CM 4

• Volcano - A vent, hill, or mountain from which molten or hot rocks with gaseous material have been ejected.​
• Lava flow - Molten rock flowing down the sides of a volcano
• Fissure - A large crack in the earth through which lava can flow
• Crust - The upper part of the earth
• Ash and cinders - Tiny airborne pieces of rock and lava
• Bomb - A lump of lava thrown out of a volcano while still molten
• Crater - the bowl-shaped depression around the mouth of a volcano
• Central vent - A channel in the neck of a volcano where magma erupts
• Magma chamber - An underground area where thick, molten
• Lava - molten rock on the surface
• Magma - molten rock underground
• Active - Has erupted in the last 10,000 years
• Dormant - has erupted in the past, but not recently
• Extinct - are unlikely to erupt again