What were 2 kinds of evidence were used to prove that the seafloor spread?

• rock formations, WWII shipwrecks

• magnetic seafloor stripes, WWII ship logs

• magnetic seafloor stripes, age of rocks

The ocean floor sinks below a deep-ocean trench and back into the mantle in a process known as

• sinking
• subduction
• surrealism
• surrendering

When continental plates pull apart at a divergent boundary on land, a(an) _____ forms.

• ocean trench
• river
• wasted space
• rift valley

What does the theory of continental drift state?

• The continents were once joined in a super-continent and have moved over time
• Continents are stationary and do not move
• The Earth is broken into lithospheric plates that move due to convection currents
• none of the above

Alfred Wegener used all of the following for evidence of his idea EXCEPT...

• The shapes of the continents fitting together like a puzzle

• Similar fossils on different continents

• Comparable modern weather patterns on different continents

• Similar rock formations on different continents

According to the continental drift hypothesis, the presence of similar fossils in South America and Africa supports which scientific idea?

• Animals easily and frequently travel from Africa to South America.

• Species of animals probably traveled between continents on natural rafts (such as trees destroyed in tsunamis).

• Land bridges once existed that connected the continents.

• South America and Africa were once connected together.

What geologic feature/event would you most likely to find at a convergent boundary between two pieces of continental crust?

• Volcano
• Mountain
• Rift
• Island Arc

A mid-ocean RIDGE is located at the boundary of two tectonic plates. Which diagram correctly models the relative plate motion on each side of a mid ocean ridge?

• 
• 
• 
• 

Most geologists think the movement of Earth’s plates is caused by _______ .

• convection, ridge push and slab pull

• continental drift, seafloor spreading and volcanoes

• convergent, divergent and transform boundaries

• conduction, convection and radiation

Why does an oceanic plate subduct under a continental plate?

• because oceanic crust is thicker than continental crust
• because oceanic crust is heavier than continental crust
• because oceanic crust is younger than continental crust
• because oceanic crust is more dense than continental crust