oceanic lithosphere subducts below continental lithosphere
island arc forms when a more dense oceanic lithosphere subducts beneath a less dense oceanic lithosphere
what is the andes an example of? (what type of plate movement)
convergent subduction (continental island arc which means continent and ocean subduction)
islands of japan and aleutian islands in the bering sea are examples of what?
ocean island arc (oceanic-oceanic convergent subduction)
what natural disaster does transform plate boundary result in? why?
earthquakes; pressure release
where are transform plate boundary most common?
seafloor mid ocean ridges (rarely on dry land)
true or false: transform plate boundary results in dramatic landforms
false: does not
what is the san andreas fault an example of?
transform plate boundary
is a hot spot formed from plate interaction?
no
hotspots of ____ burst through ___ at fixed ____
magma, lithosphere, spots
because of hot spots, what is made when the magma cools?
new land
the hawaiian islands are created from a ______ ______
magma plume
the hawaiian islands moves with which plate?
pacific
iceland: mid atlantic ridge exposed, divergent plate boundary, and a ____ _____
hotspot plume
