WBHS Rupe Plate Tectonics 1

Which idea did Alfred Wegener propose in 1915?

• Continental Drift

• Plate Tectonics

• Sea-floor Spreading

Alfred Wegener's hypothesis was not readily accepted because

• it seemed impossible

• the geologist did not want to believe a meteorologist

• it had already been discovered previously

• he could not explain the mechanism capable of moving a continent

The presence of mesosaurus fossils in S. America and Africa is evidence of continental drift because (Pick 2)

• the fossils were found all over the globe back then.

• the fossils are found in areas that match up when the continents are moved back to their positions in Pangaea.

• it could not possibly have swam across the Atlantic Ocean.

• the fossils are hard to find

The puzzle like fit of the continents is evidence of continental drift. What other types of evidence are there? (Pick all that apply)

• Fossil Evidence

• Climate Evidence

• Astronomical Evidence

• Rock Types and Mountain Ranges

Which sea-floor feature creates a rift valley as the ocean crust forms and spreads apart?

• Continental Rise

• Deep Ocean Trench

• Abyssal Plain

• Mid-Ocean Ridge

Which sea-floor feature is created as oceanic crust is subducted down towards the mantle?

• Deep Ocean Trench

• Seamount

• Continental Shelf

• Mid-Ocean Ridge

Which three answers are evidence of sea-floor spreading?

• Rock Age - younger at mid-ocean ridge and older near continents

• Paleomagnetic signatures are symmetric across the ridges.

• Earthquakes mark the edges of the tectonic plates.

• The sea-floor is older than the continental crust.

The sea-floor spreading process begins when

• ocean plate is subducted under a continent

• magma begins to rise to the surface underneath the mid-ocean ridge

• new crust forms in the rift valley of the mid-ocean ridge.

• the magnetic field flips polarity

According to your notes, the ring of fire is marked by the locations of..... (Pick 2)

• desert plateaus

• earthquakes

• vertical cliffs

• volcanoes

Since new ocean crust forms as lava cools, it must be

• sedimentary rock

• intrusive igneous rock

• extrusive igneous rock

• metamorphic rock