Vocab
name for the supercontinent or single landmass
Pangaea
If subduction occurs faster than oceanic crust can be created, an ocean will expand.
False - Shrink
What technology was used in the mid 1900s to map the mid ocean ridge?
Sonar
The lithosphere is is broken into sections called_________, which float on top of the asthenosphere.
plates
The hypothesis of ___________ was that all continents once were joined as a single supercontinent and have since drifted apart.
continental drift
any trace of an ancient organism that has been preserved in rock
fossil
Oceanic crust near the mid-ocean ridge is younger than oceanic crust father away from the ridge
true
What is a convergent boundary? (I also need "key" word)
when two plates are pushed into each other (collide)
What is a divergent boundary?
two plates moving away from one another (divide)
What is a transform boundary?
two plates are sliding past one another (slide)
What is continental drift?
Wegener's idea that continents slowly moved over Earth's surface
Alfred Wegener provided evidence from landforms, fossils, and climate in support of his theory of the shrinking Earth
False - continental drift
What was Wegener's Hypothesis?
all continents were once joined together in a single landmass and have since drifted apart
What is a rift-valley?
Where pieces of Earth's crust diverge on the land, a deep valley occurs
When continental plates pull apart at a divergent boundary on land, a __________ forms
rift-valley
This terms refers to adding more crust to the ocean floor while older strips of rock move outward from either side of the ridge
sea-floor spreading
Mid-ocean ridges from the longest mountain ranges on Earth.
True
A collision between two pieces of continental crust as a converging boundary produces a
mountain range
Most geologists think movement of the plates is caused by what?
Convection currents in the mantle
deep-ocean trench
What is a mid-ocean ridge?
long chains of mountains that rise up from the ocean floor
Along a divergent boundary, two plates slip past each other, moving in opposite directions
false - transform boundary
In sea-floor spreading, molten material rises from the mantle and erupts.....
along mid-ocean ridges
the geological theory that states that pieces of Earth's lithosphere are in constant, slow motion is the theory of ______________
plate tectonics
The process of ______________________ continually adds new crust to the ocean floor along both sides of the mid-ocean ridge.
sea-floor spreading