Earth's oceanic crust is ______ than continental crust.

• thinner and less dense
• thicker and denser
• thicker but less dense
• thinner but denser

Which of the following is NOT a source of heat in Earth's Core that drives convection in the Mantle.

• The Sun
• Radioactive Decay
• Leftover heat from the Earth’s formation  

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

• sinking
• subduction
• surrealism
• surrendering

What type of plate boundary?

• converging
• diverging
• transform

What feature is shown here?

• mid-ocean ridge
• trench
• earthquake
• subduction zone

What type of plate boundary?

• Converging
• Diverging
• Transform

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

• ocean trench
• river
• wasted space
• rift valley

What type of plate boundary does this picture show?

• Converging
• Diverging
• Transform

Both mid-ocean ridges and rift valleys always form at which type of boundary?

• Converging
• Diverging
• Transform

True/False: Volcanic islands form at Ocean-Ocean convergent boundaries

• True
• False