Volcanoes: Nature's Explosive Landforms

Volcanoes are explosive landforms that eject molten rock and ash, primarily at plate boundaries. Magma rises through Earth's crust, leading to eruptions. Volcanoes have a magma chamber, main and secondary vents, and a crater. Eruptions can cause mudflows and destruction but also contribute to Earth's atmosphere and carbon cycle. Volcanoes can be active, dormant, or extinct.

What primarily causes volcanic eruptions?

• The formation of new rock

• The cooling of magma

• The collapse of a crater

• The movement of tectonic plates

What is the term for magma that reaches the Earth's surface?

• Lava

• Ash

• Vent

• Crater

What is the main function of a volcano's main vent?

• To store magma

• To allow magma to escape

• To create a crater

• To form new rock

What is the name of the underground collection of magma beneath a volcano?

• Main vent

• Crater

• Secondary vent

• Magma chamber

What is formed when volcanic ash and mud mix with rainwater?

• New rock formations

• Mudflows

• Volcanic craters

• Lava flows

How did volcanoes contribute to the formation of Earth's first atmosphere?

• By releasing oxygen

• By spewing water vapor and gases

• By cooling the planet

• By creating new land

What can happen to a volcano after long periods of inactivity?

• It releases more lava

• It forms new craters

• It becomes dormant or extinct

• It becomes more explosive

Which gases are released by volcanic eruptions that contribute to the carbon cycle?

• Methane and argon

• Nitrogen and helium

• Carbon dioxide and sulfur dioxide

• Oxygen and hydrogen