Earth's Structure and Composition

Earth's surface is part of the:

• asthenosphere
• lithosphere
• stratosphere
• troposphere

The most common element found in Earth's crust is:

• oxygen
• hydrogen
• aluminum
• iron

The Earth is approximately

• 3 million years old
• 50 million years old
• 2 billion years old
• 4.5 billion years old

Which of the following layers contains most of the Earth's mass?

• the core
• the mantle
• the oceanic crust
• the continental crust

How did the Himalayan Mountains form?

• erosion
• convection
• glacial movements
• colliding tectonic plates

The largest unit of time is the:

• era
• period
• stage
• eon

About 3/4 of Earth's volcanoes and about _________ of earthquakes occur around the Ring of Fire.

• 5%
• 10%
• 50%
• 90%

The San Andreas Fault in California occurs at a:

• convergent boundary
• divergent boundary
• transform boundary
• subduction 

The creation of new ocean floor would result from which type of plate boundary?

• transform
• convergent
• divergent
• fault

The largest mass extinction on Earth occurred at the end of the:

• Mesozoic Era
• Permian Period
• Carboniferous Period
• Cretaceous Period