Volcanoes

What is an area on the Earth's crust where continents move together(Converge) or apart (Diverge) and magma can come through to the surface of the Earth? 

• Earthquake
• Fault
• Volcano
• Mid-Ocean Ridge

A  line of volcanic activity that surrounds the Pacific Ocean basin is the 

• Ring of Fire
• Aleutian Islands
• Hawaiian Islands
• Caribbean Islands

Which of the following factors helps determine whether a volcanic eruption will be violent or relatively quiet?

• amt of dissolved gases
• temp of magma
• composition of magma
• all of the above

Which type of volcano has the widest base?

• Cinder
• Composite
• Shield

The hot ash, gas and rock that races down the side of a volcano is known as ___

• Tephra
• Pyroclasitic flow
• Lava Dome
• Lava Plateau

If a volcano's magma is high in silicia, the volcano will probably

• erupt quietly
• remain dormant
• erupt explosively
• produce dark color lava

Pahoehoe is 

• cooler, slower moving lava
• fast moving lava
• volcanic ash 
• lava with a rough, chunky surface

Tall, cone-shaped mountains in which layers of lava alternate with layers of ash are called

• shield volcanoes
• cinder cone volcanoes
• composite volcanoes
• lava plateaus

Because Mercury and Mars are smaller than Earth and their cores have cooled, scientists think that

• the volcanic activtiy on these planets has just begun
• the volcanic activity on these planets has ended
• there never was volcanic activity on these planets
• the volcanoes on these planets are smaller and cooler than those on Earth

Before lava reaches the surface it is called

• rock
• magma
• volcanic ash
• liquid fire