Download Continental Drift and Plate Tectonics ANSWER KEY

ANSWER KEY Continental Drift and Plate Tectonics – Making Your Own Notes!
Continental Drift
1.) The “father” of the Continental Drift theory is Alfred Wegener, a German scientist who believe that the continents were
once all connected, creating one super continent called Pangaea.
2.) He published his theory in 1915.
3.) Wegener provided four examples of evidence to support this theory that the continents were “drifting”. They are:
a.
Continents fit together like a jigsaw puzzle
b.
Fossils of the same plants and animals have been found on different continents
c.
Mountain ranges separated by oceans have the same rock sequencing, type and age
d.
Glacial scars from the same ice age and ice sheets have been found on different continents
4.) What was Wegener unable to explain that left many of his scientific peers doubting his theory?
He could not explain what force was powerful enough to move entire continents
5.) What was Wegener doing when he died in the year 1930 on expedition in Greenland?
He was still doing research to find answers to help explain his theory of continental drift
Plate Tectonics
1.) The “father” of the Plate Tectonic theory is J. Tuzo Wilson, a Canadian geophysicist.
2.) This theory states that the Earth’s crustal pieces called plates are moving over hot magma in the mantle layer of the Earth.
3.) He helped to explain that the Earth’s crust is made up of these two parts:
a.
Continental Crust
and
b. Oceanic Crust
4.) The crustal plate that we live on is called the North American plate.
5.) What causes the plates to move? Convection currents.
6.) What causes magma to rise in this upper layer of the mantle? Heat from the core.
7.) What happens after it rises? It cools then sinks back towards the core where it becomes heated again. This continuous
movement is called a convection current or cycle.
8.) Convection causes the crustal plates to move like a conveyor belt in these three directions:
a.
Towards each other (convergent)
b.
Away from each other (divergent)
c.
Slide past one another (transform)
9.) Converging plates create: mountain ranges such the Himalayas in India, Nepal and Pakistan.
10.) Subducting plates create: erupting volcanic mountain ranges such as the Cascade Mountain Range on the west
coast of the USA and the Andes Mountains of South America and deep ocean trenches such as the Marianas
Trench.
11.) Diverging plates create: mid ocean ridges such as the Mid-Atlantic ridge that runs north to south
along the middle of the Atlantic Ocean between North and South America and Europe and Africa.
12.) Transform boundaries are where plates slide by one another, but because they are jagged
they often get stuck and tremendous pressure can build up. When this pressure is released, it causes
the plates to break apart suddenly creating an earthquake, such as what commonly occurs along
the San Andreas fault line in California.
13.) The Plate Tectonic Theory, contributed to by J. Tuzo Wilson, has been instrumental in our current
understanding of the geologic forces that constantly shape and re-shape our planet.