Science Chapter 5 Sudy Guide
continental drift
Wegner's idea that the continents began to slowly moved over Earth's surface became known as...
Pangea
What is the name of the supercontinent said to exist 225 million years ago?
states that earth's plates are in slow, constant motion, driven by convection currents in the mantle
What is the theory of plate tectonics?
That all the continents were once one large landmass
What was Werner's hypothesis about the continents?
Wegener could not name the force that pushed and pulled the continents
Why did geologists not accept Wegener's theory?
fossil
any trace of an ancient organism that has been preserved in rock
faults
break in earth's crust where rocks have slipped past each other- form along these boundaries
no
can crust be created or destroyed at transform boundaries
plates to move
convection currents in earth's mantle cause...
the collision squeezes the crust into high mountain ranges
describe what happens when 2 plates carrying continental crust collide
The denser plate subducts below the other at deep ocean trench
describe what happens when 2 plates carrying oceanic crust collide
The denser oceanic plate subducts below the continental plate
describe what happens when a plate carrying a oceanic crust collides with a plate carrying continental crust
plates
earth's lithosphere is broken into pieces separated by cracks. these pieces are called...
plate tectonics
interaction of the earths rigid ;lithosphere plates as they slide slowly the asthosphere
mid-ocean ridges, where new crust is added during sea-floor spreading
most divergent boundaries occur along
convection currents in the mantle
plate tectonics are driven by...
convergent boundary
plates come together, or converge, at a...
divergent boundary
plates move apart, or diverge from each other at a...,
transform boundary
plates slip past each other along a...
subduction
the process by which the ocean floor sinks beneath a deep-ocean trench and back into the mantle again
sea-floor spreading
the process of mid-ocean ridges continually adding more crust and old rock moving outward from the mid ocean ridge
the size and shape of the oceans
the processes of subduction and seafloor spreading can change...
volcanoes, mountains, earthquakes, and islands
what do convergent boundaries form?
crust is created here
what do divergent boundaries do to the crust?
rift zones, mid-ocean ridges, sea floor spreading
what do divergent boundaries form?
great changes in earths's surface and on the ocean floor. this also includes the formation of volcanoes, mountain ranges, and deep-ocean trenches
what do movements in plate boundaries cause?
the crust is neither created or destroyed here
what do transform boundaries do to the crust?
earthquakes
what do transform boundaries form?
it destroys the crust
what does convergent boundaries do to crust?
the formation, movement, and subduction of earth's plates
what does plate tectonics explain?
Rift Valley
where pieces of earth's crust diverge on land, a deep valley called a ___________________ forms
Continent
A single landmass is called a...
Farther away the rock was from the ridge, the older it was
How does evidence from drilling samples support mid-ocean ridges?
They line up with Earth's magnetc poles
How does evidence from magnetic strips support sea-floor spreading?
Pillow rocks, wich form only when molten material hardens quickly after erupting under water.
How does evidence from ocean floor material support sea-floor spreading?
deep-ocean trenches
-Places where the ocean floor plunges into deep underwater canyons
mid-ocean ridges
-Seams formed mountain ranges that ran along the middle of some ocean floors -form long chains of mountains that rise up from the ocean floor
sonar
-a device that uses sound waves to measure the distance to an object -used to map mid-ocean ridges
fossils from warm or cool climates may be found in the opposite climate area
How did evidence from climate support Werner's Pangea theory?
Fossils have been found in landmasses separated by oceans
How did evidence from fossils support Wegner's Pangea theory? ex: (Glossopteris)
Some landmasses, such as mountains, line up in separate continents
How did evidence from land features support Wegener's Pangea theory?
