How a Volcano Erupts 1 Rock melts deep beneath Earth’s surface, or crust. 2 Pressure forces the heated rock through cracks in the crust. 3 The melted rock, or lava, erupts from the volcano.

How a Volcano Erupts

  • 1 Rock melts deep beneath Earth’s surface, or crust.

  • 2 Pressure forces the heated rock through cracks in the crust.

  • 3 The melted rock, or lava, erupts from the volcano.

Key Vocabulary

  • erupt v., to break open or shoot out suddenly

Before You Move On

  • 1. Explain What dangers do scientists face when they study volcanoes?

  • 2. Cause and Effect What happens to make a volcano erupt?