1. Introduction to Volcanoes! 8SCIENCE ECUADOR PASTO INDONESIA MEXICO COSTA RICA

2. What is a volcano? A volcano is an opening in the Earth’s surface Most volcanoes are dormant – Not currently active Active volcanoes – Hawaii: Kilauea volcano – Iceland: “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 boundaries Occur where tectonic plates are moving together or apart Or may be formed by a hot spot Plates moving apart: Mid- Atlantic ridge separates and forms long cracks Plates moving together: Nazca and South American plates are being forced under the Caribbean plates

5. Hot Spots Hot spots: Ex. Hawaiian islands are volcanic islands but are not found on the edge of the plates Some areas in the mantle are hotter than others These hot spots melt rock and it is forced upwards towards the crust Volcanoes are formed in a line because the Pacific plate is moving over the hot spot