Volcanic Activity Quiz

Forms from lava that contains relatively small amounts of gases and silica.

• Composite volcano
• Cinder-cone volcano
• Shield volcano

Pressure decreases with depth below Earth’s surface.

• True
• False

Most of the world’s volcanoes form along ________________ plate boundaries.

• Convergent
• Divergent
• Subduction
• Plateau

Forms when a tephra are ejected into the air then fall back to Earth and pile up around a    vent.

• Composite volcano
• Cinder-cone volcano
• Shield volcano

Has broad, gently sloping sides and a nearly circular base.

• Composite volcano
• Cinder-cone volcano
• Shield volcano

Rock fragments thrown into the air during a volcanic eruption are called

• Sills
• Tephra
• Calderas
• Dikes

Small volcano with steep sides.

• Composite volcano
• Cinder-cone volcano
• Shield volcano

Most of the volcanoes that form along _______________ boundaries are located    underwater along ocean ridges.

• Convergent
• Divergent
• Subduction
• Plateau

When magma reaches Earth’s surface, it is called

• Calderas
• Vent
• Pyroclastic flow
• Lava

Rhyolitic magma forms deep beneath ______________ crust.

• Extrusive
• Intrusive
• Continental
• Oceanic