Layers, Pangaea, Continental Drift

​Two Column Note Reminder

​Red words go on the left of the page.

Yellow information goes on the right of the page next to the term/volcabulary word associated with the information.

​Alfred Wegener

• Created the theory in 1912 about continental drift

• The supercontinent was named Pangea

• Wegener could not prove the theory so It was initially rejected.

​Harry Hess

• In 1960s created theories surrounding seafloor spreading

• New ocean basins form from volcanos

• Ocean floor forms in between pieces that have split​

Multiple Choice

Wegener's idea of Continental Drift was rejected by geologists because _________.

• He used too many pieces of evidence to support the idea.

• He couldn't identify why or how the continents to moved around.

• He wanted to know what Earth looked like millions of years ago, which is impossible.

• They were afraid of the new idea.

Multiple Choice

What theory states that the continents were once part of a super continent called Pangaea and have moved slowly to their current locations over hundreds of millions of years.

• Oceanic wandering

• Land-form Evidence

• Continental Drift

• Fossil Distribution

Multiple Choice

Who is the person credited with developing the theory of continental drift?

• Harry Hess

• Albert Einstein

• Alfred Wegener

• Isaac Newton

Multiple Choice

What is Pangaea?

• Supercontinent

• The landmass consisting of North America & South America

• The scientist who discovered continental drift

• How the continents have drifted apart

Multiple Choice

What was Pangea?

• An ancient Mountain Range that divided Africa

• A large valley where civilization began.

• A supercontinent where all Earth's land masses were joined.

• A large meteor that hit Earth and destroyed all of the dinosaurs

​Continental Drift & Pangea

​Continental Drift

Proposed the hypothesis that the continents were once joined together in a single large land mass called Pangea and eventually split a part due to plate tectonic movements.

​Pangea

• Former supercontinent formed 200 million years ago. Northern Portion named Gondwana and the Southern Portion Laurasia.

• Broke a part about 70 million years ago.

​This Process does not stop. The continents are still slowly moving and it has been confirmed through satellite images that the Atlantic Ocean has been growing yearly.

​Evidence for Continental Drift

• Continents fit together like a puzzle.

• The best fit includes the continentals shelves (the continental edges under water).

• The best fit would be the Atlantic Coastlines of Africa and South America.

• Fossils of Plants and animals of the same species found on vastly different continents.

• Rock strata in South America, Africa, India, Antartica, and Australia show similarities.

• Wegener showed that the same three layers occur in each continent and are separated by oceans and were created during Pangea creation.

Multiple Choice

How does fossil evidence support Wegener's hypothesis of continental drift?

• Similar fossils are found along continental margins that appear to join together.

• Fossils are found in areas where the present-day climate could not have supported the organisms that made the fossils.

• Similar fossils of giant, land-dwelling dinosaurs are found on continents separated by oceans.

• all of the above

Multiple Select

What items were found in Antarctica that lead us to believe the climate was once much warmer? (Select 3)

• Plant fossils of tropical ferns

• Animal fossils of reptiles that live in warm conditions

• Coal deposits that formed in tropical swamps

• Mammoth fossils preserved in ice

Multiple Choice

Wegener found fossils of ancient ferns on Antarctica, this shows

• That some ferns can survive temperatures well below freezing

• That humans put ferns on Antarctica millions of years ago

• -That Antarctica drifted from a warmer climate where plants could grow

• That fossils can be formed in cold climates

Multiple Choice

The east coast of South America seems to fit into the wet coast of Africa, this evidence for Continental Drift is called...

• fit/shape of continents

• fossil evidence

• geologic evidence

• climate evidence

​Seafloor Spreading

• Theory developed by Henry Hess in the 1960s.

• Using radar, he discovered that the seafloor has both trenches and mid-ocean ridges.

• Proposed that hot, less dense material below Earth's Crust rises toward the surface at the mid-ocean ridges.

• Then, it flows sideways, carrying the seafloor away from the ridge in both directions.

• As the seafloor spreads apart at a mid-ocean ridge, new seafloor is created.

• The older seafloor moves away from the ridge in opposite directions.

• This theory has explained how the crust could move.

Multiple Choice

Process by which new ocean crust forms.

• Seafloor spreading

• Continental drift

• Mid-ocean ridge

• Rift

Multiple Choice

Undersea mountain range.

• Rift

• Mid-ocean ridge

• seafloor spreading

• Continental drift

Multiple Choice

What are Mid-Ocean Ridges?

• A chain of underwater waterfalls 

• A chain of underwater volcanos

• A chain of underwater mountains

• A chain of underwater rocks

Multiple Choice

Sea floor spreading

• creates new oceanic crust

• destroys or recycles crust

• creates new continental crust

• creates old crust