WorksheetsContinental Drift
Total questions: 19
Worksheet time: 10mins
What is Pangea?
The largest ice sheet that covers the Earth
The highest mountain on Earth
A supercontinent made of the present-day continents formed 300 million years ago
Occurs at mid-ocean ridges
What evidence suggests that continents were once joined?
the topography of the seafloor
the volcanoes at mid-ocean ridges
the puzzle-like fit of coastlines
large ice sheets in Russia
Who proposed the Theory of Continental Drift?
Herry Hess
Alfred Wegner
Bill Nye
Stephen Hawking
What are three evidence used by Alfred Wegner to support his hypothesis of Continental Drift?
Climate - cold climate evidnce in hot continents.
Fossil - fossils of same animal were found in South America and Africa.
Rock formations - identical rock formations found in N.A. and Europe
Volcanoes - volcanoes all around the globe erupted at the same time
Magnetic Field - He saw how a compass behaves with alternating magnetic field signals
What is the 'Seafloor Spreading' theory?
States that the Earth was formed 4.6 billion years ago
proposes that the oceanic crust is rigid and stable
proposes that all continents were once together in a supercontinent called pangea
new oceanic crust is forming at mid-ocean ridges, pushing old crust.
What is normal polarity?
When magnets point NORTH to the Earth's magnetic field
When magnets point south to the Earth's magnetic field
takes place when Earth's magnetic field changes
place where new oceanic crust forms
What is reversed polarity?
process that forms new oceanic crust and moves it
when oceanic crust is destroyed
when magnets point SOUTH to Earth's magnetic field
A large ice sheet
Who proposed the "Seafloor Spreading Theory"?
Herry Hess
Alfred Wegner
Albert Einstein
Neil Degrasse Tyson
What takes place when Earth's magnetic field changes direction
Normal Polarity
Reversed Polarity
Magnetic Reversal
Glacial Groove
Glacial grooves in rocks in Africa suggest that this continent was once located in a much colder place
True
False
Wegner proposed that the continental drift hypothesis was not possible because the continents are NOT in constant motion
True
False
What is the theory of continental drift?
The continents move slowly over Earth's surface.
The continents moved millions of years ago, but now are fixed.
The continents were fixed, but recently have begun to move
the continents are fixed in position.
Which of the following is evidence that supports Seafloor spreading?
The presence of penguins at the equator and Antartica
Magnetic signals of minerals in rocks of the oceanic crust
temperature and age of rocks in the oceanic crust
The presence of volcanic rock in Antartica
Why were some scientists skeptical of the theory of continental drift?
They found evidence of colder climates on continents that are warm today
They did not know what caused similar rock formations on different continents
They did not know what forces caused the continents to move
They found fossils of similar organisms on several continents
What happens as the seafloor spreads apart?
The older crust folds into the mid-ocean ridge
The newer oceanic crust is pushed under the mid-ocean ridge
The older oceanic crust moves away from the mid-ocean ridge
The newer oceanic crust moves toward the mid-ocean ridge
What is the term for the state in which magnetized objects will orient themselves to point north?
magnetic field
magnetic reversal
normal polarity
reversed polarity
What confirms that the process of seafloor spreading is occuring?
Sediment closest to the mid-ocean ridge is older than the sediment farther away.
There are parallel magnetic stripes of similar composition on either side of the mid-ocean ridge
More heat leaves Earth from the abyssal plains than from the mid-ocean ridge
Sediment closer to the mid-ocean ridge is thicker than sediment farther away
What permanently records the direction of Earth's magnetic field?
basalt
sediment
magnesium
echosounder
Why do continents move?
because of centrifugal force from Earth's rotation
because the continents push through the mantle
because of the gravitational force that creates tides
because the seafloor spreads along the mid-ocean ridge
