* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Volcanoes form as molten rock erupts.
Mount Meager massif wikipedia , lookup
Large igneous province wikipedia , lookup
Mount Garibaldi wikipedia , lookup
Level Mountain wikipedia , lookup
Llullaillaco wikipedia , lookup
Mount Pleasant Caldera wikipedia , lookup
Mount Edziza volcanic complex wikipedia , lookup
Cerro Blanco (volcano) wikipedia , lookup
Lascar (volcano) wikipedia , lookup
Volcanology of Io wikipedia , lookup
Mount St. Helens wikipedia , lookup
Mount Pinatubo wikipedia , lookup
Cascade Volcanoes wikipedia , lookup
Olympus Mons wikipedia , lookup
Silverthrone Caldera wikipedia , lookup
Cerro Azul (Chile volcano) wikipedia , lookup
Shield volcano wikipedia , lookup
Mount Vesuvius wikipedia , lookup
Mount Pelée wikipedia , lookup
Nevado del Ruiz wikipedia , lookup
KEY CONCEPT Volcanoes form as molten rock erupts. STANDARDS 8–3.7 Illustrate the creation and changing of landforms that have occurred through geologic processes (including volcanic eruptions and mountain-building forces). BEFORE, you learned NOW, you will learn • Magma is molten rock inside Earth • Magma forms as a plate sinking in a subduction zone starts to melt • Volcanoes can form over hot spots far from plate boundaries • Where most volcanoes are located • How volcanoes erupt • What types of volcanoes there are EXPLORE Eruptions What happens when a volcano erupts? PROCEDURE 1 VOCABULARY Add water to an empty film canister until it is three-fourths full. 2 Drop an antacid tablet in the water and put volcano p. 262 lava p. 263 pyroclastic flow p. 264 the lid on the canister. Observe what happens. MATERIALS • empty film canister • effervescent antacid tablet • water WHAT DO YOU THINK? • What happened to the water and to the canister lid? • What caused the changes you observed? • How might the events you observed be similar to the eruption of a volcano? Volcanoes erupt many types of material. VOCABULARY Make a word triangle for volcano in your notebook. Earth’s thin outer layer is made of cool rock, but most of Earth is made of extremely hot rock and molten metal. Some of the heat inside Earth escapes to the surface through volcanoes. A volcano is an opening in Earth’s crust through which molten rock, rock fragments, and hot gases erupt. A mountain built up from erupted material is also called a volcano. A volcano may erupt violently or gently. A violent eruption can cause tremendous destruction even if not much molten rock reaches the surface. For example, a volcano might throw out huge amounts of rock fragments that start fires where they land or fall in thick layers on roofs, causing them to collapse. A volcano can erupt gently yet pour out rivers of molten rock that flow long distances. The violence of an eruption depends mainly on the type of magma feeding the volcano. 262 Unit 2: The Changing Earth