Volcanoes form when magma from beneath the Earth's surface is forced up through openings in the crust called vents. They occur at plate boundaries where tectonic plates are moving together or apart, as well as at hot spots where areas of the mantle are unusually hot and melt rock that rises toward the surface. Common examples of active volcanoes include Kilauea volcano in Hawaii and volcanoes in Iceland, Mexico, Ecuador, Indonesia, and Costa Rica.

1. Introduction to Volcanoes!MEXICOECUADOR8SCIENCE Mon. April 11PASTOINDONESIACOSTA RICA

2. What is a volcano?A volcano is an opening in the Earth’s surfaceMost volcanoes are dormant Not currently active Active volcanoesHawaii: Kilauea volcanoIceland: “the land of fire and ice”

3. How is a volcano formed?Inside the earth heat and pressure causes rock to melt and turn to magma Magma is forced up to the surface of the Earth because it is less dense flows out through an opening called a vent The lava cools quickly to form layers

4. Where do volcanoes occur?Directly related to the movement of the Earth’s plates along plate boundariesOccur where plates are moving together or apartCalled hot spotsPlates moving apart: Mid-Atlantic ridge separates and forms long cracks

5. Plates moving together: North and South American plates are being forced under the Caribbean plates Hot SpotsHot spots: Hawaiian islands are volcanic islands but are not found on the edge of the plates